Scholars@Duke
David R. McClay Jr.

David R. McClay Jr.

Arthur S. Pearse Distinguished Professor of Biology
Biology
dmcclay@duke.edu
Box 90338, Department of Biology, Durham, NC 27708-1000
4102 French Science Center, Science Dr., Durham, NC 27708
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Selected Publications

Feedback circuits are numerous in embryonic gene regulatory networks and offer a stabilizing influence on evolution of those networks.

Journal Article EvoDevo · June 2023 The developmental gene regulatory networks (dGRNs) of two sea urchin species, Lytechinus variegatus (Lv) and Strongylocentrotus purpuratus (Sp), have remained remarkably similar despite about 50 million years since a common ancestor. Hundreds of parallel e ... Full text Open Access Cite

Wound repair in sea urchin larvae involves pigment cells and blastocoelar cells.

Journal Article Developmental biology · November 2022 Sea urchin larvae spend weeks to months feeding on plankton prior to metamorphosis. When handled in the laboratory they are easily injured, suggesting that in the plankton they are injured with some frequency. Fortunately, larval wounds are repaired throug ... Full text Cite

Development of a larval nervous system in the sea urchin.

Chapter · January 2022 This review reports recent findings on the specification and patterning of neurons that establish the larval nervous system of the sea urchin embryo. Neurons originate in three regions of the embryo. Perturbation analyses enabled construction of gene regul ... Full text Cite

Foreword

Book · January 1, 2022 Cite

Reprint of: Conditional specification of endomesoderm.

Journal Article Cells & development · December 2021 Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simul ... Full text Cite

Author Correction: Guidelines and definitions for research on epithelial-mesenchymal transition.

Journal Article Nature reviews. Molecular cell biology · December 2021 Full text Cite

Developmental single-cell transcriptomics in the Lytechinus variegatus sea urchin embryo.

Journal Article Development (Cambridge, England) · October 2021 Using scRNA-seq coupled with computational approaches, we studied transcriptional changes in cell states of sea urchin embryos during development to the larval stage. Eighteen closely spaced time points were taken during the first 24 h of development of Ly ... Full text Open Access Cite

Conditional specification of endomesoderm.

Journal Article Cells & development · September 2021 Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simul ... Full text Cite

Methodologies for Following EMT In Vivo at Single Cell Resolution.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2021 An epithelial-mesenchymal transition (EMT) occurs in almost every metazoan embryo at the time mesoderm begins to differentiate. Several embryos have a long record as models for studying an EMT given that a known population of cells enters the EMT at a know ... Full text Cite

Perspective on Epithelial-Mesenchymal Transitions in Embryos.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2021 The epithelial-mesenchymal transition (EMT) is a key process required for building the early body plan of metazoa. It involves coordinated and precisely timed changes in multiple cell processes such as de-adhesion, motility, invasion, and cell polarity. Wh ... Full text Cite

Chromosomal-Level Genome Assembly of the Sea Urchin Lytechinus variegatus Substantially Improves Functional Genomic Analyses.

Journal Article Genome biology and evolution · July 2020 Lytechinus variegatus is a camarodont sea urchin found widely throughout the western Atlantic Ocean in a variety of shallow-water marine habitats. Its distribution, abundance, and amenability to developmental perturbation make it a popular model for ecolog ... Full text Cite

Guidelines and definitions for research on epithelial-mesenchymal transition.

Journal Article Nature reviews. Molecular cell biology · June 2020 Epithelial-mesenchymal transition (EMT) encompasses dynamic changes in cellular organization from epithelial to mesenchymal phenotypes, which leads to functional changes in cell migration and invasion. EMT occurs in a diverse range of physiological and pat ... Full text Cite

Developmental origin of peripheral ciliary band neurons in the sea urchin embryo.

Journal Article Developmental biology · March 2020 In the sea urchin larva, most neurons lie within an ectodermal region called the ciliary band. Our understanding of the mechanisms of specification and patterning of these peripheral ciliary band neurons is incomplete. Here, we first examine the gene regul ... Full text Cite

Gastrulation in the sea urchin.

Chapter · January 2020 Gastrulation is arguably the most important evolutionary innovation in the animal kingdom. This process provides the basic embryonic architecture, an inner layer separated from an outer layer, from which all animal forms arise. An extraordinarily simple an ... Full text Cite

Developmental Single-cell transcriptomics in theLytechinus variegatusSea Urchin Embryo

Journal Article · 2020 Featured Publication Here we employed scRNA-seq coupled with computational approaches to examine molecular changes in cells during specification and differentiation. We examined the first 24 hours of development of the sea urchin Lytechinus variegatus ( Lv ) with 18 time point ... Full text Open Access Cite

Methods for transplantation of sea urchin blastomeres.

Journal Article Methods in cell biology · January 2019 The stereotypic cleavage pattern of sea urchin embryos provides a platform for dissection of early lineage decisions that lead to cell diversification. Cell transplantation provides a useful tool for understanding those decisions. The methods described in ... Full text Cite

Spatial and temporal patterns of gene expression during neurogenesis in the sea urchin Lytechinus variegatus.

Journal Article EvoDevo · January 2019 BackgroundThe sea urchin is a basal deuterostome that is more closely related to vertebrates than many organisms traditionally used to study neurogenesis. This phylogenetic position means that the sea urchin can provide insights into the evolution ... Full text Cite

Unlocking mechanisms of development through advances in tools.

Chapter · January 2019 This perspective describes how our understanding of sea urchin development has been enabled by advances in technology. The early conceptual discoveries that put the sea urchin embryo on the research map had to wait until technologies were available to expl ... Full text Cite

Feedback circuits are numerous in embryonic gene regulatory networks and offer a stabilizing influence on evolution of those networks.

Journal Article EvoDevo · June 2023 The developmental gene regulatory networks (dGRNs) of two sea urchin species, Lytechinus variegatus (Lv) and Strongylocentrotus purpuratus (Sp), have remained remarkably similar despite about 50 million years since a common ancestor. Hundreds of parallel e ... Full text Open Access Cite

Wound repair in sea urchin larvae involves pigment cells and blastocoelar cells.

Journal Article Developmental biology · November 2022 Sea urchin larvae spend weeks to months feeding on plankton prior to metamorphosis. When handled in the laboratory they are easily injured, suggesting that in the plankton they are injured with some frequency. Fortunately, larval wounds are repaired throug ... Full text Cite

Development of a larval nervous system in the sea urchin.

Chapter · January 2022 This review reports recent findings on the specification and patterning of neurons that establish the larval nervous system of the sea urchin embryo. Neurons originate in three regions of the embryo. Perturbation analyses enabled construction of gene regul ... Full text Cite

Foreword

Book · January 1, 2022 Cite

Reprint of: Conditional specification of endomesoderm.

Journal Article Cells & development · December 2021 Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simul ... Full text Cite

Author Correction: Guidelines and definitions for research on epithelial-mesenchymal transition.

Journal Article Nature reviews. Molecular cell biology · December 2021 Full text Cite

Developmental single-cell transcriptomics in the Lytechinus variegatus sea urchin embryo.

Journal Article Development (Cambridge, England) · October 2021 Using scRNA-seq coupled with computational approaches, we studied transcriptional changes in cell states of sea urchin embryos during development to the larval stage. Eighteen closely spaced time points were taken during the first 24 h of development of Ly ... Full text Open Access Cite

Conditional specification of endomesoderm.

Journal Article Cells & development · September 2021 Early in animal development many cells are conditionally specified based on observations that those cells can be directed toward alternate fates. The endomesoderm is so named because early specification produces cells that often have been observed to simul ... Full text Cite

Methodologies for Following EMT In Vivo at Single Cell Resolution.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2021 An epithelial-mesenchymal transition (EMT) occurs in almost every metazoan embryo at the time mesoderm begins to differentiate. Several embryos have a long record as models for studying an EMT given that a known population of cells enters the EMT at a know ... Full text Cite

Perspective on Epithelial-Mesenchymal Transitions in Embryos.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2021 The epithelial-mesenchymal transition (EMT) is a key process required for building the early body plan of metazoa. It involves coordinated and precisely timed changes in multiple cell processes such as de-adhesion, motility, invasion, and cell polarity. Wh ... Full text Cite

Chromosomal-Level Genome Assembly of the Sea Urchin Lytechinus variegatus Substantially Improves Functional Genomic Analyses.

Journal Article Genome biology and evolution · July 2020 Lytechinus variegatus is a camarodont sea urchin found widely throughout the western Atlantic Ocean in a variety of shallow-water marine habitats. Its distribution, abundance, and amenability to developmental perturbation make it a popular model for ecolog ... Full text Cite

Guidelines and definitions for research on epithelial-mesenchymal transition.

Journal Article Nature reviews. Molecular cell biology · June 2020 Epithelial-mesenchymal transition (EMT) encompasses dynamic changes in cellular organization from epithelial to mesenchymal phenotypes, which leads to functional changes in cell migration and invasion. EMT occurs in a diverse range of physiological and pat ... Full text Cite

Developmental origin of peripheral ciliary band neurons in the sea urchin embryo.

Journal Article Developmental biology · March 2020 In the sea urchin larva, most neurons lie within an ectodermal region called the ciliary band. Our understanding of the mechanisms of specification and patterning of these peripheral ciliary band neurons is incomplete. Here, we first examine the gene regul ... Full text Cite

Gastrulation in the sea urchin.

Chapter · January 2020 Gastrulation is arguably the most important evolutionary innovation in the animal kingdom. This process provides the basic embryonic architecture, an inner layer separated from an outer layer, from which all animal forms arise. An extraordinarily simple an ... Full text Cite

Developmental Single-cell transcriptomics in theLytechinus variegatusSea Urchin Embryo

Journal Article · 2020 Featured Publication Here we employed scRNA-seq coupled with computational approaches to examine molecular changes in cells during specification and differentiation. We examined the first 24 hours of development of the sea urchin Lytechinus variegatus ( Lv ) with 18 time point ... Full text Open Access Cite

Methods for transplantation of sea urchin blastomeres.

Journal Article Methods in cell biology · January 2019 The stereotypic cleavage pattern of sea urchin embryos provides a platform for dissection of early lineage decisions that lead to cell diversification. Cell transplantation provides a useful tool for understanding those decisions. The methods described in ... Full text Cite

Spatial and temporal patterns of gene expression during neurogenesis in the sea urchin Lytechinus variegatus.

Journal Article EvoDevo · January 2019 BackgroundThe sea urchin is a basal deuterostome that is more closely related to vertebrates than many organisms traditionally used to study neurogenesis. This phylogenetic position means that the sea urchin can provide insights into the evolution ... Full text Cite

Unlocking mechanisms of development through advances in tools.

Chapter · January 2019 This perspective describes how our understanding of sea urchin development has been enabled by advances in technology. The early conceptual discoveries that put the sea urchin embryo on the research map had to wait until technologies were available to expl ... Full text Cite

Neurogenesis in the sea urchin embryo is initiated uniquely in three domains.

Journal Article Development (Cambridge, England) · November 2018 Many marine larvae begin feeding within a day of fertilization, thus requiring rapid development of a nervous system to coordinate feeding activities. Here, we examine the patterning and specification of early neurogenesis in sea urchin embryos. Lineage an ... Full text Cite

Identification of neural transcription factors required for the differentiation of three neuronal subtypes in the sea urchin embryo.

Journal Article Developmental biology · March 2018 Correct patterning of the nervous system is essential for an organism's survival and complex behavior. Embryologists have used the sea urchin as a model for decades, but our understanding of sea urchin nervous system patterning is incomplete. Previous hist ... Full text Cite

New insights from a high-resolution look at gastrulation in the sea urchin, Lytechinus variegatus.

Journal Article Mechanisms of development · December 2017 BackgroundGastrulation is a complex orchestration of movements by cells that are specified early in development. Until now, classical convergent extension was considered to be the main contributor to sea urchin archenteron extension, and the relat ... Full text Cite

Reprint of: In Memoriam - Eric H. Davidson (1937-2015)

Journal Article Developmental Biology · April 15, 2016 Full text Cite

Contribution of hedgehog signaling to the establishment of left-right asymmetry in the sea urchin.

Journal Article Developmental biology · March 2016 Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing thi ... Full text Cite

Comparative Developmental Transcriptomics Reveals Rewiring of a Highly Conserved Gene Regulatory Network during a Major Life History Switch in the Sea Urchin Genus Heliocidaris.

Journal Article PLoS biology · March 2016 The ecologically significant shift in developmental strategy from planktotrophic (feeding) to lecithotrophic (nonfeeding) development in the sea urchin genus Heliocidaris is one of the most comprehensively studied life history transitions in any animal. Al ... Full text Cite

Sea Urchin Morphogenesis.

Journal Article Current topics in developmental biology · January 2016 In the sea urchin morphogenesis follows extensive molecular specification. The specification controls the many morphogenetic events and these, in turn, precede patterning steps that establish the larval body plan. To understand how the embryo is built it w ... Full text Cite

Developmental gene regulatory networks in sea urchins and what we can learn from them.

Journal Article F1000Research · January 2016 Sea urchin embryos begin zygotic transcription shortly after the egg is fertilized.  Throughout the cleavage stages a series of transcription factors are activated and, along with signaling through a number of pathways, at least 15 different cell types are ... Full text Cite

Eric H. Davidson (1937–2015).

Journal Article Developmental biology · October 2015 Full text Cite

Deployment of a retinal determination gene network drives directed cell migration in the sea urchin embryo.

Journal Article eLife · September 2015 Gene regulatory networks (GRNs) provide a systems-level orchestration of an organism's genome encoded anatomy. As biological networks are revealed, they continue to answer many questions including knowledge of how GRNs control morphogenetic movements and h ... Full text Cite

Specification to biomineralization: following a single cell type as it constructs a skeleton.

Journal Article Integrative and comparative biology · October 2014 The sea urchin larva is shaped by a calcite endoskeleton. That skeleton is built by 64 primary mesenchyme cells (PMCs) in Lytechinus variegatus. The PMCs originate as micromeres due to an unequal fourth cleavage in the embryo. Micromeres are specified in a ... Full text Cite

Delayed transition to new cell fates during cellular reprogramming.

Journal Article Developmental biology · July 2014 In many embryos specification toward one cell fate can be diverted to a different cell fate through a reprogramming process. Understanding how that process works will reveal insights into the developmental regulatory logic that emerged from evolution. In t ... Full text Cite

Sub-circuits of a gene regulatory network control a developmental epithelial-mesenchymal transition.

Journal Article Development (Cambridge, England) · April 2014 Epithelial-mesenchymal transition (EMT) is a fundamental cell state change that transforms epithelial to mesenchymal cells during embryonic development, adult tissue repair and cancer metastasis. EMT includes a complex series of intermediate cell state cha ... Full text Cite

Branching out: origins of the sea urchin larval skeleton in development and evolution.

Journal Article Genesis (New York, N.Y. : 2000) · March 2014 It is a challenge to understand how the information encoded in DNA is used to build a three-dimensional structure. To explore how this works the assembly of a relatively simple skeleton has been examined at multiple control levels. The skeleton of the sea ... Full text Cite

Editorial-sea urchin special issue.

Journal Article Genesis (New York, N.Y. : 2000) · March 2014 Full text Cite

Perturbations to the hedgehog pathway in sea urchin embryos.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2014 The Hedgehog pathway has been shown to be an important developmental signaling pathway in many organisms (Ingham and McMahon. Genes Dev 15:3059-3087, 2001). Recently that work has been extended to developing echinoderm embryos (Walton et al. Dev Biol 331(1 ... Full text Cite

Ectodermal inputs into patterning skeletogenesis

Conference INTEGRATIVE AND COMPARATIVE BIOLOGY · January 1, 2014 Link to item Cite

Left-right asymmetry in the Sea Urchin

Journal Article Genesis · January 1, 2014 Summary: The sea urchin is a penta-radial marine invertebrate of the phylum Echinodermata, yet sea urchins develop initially as bilaterally symmetric embryos and become penta-radial secondarily during development of the adult. Late in embryogenesis indirec ... Full text Cite

Hedgehog signaling requires motile cilia in the sea urchin.

Journal Article Molecular biology and evolution · January 2014 A relatively small number of signaling pathways govern the early patterning processes of metazoan development. The architectural changes over time to these signaling pathways offer unique insights into their evolution. In the case of Hedgehog (Hh) signalin ... Full text Cite

Short-range Wnt5 signaling initiates specification of sea urchin posterior ectoderm.

Journal Article Development (Cambridge, England) · December 2013 The border between the posterior ectoderm and the endoderm is a location where two germ layers meet and establish an enduring relationship that also later serves, in deuterostomes, as the anatomical site of the anus. In the sea urchin, a prototypic deutero ... Full text Cite

Left-right asymmetry in the sea urchin embryo: BMP and the asymmetrical origins of the adult.

Journal Article PLoS biology · January 2012 Bilateral animals, including humans and most metazoans, are not perfectly symmetrical. Some internal structures are distributed asymmetrically to the right or left side. A conserved Nodal and BMP signaling system directs molecular pathways that impart the ... Full text Cite

Morphogenesis in sea urchin embryos: linking cellular events to gene regulatory states.

Journal Article Wires Dev Biol · 2012 Gastrulation in the sea urchin begins with ingression of the primary mesenchyme cells (PMCs) at the vegetal pole of the embryo. After entering the blastocoel the PMCsmigrate, form a syncitium, and synthesize the skeleton of the embryo. Several hours after ... Full text Cite

Evolutionary crossroads in developmental biology: sea urchins.

Journal Article Development (Cambridge, England) · July 2011 Embryos of the echinoderms, especially those of sea urchins and sea stars, have been studied as model organisms for over 100 years. The simplicity of their early development, and the ease of experimentally perturbing this development, provides an excellent ... Full text Cite

The control of foxN2/3 expression in sea urchin embryos and its function in the skeletogenic gene regulatory network.

Journal Article Development (Cambridge, England) · March 2011 Early development requires well-organized temporal and spatial regulation of transcription factors that are assembled into gene regulatory networks (GRNs). In the sea urchin, an endomesoderm GRN model explains much of the specification in the endoderm and ... Full text Cite

Cleavage and Gastrulation in the Sea Urchin.

Journal Article Encyclopedia of Life Sciences. · 2011 Cite

Dynamics of Delta/Notch signaling on endomesoderm segregation in the sea urchin embryo.

Journal Article Development (Cambridge, England) · January 2010 Endomesoderm is the common progenitor of endoderm and mesoderm early in the development of many animals. In the sea urchin embryo, the Delta/Notch pathway is necessary for the diversification of this tissue, as are two early transcription factors, Gcm and ... Full text Open Access Cite

Roles of Dsh in the regulation of sea urchin gastrulation.

Journal Article Dev Dyn · December 2009 Cite

Hedgehog signaling patterns mesoderm in the sea urchin.

Journal Article Developmental biology · July 2009 The Hedgehog (Hh) signaling pathway is essential for patterning many structures in vertebrates including the nervous system, chordamesoderm, limb and endodermal organs. In the sea urchin, a basal deuterostome, Hh signaling is shown to participate in organi ... Full text Cite

Blocking Dishevelled signaling in the noncanonical Wnt pathway in sea urchins disrupts endoderm formation and spiculogenesis, but not secondary mesoderm formation.

Journal Article Developmental dynamics : an official publication of the American Association of Anatomists · July 2009 Dishevelled (Dsh) is a phosphoprotein key to beta-catenin dependent (canonical) and beta-catenin independent (noncanonical) Wnt signaling. Whereas canonical Wnt signaling has been intensively studied in sea urchin development, little is known about other W ... Full text Cite

Sea urchin embryonic skeletogenesis is regulated by microRNA

Journal Article Developmental Biology · July 2009 Full text Cite

Chordin is required for neural but not axial development in sea urchin embryos.

Journal Article Developmental biology · April 2009 The oral-aboral (OA) axis in the sea urchin is specified by the TGFbeta family members Nodal and BMP2/4. Nodal promotes oral specification, whereas BMP2/4, despite being expressed in the oral territory, is required for aboral specification. This study expl ... Full text Cite

LvNumb works synergistically with Notch signaling to specify non-skeletal mesoderm cells in the sea urchin embryo.

Journal Article Development (Cambridge, England) · August 2008 Activation of the Notch signaling pathway segregates the non-skeletogenic mesoderm (NSM) from the endomesoderm during sea urchin embryo development. Subsequently, Notch signaling helps specify the four subpopulations of NSM, and influences endoderm specifi ... Full text Cite

Gene regulatory networks governing morphogenesis

Conference Developmental Biology · July 2008 Full text Cite

FGF signals guide migration of mesenchymal cells, control skeletal morphogenesis [corrected] and regulate gastrulation during sea urchin development.

Journal Article Development (Cambridge, England) · January 2008 The sea urchin embryo is emerging as an attractive model to study morphogenetic processes such as directed migration of mesenchyme cells and cell sheet invagination, but surprisingly, few of the genes regulating these processes have yet been characterized. ... Full text Cite

Evolution of the Wnt pathways.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2008 Wnt proteins mediate the transduction of at least three major signaling pathways that play central roles in many early and late developmental decisions. They control diverse cellular behaviors, such as cell fate decisions, proliferation, and migration, and ... Full text Cite

Secondary axis specification in sea urchin embryos

Journal Article Signal Transduction · May 14, 2007 Secondary axis specification is a process that relies on asymmetric nuclearization of transcription factors in flies and vertebrates, such that the crucial factor is nuclear and therefore functional only in cells along one side of the embryo. In vertebrate ... Full text Cite

The Snail repressor is required for PMC ingression in the sea urchin embryo.

Journal Article Development (Cambridge, England) · March 2007 In metazoans, the epithelial-mesenchymal transition (EMT) is a crucial process for placing the mesoderm beneath the ectoderm. Primary mesenchyme cells (PMCs) at the vegetal pole of the sea urchin embryo ingress into the floor of the blastocoele from the bl ... Full text Cite

Protein tyrosine and serine-threonine phosphatases in the sea urchin, Strongylocentrotus purpuratus: identification and potential functions.

Journal Article Developmental biology · December 2006 Protein phosphatases, in coordination with protein kinases, play crucial roles in regulation of signaling pathways. To identify protein tyrosine phosphatases (PTPs) and serine-threonine (ser-thr) phosphatases in the Strongylocentrotus purpuratus genome, 17 ... Full text Cite

RTK and TGF-beta signaling pathways genes in the sea urchin genome.

Journal Article Developmental biology · December 2006 The Receptor Tyrosine kinase (RTK) and TGF-beta signaling pathways play essential roles during development in many organisms and regulate a plethora of cellular responses. From the genome sequence of Strongylocentrotus purpuratus, we have made an inventory ... Full text Cite

A genome-wide survey of the evolutionarily conserved Wnt pathways in the sea urchin Strongylocentrotus purpuratus.

Journal Article Developmental biology · December 2006 The Wnt pathways are evolutionarily well-conserved signal transduction pathways that are known to play important roles in all Metazoans investigated to date. Here, we examine the Wnt pathway genes and target genes present in the genome of the echinoderm St ... Full text Cite

Genomics and expression profiles of the Hedgehog and Notch signaling pathways in sea urchin development.

Journal Article Developmental biology · December 2006 The Hedgehog (Hh) and Notch signal transduction pathways control a variety of developmental processes including cell fate choice, differentiation, proliferation, patterning and boundary formation. Because many components of these pathways are conserved, it ... Full text Cite

The sea urchin kinome: a first look.

Journal Article Developmental biology · December 2006 This paper reports a preliminary in silico analysis of the sea urchin kinome. The predicted protein kinases in the sea urchin genome were identified, annotated and classified, according to both function and kinase domain taxonomy. The results show that the ... Full text Cite

Lineage-specific expansions provide genomic complexity among sea urchin GTPases.

Journal Article Developmental biology · December 2006 In every organism, GTP-binding proteins control many aspects of cell signaling. Here, we examine in silico several GTPase families from the Strongylocentrotus purpuratus genome: the monomeric Ras superfamily, the heterotrimeric G proteins, the dynamin supe ... Full text Cite

The genomic underpinnings of apoptosis in Strongylocentrotus purpuratus.

Journal Article Developmental biology · December 2006 Programmed cell death through apoptosis is a pan-metazoan character involving intermolecular signaling networks that have undergone substantial lineage-specific evolution. A survey of apoptosis-related proteins encoded in the sea urchin genome provides ins ... Full text Cite

Repression of mesodermal fate by foxa, a key endoderm regulator of the sea urchin embryo.

Journal Article Development (Cambridge, England) · November 2006 The foxa gene is an integral component of the endoderm specification subcircuit of the endomesoderm gene regulatory network in the Strongylocentrotus purpuratus embryo. Its transcripts become confined to veg2, then veg1 endodermal territories, and, followi ... Full text Cite

The canonical Wnt pathway in embryonic axis polarity.

Journal Article Seminars in cell & developmental biology · April 2006 The canonical Wnt pathway plays crucial roles in multiple developmental processes, including in axis specification. Throughout the animal kingdom, this pathway has been reported to drive patterning of axes as different as the animal-vegetal axis in echinod ... Full text Cite

p38 MAPK in development and cancer.

Journal Article Cell cycle (Georgetown, Tex.) · April 2006 p38 is a MAPK that has been shown to induce a wide variety of biological effects in cell culture in response to a wide range of stimuli. These effects are dependent not only on the stimuli, but also on the cellular context, resulting in a bewildering array ... Full text Cite

RhoA regulates initiation of invagination, but not convergent extension, during sea urchin gastrulation.

Journal Article Developmental biology · April 2006 During gastrulation, the archenteron is formed using cell shape changes, cell rearrangements, filopodial extensions, and convergent extension movements to elongate and shape the nascent gut tube. How these events are coordinated remains unknown, although m ... Full text Cite

Frizzled5/8 is required in secondary mesenchyme cells to initiate archenteron invagination during sea urchin development.

Journal Article Development (Cambridge, England) · February 2006 Wnt signaling pathways play key roles in numerous developmental processes both in vertebrates and invertebrates. Their signals are transduced by Frizzled proteins, the cognate receptors of the Wnt ligands. This study focuses on the role of a member of the ... Full text Cite

p38 MAPK is essential for secondary axis specification and patterning in sea urchin embryos.

Journal Article Development (Cambridge, England) · January 2006 Most eggs in the animal kingdom establish a primary, animal-vegetal axis maternally, and specify the remaining two axes during development. In sea urchin embryos, the expression of Nodal on the oral (ventral) side of the embryo is the first known molecular ... Full text Cite

SNPs in the neural cell adhesion molecule 1 gene (NCAM1) may be associated with human neural tube defects.

Journal Article Hum Genet · July 2005 Neural tube defects (NTDs) are common birth defects, occurring in approximately 1/1,000 births; both genetic and environmental factors are implicated. To date, no major genetic risk factors have been identified. Throughout development, cell adhesion molecu ... Full text Link to item Cite

A Fringe-modified Notch signal affects specification of mesoderm and endoderm in the sea urchin embryo.

Journal Article Developmental biology · June 2005 Fringe proteins are O-fucose-specific beta-1,3 N-acetylglucosaminyltransferases that glycosylate the extracellular EGF repeats of Notch and enable Notch to be activated by the ligand Delta. In the sea urchin, signaling between Delta and Notch is known to b ... Full text Cite

LvGroucho and nuclear beta-catenin functionally compete for Tcf binding to influence activation of the endomesoderm gene regulatory network in the sea urchin embryo.

Journal Article Developmental biology · March 2005 In the sea urchin embryo, specification of the endomesoderm is accomplished by the activity of a network of regulatory genes in the vegetal hemisphere, called the endomesoderm gene regulatory network (GRN). The activation of this network is mediated primar ... Full text Cite

SpHnf6, a transcription factor that executes multiple functions in sea urchin embryogenesis.

Journal Article Developmental biology · September 2004 The Strongylocentrotus purpuratus hnf6 (Sphnf6) gene encodes a new member of the ONECUT family of transcription factors. The expression of hnf6 in the developing embryo is triphasic, and loss-of-function analysis shows that the Hnf6 protein is a transcript ... Full text Cite

Nuclear beta-catenin-dependent Wnt8 signaling in vegetal cells of the early sea urchin embryo regulates gastrulation and differentiation of endoderm and mesodermal cell lineages.

Journal Article Genesis (New York, N.Y. : 2000) · July 2004 The entry of beta-catenin into vegetal cell nuclei beginning at the 16-cell stage is one of the earliest known molecular asymmetries seen along the animal-vegetal axis in the sea urchin embryo. Nuclear beta-catenin activates a vegetal signaling cascade tha ... Full text Cite

PI3K inhibitors block skeletogenesis but not patterning in sea urchin embryos.

Journal Article Developmental dynamics : an official publication of the American Association of Anatomists · April 2004 Skeletogenesis in the sea urchin embryo is a simple model of biomineralization, pattern formation, and cell-cell communication during embryonic development. The calcium carbonate skeletal spicules are secreted by primary mesenchyme cells (PMCs), but the sk ... Full text Cite

Methods for embryo dissociation and analysis of cell adhesion.

Journal Article Methods in cell biology · January 2004 Full text Cite

Blastomere isolation and transplantation.

Journal Article Methods in cell biology · January 2004 Full text Cite

Spdeadringer, a sea urchin embryo gene required separately in skeletogenic and oral ectoderm gene regulatory networks.

Journal Article Developmental biology · September 2003 The Spdeadringer (Spdri) gene encodes an ARID-class transcription factor not previously known in sea urchin embryos. We show that Spdri is a key player in two separate developmental gene regulatory networks (GRNs). Spdri is expressed in a biphasic manner, ... Full text Cite

Activation of pmar1 controls specification of micromeres in the sea urchin embryo.

Journal Article Developmental biology · June 2003 pmar1 is a transcription factor in the paired class homeodomain family that was identified and found to be transcribed in micromeres beginning at the fourth cleavage of sea urchin development [Dev. Biol. 246 (2002), 209]. Based on in situ data, molecular p ... Full text Cite

Regulatory gene networks and the properties of the developmental process.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 2003 Genomic instructions for development are encoded in arrays of regulatory DNA. These specify large networks of interactions among genes producing transcription factors and signaling components. The architecture of such networks both explains and predicts de ... Full text Cite

Primary mesenchyme cell patterning during the early stages following ingression.

Journal Article Developmental biology · February 2003 Sea urchin primary mesenchyme cells (PMCs) ingress into the blastocoel during an epithelial-to-mesenchymal transition (EMT), migrate along the blastocoelar wall for a period of time, and then settle into a subequatorial ring to form the larval skeleton. Fl ... Full text Cite

A provisional regulatory gene network for specification of endomesoderm in the sea urchin embryo.

Journal Article Developmental biology · June 2002 We present the current form of a provisional DNA sequence-based regulatory gene network that explains in outline how endomesodermal specification in the sea urchin embryo is controlled. The model of the network is in a continuous process of revision and gr ... Full text Cite

A genomic regulatory network for development.

Journal Article Science (New York, N.Y.) · March 2002 Development of the body plan is controlled by large networks of regulatory genes. A gene regulatory network that controls the specification of endoderm and mesoderm in the sea urchin embryo is summarized here. The network was derived from large-scale pertu ... Full text Cite

LvNotch signaling plays a dual role in regulating the position of the ectoderm-endoderm boundary in the sea urchin embryo.

Journal Article Development (Cambridge, England) · June 2001 The molecular mechanisms guiding the positioning of the ectoderm-endoderm boundary along the animal-vegetal axis of the sea urchin embryo remain largely unknown. We report here a role for the sea urchin homolog of the Notch receptor, LvNotch, in mediating ... Full text Cite

Quantitative measurement of cell adhesion using centrifugal force.

Journal Article Current protocols in cell biology · May 2001 In order to study the biophysical forces involved in cell-substrate (or cell-cell) adhesion, it is necessary to measure the strength of adhesion. Two questions can be addressed using the centrifugal cell adhesion assay provided in this unit: what is the li ... Full text Cite

A micromere induction signal is activated by beta-catenin and acts through notch to initiate specification of secondary mesenchyme cells in the sea urchin embryo.

Journal Article Development (Cambridge, England) · December 2000 At fourth cleavage of sea urchin embryos four micromeres at the vegetal pole separate from four macromeres just above them in an unequal cleavage. The micromeres have the capacity to induce a second axis if transplanted to the animal pole and the absence o ... Full text Cite

A BMP pathway regulates cell fate allocation along the sea urchin animal-vegetal embryonic axis.

Journal Article Development (Cambridge, England) · March 2000 To examine whether a BMP signaling pathway functions in specification of cell fates in sea urchin embryos, we have cloned sea urchin BMP2/4, analyzed its expression in time and space in developing embryos and assayed the developmental consequences of chang ... Full text Cite

Specification of endoderm and mesoderm in the sea urchin.

Journal Article Zygote (Cambridge, England) · January 2000 Cite

The role of thin filopodia in motility and morphogenesis.

Journal Article Experimental cell research · December 1999 Full text Cite

LvNotch signaling mediates secondary mesenchyme specification in the sea urchin embryo.

Journal Article Development (Cambridge, England) · April 1999 Cell-cell interactions are thought to regulate the differential specification of secondary mesenchyme cells (SMCs) and endoderm in the sea urchin embryo. The molecular bases of these interactions, however, are unknown. We have previously shown that the sea ... Full text Cite

alphaSU2, an epithelial integrin that binds laminin in the sea urchin embryo.

Journal Article Developmental biology · March 1999 At gastrulation in the sea urchin embryo dramatic cell adhesion changes contribute to primary mesenchyme cell ingression movements and to cell rearrangements during archenteron invagination. At ingression, quantitative adhesion assays demonstrated previous ... Full text Cite

Nuclear beta-catenin is required to specify vegetal cell fates in the sea urchin embryo.

Journal Article Development (Cambridge, England) · January 1999 Beta-catenin is thought to mediate cell fate specification events by localizing to the nucleus where it modulates gene expression. To ask whether beta-catenin is involved in cell fate specification during sea urchin embryogenesis, we analyzed the distribut ... Full text Cite

Ectoderm cell--ECM interaction is essential for sea urchin embryo skeletogenesis.

Journal Article Developmental biology · April 1998 Paracentrotus lividus sea urchin nectin (Pl-nectin) is an extracellular matrix (ECM) protein of the sea urchin embryo on the apical surface of the ectoderm and has been shown to be an adhesive substrate for embryonic cells. A monoclonal antibody (McAb) to ... Full text Cite

Cortical granule exocytosis is triggered by different thresholds of calcium during fertilisation in sea urchin eggs.

Journal Article Zygote (Cambridge, England) · February 1998 In sea urchin eggs, fertilisation is followed by a calcium wave, cortical granule exocytosis and fertilisation envelope elevation. Both the calcium wave and cortical granule exocytosis sweep across the egg in a wave initiated at the point of sperm entry. U ... Full text Cite

A molecular analysis of hyalin--a substrate for cell adhesion in the hyaline layer of the sea urchin embryo.

Journal Article Developmental biology · January 1998 The hyaline layer of echinoderm embryos is an extraembryonic matrix that functions as a substrate for cell adhesion through early development. The major constituent of the hyaline layer is the protein hyalin, a fibrillar glycoprotein of approximately 330 k ... Full text Cite

Changes in the pattern of adherens junction-associated beta-catenin accompany morphogenesis in the sea urchin embryo.

Journal Article Developmental biology · December 1997 beta-Catenin was originally identified biochemically as a protein that binds E-cadherin in cultured cells and that interaction was later shown to be essential for cadherin function. Independently, armadillo, the beta-catenin homolog in Drosophila melanogas ... Full text Cite

Characterization of the role of cadherin in regulating cell adhesion during sea urchin development.

Journal Article Developmental biology · December 1997 During development, the modulation of cadherin adhesive function is proposed to control various morphogenetic events including epithelial-mesenchymal conversions and tubulogenesis, although the mechanisms responsible for regulating cadherin activity during ... Full text Cite

Identification and localization of a sea urchin Notch homologue: insights into vegetal plate regionalization and Notch receptor regulation.

Journal Article Development (Cambridge, England) · September 1997 The specifications of cell types and germ-layers that arise from the vegetal plate of the sea urchin embryo are thought to be regulated by cell-cell interactions, the molecular basis of which are unknown. The Notch intercellular signaling pathway mediates ... Full text Cite

Regulated exocytosis and sequential construction of the extracellular matrix surrounding the sea urchin zygote.

Journal Article Developmental biology · June 1997 After fertilization most eggs become surrounded by a complex extracellular matrix. This study examines those matrix assembly processes that are triggered by fertilization of the sea urchin egg. The study uses antibodies that identify five different storage ... Full text Cite

The allocation of early blastomeres to the ectoderm and endoderm is variable in the sea urchin embryo.

Journal Article Development (Cambridge, England) · June 1997 During sea urchin development, a tier-to-tier progression of cell signaling events is thought to segregate the early blastomeres to five different cell lineages by the 60-cell stage (E. H. Davidson, 1989, Development 105, 421-445). For example, the sixth e ... Full text Cite

NIEHS/EPA Workshops. Cellular migration.

Journal Article Reproductive toxicology (Elmsford, N.Y.) · March 1997 Full text Cite

Molecular cloning of the first metazoan beta-1,3 glucanase from eggs of the sea urchin Strongylocentrotus purpuratus.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · June 1996 We report the molecular cloning of the first beta-1,3 glucanase from animal tissue. Three peptide sequences were obtained from beta-1,3 glucanase that had been purified from eggs of the sea urchin Strongylocentrotus purpuratus and the gene was cloned by PC ... Full text Cite

Regulative capacity of the archenteron during gastrulation in the sea urchin.

Journal Article Development (Cambridge, England) · February 1996 Gastrulation in the sea urchin involves an extensive rearrangement of cells of the archenteron giving rise to secondary mesenchyme at the archenteron tip followed by the foregut, midgut and hindgut. To examine the regulative capacity of this structure, pie ... Full text Cite

Dynamics of thin filopodia during sea urchin gastrulation.

Journal Article Development (Cambridge, England) · August 1995 At gastrulation in the sea urchin embryo, a dramatic rearrangement of cells establishes the three germ layers of the organism. Experiments have revealed a number of cell interactions at this stage that transfer patterning information from cell to cell. Of ... Full text Cite

Cell adhesion and cell signaling at gastrulation in the sea urchin

Journal Article Theriogenology · January 1, 1995 The sea urchin embryo follows a relatively simple cell behavioral sequence in its gastrulation movements. The embryo reaches the gastrula stage as a spherical monolayer of cells. To form the mesoderm, primary mesenchyme cells ingress by delaminating from t ... Full text Cite

Characterization of moesin in the sea urchin Lytechinus variegatus: redistribution to the plasma membrane following fertilization is inhibited by cytochalasin B.

Journal Article Journal of cell science · January 1995 We have investigated the distribution and function of an ezrin-radixin-moesin-like (ERM) molecule in the sea urchin. A sea urchin homologue of moesin was cloned that shares 75% amino acid similarity in the conserved N-terminal region to other moesin molecu ... Full text Cite

Quantitative switch in integrin expression accompanies differentiation of F9 cells treated with retinoic acid.

Journal Article Developmental dynamics : an official publication of the American Association of Anatomists · December 1994 F9 embryonal carcinoma cells resemble epithelial cells when in monolayer culture. After treatment with retinoic acid these cells differentiate into fibroblastic-like cells in a sequence that has been modeled as the mammalian equivalent of the differentiati ... Full text Cite

Skeletal pattern is specified autonomously by the primary mesenchyme cells in sea urchin embryos.

Journal Article Developmental biology · April 1994 In the sea urchin embryo the primary mesenchyme cells (PMCs) produce a CaCO3 skeleton in a pattern that is species specific. To establish whether skeletal pattern is specified autonomously by the PMCs or through instructive interactions with the ectoderm, ... Full text Cite

The establishment of bilateral asymmetry in sea urchin embryos

Journal Article Development · January 1, 1994 Although much is known about the specification and determination of the two primary axes (animal/vegetal and dorsoventral or oral/aboral) in a number of embryos, little is understood about bilaterality. In the sea urchin, left/right asymmetry is crucial to ... Cite

Cell-cell interactions regulate skeleton formation in the sea urchin embryo.

Journal Article Development (Cambridge, England) · November 1993 In the sea urchin embryo, the primary mesenchyme cells (PMCs) make extensive contact with the ectoderm of the blastula wall. This contact is shown to influence production of the larval skeleton by the PMCs. A previous observation showed that treatment of e ... Full text Cite

Commitment along the dorsoventral axis of the sea urchin embryo is altered in response to NiCl2.

Journal Article Development (Cambridge, England) · November 1992 Few treatments are known that perturb the dorsoventral axis of the sea urchin embryo. We report here that the dorsoventral polarity of the sea urchin embryo can be disrupted by treatment of embryos with NiCl2. Lytechinus variegatus embryos treated with 0.5 ... Full text Cite

Deployment of extracellular matrix proteins in sea urchin embryogenesis.

Journal Article Microscopy research and technique · June 1992 The apical extracellular matrix of the sea urchin embryo, known as the hyaline layer (HL), is a multi-laminate organelle composed of at least 10 polypeptides. Although integrated into one ECM, HL proteins exhibit individual temporal and spatial dynamics th ... Full text Cite

On the ultrastructure of hyalin, a cell adhesion protein of the sea urchin embryo extracellular matrix.

Journal Article The Journal of cell biology · March 1992 Hyalin is a large (ca. 350 x 10(3) kD by gel electrophoresis) molecule that contributes to the hyalin layer surrounding the sea urchin embryo. In previous work a mAb (McA Tg-HYL), specific for hyalin, was found to inhibit cell-hyalin adhesion and block mor ... Full text Cite

Pattern formation during gastrulation in the sea urchin embryo.

Journal Article Development (Cambridge, England). Supplement · January 1992 The sea urchin embryo follows a relatively simple cell behavioral sequence in its gastrulation movements. To form the mesoderm, primary mesenchyme cells ingress from the vegetal plate and then migrate along the basal lamina lining the blastocoel. The presu ... Cite

Pattern formation during gastrulation in the sea urchin embryo

Journal Article Development · January 1, 1992 The sea urchin embryo follows a relatively simple cell behavioral sequence in its gastrulation movements. To form the mesoderm, primary mesenchyme cells ingress from the vegetal plate and then migrate along the basal lamina lining the blastocoel. The presu ... Cite

Gastrulation.

Journal Article Current opinion in genetics & development · August 1991 At gastrulation, a single layer of cells is converted into an outer ectodermal covering, an inner ectodermal tube, and in triploblastic phyla, a middle mesodermal layer. This morphogenesis is driven by motility and directed by cell interactions, some of wh ... Full text Cite

Tissue-specific, temporal changes in cell adhesion to echinonectin in the sea urchin embryo.

Journal Article Developmental biology · April 1991 Echinonectin is a dimeric, glycoprotein found in the hyaline layer of the developing sea urchin embryo. It was found that echinonectin supports adhesion of embryonic cells in vitro. Previous studies have shown that the protein hyalin also supports adhesion ... Full text Cite

Target recognition by the archenteron during sea urchin gastrulation.

Journal Article Developmental biology · November 1990 During sea urchin gastrulation filopodia are sent out by secondary mesenchyme cells (SMCs) at the tip of the archenteron in continual cycles of extension, attachment, and retraction. Eventually the archenteron ceases its elongation and its tip localizes to ... Full text Cite

A hyaline layer protein that becomes localized to the oral ectoderm and foregut of sea urchin embryos.

Journal Article Developmental biology · July 1990 An antigen is described which is a marker for the oral ectoderm and foregut of the sea urchin embryo. In Lytechinus variegatus, the antigen is first detectable by immunofluorescence on the surface of fertilized eggs, and remains globally distributed throug ... Full text Cite

In vitro biological activities of echinonectin.

Journal Article Biochemistry · February 1990 Echinonectin (EN) is a 230-kDa extracellular matrix glycoprotein found in the hyaline layer of sea urchin embryos. Dissociated embryonic cells attached strongly to EN-coated microtiter wells in a centrifugal-based in vitro adhesion assay, suggesting that E ... Full text Cite

Neuronal-glial interactions: complexity of neurite outgrowth correlates with substrate adhesivity of serotonergic neurons.

Journal Article Glia · January 1990 To study the interactions between neurons of known transmitter phenotype and non-neuronal cells of glial or fibroblastic origin, serotonergic (5-HT) neurons were tested for their strength of adhesion and neurite outgrowth patterns on substrates of astrocyt ... Full text Cite

Cell adhesion to fibronectin and tenascin: quantitative measurements of initial binding and subsequent strengthening response.

Journal Article J Cell Biol · October 1989 Cell-substratum adhesion strengths have been quantified using fibroblasts and glioma cells binding to two extracellular matrix proteins, fibronectin and tenascin. A centrifugal force-based adhesion assay was used for the adhesive strength measurements, and ... Full text Link to item Cite

Cell adhesion to fibronectin and tenascin: quantitative measurements of initial binding and subsequent strengthening response.

Journal Article The Journal of cell biology · October 1989 Cell-substratum adhesion strengths have been quantified using fibroblasts and glioma cells binding to two extracellular matrix proteins, fibronectin and tenascin. A centrifugal force-based adhesion assay was used for the adhesive strength measurements, and ... Full text Cite

Embryonic cellular organization: differential restriction of fates as revealed by cell aggregates and lineage markers.

Journal Article The Journal of experimental zoology · August 1989 Cleavage-stage Lytechinus variegatus embryos were dissociated and the cells were aggregated in an experimental system designed to address questions of embryonic organizational capability. Using monoclonal antibodies against stage- and structure-specific an ... Full text Cite

Echinonectin: a new embryonic substrate adhesion protein.

Journal Article J Cell Biol · December 1988 An extracellular matrix molecule has been purified from sea urchin (Lytechinus variegatus) embryos. Based on its functional properties and on its origin, this glycoprotein has been given the name "echinonectin." Echinonectin is a 230-kD dimer with a unique ... Full text Link to item Cite

Cell polarity in sea urchin embryos: reorientation of cells occurs quickly in aggregates.

Journal Article Developmental biology · June 1988 Four apical components were used as markers for the apical end of the cell in studies centering on cell polarity in the early blastula stage of sea urchin embryos and in aggregates of cleavage stage cells. Cells were observed to maintain their polarity for ... Full text Cite

The origin of spicule-forming cells in a 'primitive' sea urchin (Eucidaris tribuloides) which appears to lack primary mesenchyme cells.

Journal Article Development (Cambridge, England) · June 1988 The calcareous larval skeleton of euechinoid sea urchins is synthesized by primary mesenchyme cells which ingress prior to gastrulation. In embryos of the cidaroid sea urchin Eucidaris tribuloides, no mesenchyme cells ingress before gastrulation, yet larva ... Full text Cite

Cell lineage conversion in the sea urchin embryo.

Journal Article Developmental biology · February 1988 The mesoderm of the sea urchin embryo conventionally is divided into two populations of cells; the primary mesenchyme cells (PMCs), which produce the larval skeleton, and the secondary mesenchyme cells (SMCs), which differentiate into a variety of cell typ ... Full text Cite

Echinonectin: A new embryonic substrate adhesion protein

Journal Article Journal of Cell Biology · January 1, 1988 An extracellular matrix molecule has been purified from sea urchin (Lytechinus variegatus) embryos. Based on its functional properties and on its origin, this glycoprotein has been given the name 'echinonectin'. Echinonectin is a 230-kD dimer with a unique ... Full text Cite

Storage and mobilization of extracellular matrix proteins during sea urchin development.

Journal Article Developmental biology · January 1988 After fertilization, sea urchin embryos surround themselves with an extracellular matrix, or hyaline layer, to which cells adhere during early development. Hyalin, the major protein component of the hyaline layer has been isolated and partially characteriz ... Full text Cite

A cortical granule-specific enzyme, B-1,3-glucanase, in sea urchin eggs.

Journal Article Gamete research · December 1987 The ultrastructural localization of B-1,3-glucanase in three species of sea urchin eggs was determined using a monospecific antibody in an electronmicroscopic immunogold procedure. In all three species, Lytechinus variegatus, Strongylocentrotus purpuratus, ... Full text Cite

Stage-specific expression of beta-1, 3-glucanase in sea urchin embryos and hybrids.

Journal Article The Journal of experimental zoology · November 1987 In some species of sea urchin, such as Lytechinus variegatus beta-1, 3-glucanase activity is present at two distinct developmental stages (in the unfertilized egg and again following gastrulation). There is a different form of the enzyme beta-1, 3-glucanas ... Full text Cite

Gastrulation in the sea urchin embryo requires the deposition of crosslinked collagen within the extracellular matrix.

Journal Article Developmental biology · May 1987 This study demonstrates that a collagenous extracellular matrix (ECM) is necessary for gastrulation in the sea urchin embryo. The approach taken was to disrupt collagen processing with two types of agents (a lathyritic agent, beta-aminopropionitrile (BAPN) ... Full text Cite

A new method for isolating primary mesenchyme cells of the sea urchin embryo. Panning on wheat germ agglutinin-coated dishes.

Journal Article Experimental cell research · February 1987 This paper describes a rapid and efficient way to isolate primary mesenchyme cells (PMCs) of the sea urchin embryo. The procedure involves three simple steps: Dissociation of mesenchyme blastulae in calcium-free artificial seawater. Incubation of the resul ... Full text Cite

Cell adhesion in morphogenesis.

Journal Article Annual review of cell biology · January 1987 Full text Cite

The regulation of primary mesenchyme cell migration in the sea urchin embryo: transplantations of cells and latex beads.

Journal Article Developmental biology · October 1986 After their ingression, the primary mesenchyme cells (PMCs) of the sea urchin embryo migrate within the blastocoel, where they eventually become arranged in a characteristic ring-like pattern. To gain information about how the movements of the PMCs are reg ... Full text Cite

On the role of calcium in the adhesion of embryonic sea urchin cells.

Journal Article Experimental cell research · July 1986 Calcium is shown to have several roles in the adhesion of embryonic sea urchin cells. Using an assay that subdivides a cell interaction into sequential steps it is shown that Ca2+ has distinct roles in at least two separate steps. The initial binding step ... Full text Cite

Two embryonic, tissue-specific molecules identified by a double-label immunofluorescence technique for monoclonal antibodies.

Journal Article The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society · June 1986 We identify two tissue-specific molecules in the sea urchin embryo by an immunofluorescence technique capable of co-localizing monoclonal antibodies on the same tissue section. The technique uses monovalent Fab-fluorochrome conjugates as secondary reagents ... Full text Cite

Two antigenically distinct forms of β-1,3-glucanase in sea urchin embryonic development

Journal Article Developmental Biology · January 1, 1986 The enzyme β-1,3-glucanase is contained in the unfertilized eggs of most species of sea urchin. In some species, including Lytechinus variegatus, there is also substantial activity following gastrulation, and during remaining larval development. To determi ... Full text Cite

Embryo dissociation, cell isolation, and cell reassociation.

Journal Article Methods in cell biology · January 1986 In resolving the role of cell recognition events in the process of morphogenesis it is necessary to focus on single events against a background of many complex interactions. This article presents a series of approaches that are designed to do just that. It ... Full text Cite

Sequential expression of germ-layer specific molecules in the sea urchin embryo.

Journal Article Developmental biology · October 1985 Described are two germ-layer specific molecules that appear coincident with the formation of two germ layer cell lineages in the sea urchin embryo. Meso1 is a molecule of 380 kDa that is first detected at the time of primary mesenchyme cell delamination fr ... Full text Cite

The surface of the sea urchin embryo at gastrulation: a molecular mosaic

Journal Article Trends in Genetics · January 1, 1985 A series of cellular rearrangements are observed during gastrulation of the sea urchin embryo. At the same time new cell surface molecules are expressed in a variety of patterns, many of which could serve as molecular cues for morphogenesis. © 1985. ... Full text Cite

Three cell recognition changes accompany the ingression of sea urchin primary mesenchyme cells.

Journal Article Developmental biology · January 1985 At gastrulation the primary mesenchyme cells of sea urchin embryos lose contact with the extracellular hyaline layer and with neighboring blastomeres as they pass through the basal lamina and enter the blastocoel. This delamination process was examined usi ... Full text Cite

Ontogeny of the basal lamina in the sea urchin embryo.

Journal Article Developmental biology · May 1984 The patterns of expression for several extracellular matrix components during development of the sea urchin embryo are described. An immunofluorescence assay was employed on paraffin-sectioned material using (i) polyclonal antibodies against known vertebra ... Full text Cite

Cell recognition processes in the differentiation of embryonic sea urchins.

Journal Article Progress in clinical and biological research · January 1984 Cite

Sea urchin hyalin: appearance and function in development.

Journal Article Developmental biology · August 1982 Full text Cite

Retinal ligatin recognizes glycoproteins bearing oligosaccharides terminating in phosphodiester-linked glucose.

Journal Article Cell · April 1982 Ligatin is a filamentous, baseplate protein that binds and localizes peripheral glycoproteins to the external cell surface. Glycoproteins coisolated with ligatin from embryonic chicken neural retina and radiolabeled with 32P are retained by an affinity col ... Full text Cite

A possible role for ligatin and the phosphoglycoproteins it binds in calcium-dependent retinal cell adhesion.

Journal Article Journal of cellular biochemistry · January 1982 Ligatin is a filamentous plasma membrane protein that serves as a baseplate for the attachment of peripheral glycoproteins to the external cell surface. Ligatin can be released from intact, embryonic chick neural retinal cells by treatment with 20 mM Ca++ ... Full text Cite

Calcium-dependent and calcium-independent adhesive mechanisms are present during initial binding events of neural retina cells.

Journal Article Journal of cellular biochemistry · January 1982 The hypothesis that intercellular adhesion can be subdivided into two separable phenomena, an initial recognition event and a subsequent stabilization, is supported by the use of a new cell binding assay that provides a quantitative measure of intercellula ... Full text Cite

Cell recognition during gastrulation in the sea urchin

Journal Article Cell Differentiation · January 1, 1982 Full text Cite

Intercellular recognition: quantitation of initial binding events.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 1981 The hypothesis that intercellular adhesion can be subdivided into two separable phenomena--an initial recognition event and a subsequent stabilization--is supported by the use of a cell binding assay that provides a quantitative measure of intercellular bi ... Full text Cite

Surface antigens involved in interactions of embryonic sea urchin cells.

Journal Article Current topics in developmental biology · January 1979 Full text Cite

A requirement for trypsin-sensitive cell-surface components for cell-cell interactions of embryonic neural retina cells.

Journal Article The Journal of cell biology · October 1977 A quantitative assay was used to measure the rate of collection of a population of embryonic neural retina cells to the surface of cell aggregates. The rate of collection of freshly trysinized cells was limited in the initial stages by the rate of replacem ... Full text Cite

A kinetic study of embryonic cell adhesion.

Journal Article Developmental biology · March 1975 Full text Cite

Cell aggregation: properties of cell surface factors from five species of sponge.

Journal Article The Journal of experimental zoology · April 1974 Full text Cite