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Masayuki Onishi

Assistant Professor of Biology
Biology
130 Science Dr., Box 90338, Durham, NC 27708
124 Science Dr., FFSC 3105, Durham, NC 27708

Selected Publications


Chloroplast Methyltransferase Homolog RMT2 is Involved in Photosystem I Biogenesis.

Journal Article bioRxiv · April 5, 2024 Oxygen (O2), a dominant element in the atmosphere and essential for most life on Earth, is produced by the photosynthetic oxidation of water. However, metabolic activity can cause accumulation of reactive O2 species (ROS) and severe cell damage. To identif ... Full text Link to item Cite

The Evolutionary Origins and Ancestral Features of Septins.

Journal Article bioRxiv · March 27, 2024 Septins are a family of membrane-associated cytoskeletal GTPases that play crucial roles in various cellular processes, such as cell division, phagocytosis, and organelle fission. Despite their importance, the evolutionary origins and ancestral function of ... Full text Link to item Cite

A chloroplast protein atlas reveals punctate structures and spatial organization of biosynthetic pathways.

Journal Article Cell · August 2023 Chloroplasts are eukaryotic photosynthetic organelles that drive the global carbon cycle. Despite their importance, our understanding of their protein composition, function, and spatial organization remains limited. Here, we determined the localizations of ... Full text Cite

The cellular cytoskeleton

Chapter · January 1, 2023 This chapter discusses the three cytoskeletal elements found in the cell body of Chlamydomonas; they are microtubules, filamentous (F-) actin, and septin. For microtubules and F-actin, it covers the multiple structures formed during vegetative growth and c ... Full text Cite

Control of division in Chlamydomonas by cyclin B/CDKB1 and the anaphase-promoting complex.

Journal Article PLoS genetics · August 2022 In yeast and animals, cyclin B binds and activates the cyclin-dependent kinase ('CDK') CDK1 to drive entry into mitosis. We show that CYCB1, the sole cyclin B in Chlamydomonas, activates the plant-specific CDKB1 rather than the CDK1 ortholog CDKA1, confirm ... Full text Cite

Systematic characterization of gene function in the photosynthetic alga Chlamydomonas reinhardtii.

Journal Article Nature genetics · May 2022 Most genes in photosynthetic organisms remain functionally uncharacterized. Here, using a barcoded mutant library of the model eukaryotic alga Chlamydomonas reinhardtii, we determined the phenotypes of more than 58,000 mutants under more than 121 different ... Full text Cite

Insights into coral bleaching under heat stress from analysis of gene expression in a sea anemone model system.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2020 Featured Publication Loss of endosymbiotic algae ("bleaching") under heat stress has become a major problem for reef-building corals worldwide. To identify genes that might be involved in triggering or executing bleaching, or in protecting corals from it, we used RNAseq to ana ... Full text Cite

Cleavage-furrow formation without F-actin in Chlamydomonas.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2020 Featured Publication It is widely believed that cleavage-furrow formation during cytokinesis is driven by the contraction of a ring containing F-actin and type-II myosin. However, even in cells that have such rings, they are not always essential for furrow formation. Moreover, ... Full text Cite

Systematic characterization of gene function in a photosynthetic organism

Journal Article bioRxiv · January 1, 2020 Photosynthetic organisms are essential for human life, yet most of their genes remain functionally uncharacterized. Single-celled photosynthetic model systems have the potential to accelerate our ability to connect genes to functions. Here, using a barcode ... Full text Link to item Cite

Transfer of the Septin Ring to Cytokinetic Remnants in ER Stress Directs Age-Sensitive Cell-Cycle Re-entry.

Journal Article Developmental cell · October 2019 During cell division, the inheritance of a functional endoplasmic reticulum (ER) is ensured by the endoplasmic reticulum stress surveillance (ERSU) pathway. Activation of ERSU causes the septin ring to mislocalize, which blocks ER inheritance and cytokines ... Full text Cite

F-actin homeostasis through transcriptional regulation and proteasome-mediated proteolysis.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2018 Featured Publication Many organisms possess multiple and often divergent actins whose regulation and roles are not understood in detail. For example, Chlamydomonas reinhardtii has both a conventional actin (IDA5) and a highly divergent one (NAP1); only IDA5 is expressed ... Full text Cite

Role of the Hof1-Cyk3 interaction in cleavage-furrow ingression and primary-septum formation during yeast cytokinesis.

Journal Article Molecular biology of the cell · March 2018 Featured Publication In Saccharomyces cerevisiae, it is well established that Hof1, Cyk3, and Inn1 contribute to septum formation and cytokinesis. Because hof1∆ and cyk3∆ single mutants have relatively mild defects but hof1∆ cyk3∆ double mutants are ... Full text Cite

Glucose-Induced Trophic Shift in an Endosymbiont Dinoflagellate with Physiological and Molecular Consequences.

Journal Article Plant physiology · February 2018 Interactions between the dinoflagellate endosymbiont Symbiodinium and its cnidarian hosts (e.g. corals, sea anemones) are the foundation of coral-reef ecosystems. Carbon flow between the partners is a hallmark of this mutualism, but the mechanisms g ... Full text Cite

Robust Transgene Expression from Bicistronic mRNA in the Green Alga Chlamydomonas reinhardtii.

Journal Article G3 (Bethesda, Md.) · December 2016 The unicellular green alga Chlamydomonas reinhardtii is a model organism that provides an opportunity to understand the evolution and functional biology of the lineage that includes the land plants, as well as aspects of the fundamental core biology conser ... Full text Cite

RNA-binding protein DUS16 plays an essential role in primary miRNA processing in the unicellular alga Chlamydomonas reinhardtii.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · September 2016 Canonical microRNAs (miRNAs) are embedded in duplexed stem-loops in long precursor transcripts and are excised by sequential cleavage by DICER nuclease(s). In this miRNA biogenesis pathway, dsRNA-binding proteins play important roles in animals and plants ... Full text Cite

Timely Endocytosis of Cytokinetic Enzymes Prevents Premature Spindle Breakage during Mitotic Exit.

Journal Article PLoS genetics · July 2016 Cytokinesis requires the spatio-temporal coordination of membrane deposition and primary septum (PS) formation at the division site to drive acto-myosin ring (AMR) constriction. It has been demonstrated that AMR constriction invariably occurs only after th ... Full text Cite

ASH1L Links Histone H3 Lysine 36 Dimethylation to MLL Leukemia.

Journal Article Cancer discovery · July 2016 UnlabelledNumerous studies in multiple systems support that histone H3 lysine 36 dimethylation (H3K36me2) is associated with transcriptional activation; however, the underlying mechanisms are not well defined. Here, we show that the H3K36me2 chrom ... Full text Cite

Chloroplast Methyltransferase Homolog RMT2 is Involved in Photosystem I Biogenesis.

Journal Article bioRxiv · April 5, 2024 Oxygen (O2), a dominant element in the atmosphere and essential for most life on Earth, is produced by the photosynthetic oxidation of water. However, metabolic activity can cause accumulation of reactive O2 species (ROS) and severe cell damage. To identif ... Full text Link to item Cite

The Evolutionary Origins and Ancestral Features of Septins.

Journal Article bioRxiv · March 27, 2024 Septins are a family of membrane-associated cytoskeletal GTPases that play crucial roles in various cellular processes, such as cell division, phagocytosis, and organelle fission. Despite their importance, the evolutionary origins and ancestral function of ... Full text Link to item Cite

A chloroplast protein atlas reveals punctate structures and spatial organization of biosynthetic pathways.

Journal Article Cell · August 2023 Chloroplasts are eukaryotic photosynthetic organelles that drive the global carbon cycle. Despite their importance, our understanding of their protein composition, function, and spatial organization remains limited. Here, we determined the localizations of ... Full text Cite

The cellular cytoskeleton

Chapter · January 1, 2023 This chapter discusses the three cytoskeletal elements found in the cell body of Chlamydomonas; they are microtubules, filamentous (F-) actin, and septin. For microtubules and F-actin, it covers the multiple structures formed during vegetative growth and c ... Full text Cite

Control of division in Chlamydomonas by cyclin B/CDKB1 and the anaphase-promoting complex.

Journal Article PLoS genetics · August 2022 In yeast and animals, cyclin B binds and activates the cyclin-dependent kinase ('CDK') CDK1 to drive entry into mitosis. We show that CYCB1, the sole cyclin B in Chlamydomonas, activates the plant-specific CDKB1 rather than the CDK1 ortholog CDKA1, confirm ... Full text Cite

Systematic characterization of gene function in the photosynthetic alga Chlamydomonas reinhardtii.

Journal Article Nature genetics · May 2022 Most genes in photosynthetic organisms remain functionally uncharacterized. Here, using a barcoded mutant library of the model eukaryotic alga Chlamydomonas reinhardtii, we determined the phenotypes of more than 58,000 mutants under more than 121 different ... Full text Cite

Insights into coral bleaching under heat stress from analysis of gene expression in a sea anemone model system.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2020 Featured Publication Loss of endosymbiotic algae ("bleaching") under heat stress has become a major problem for reef-building corals worldwide. To identify genes that might be involved in triggering or executing bleaching, or in protecting corals from it, we used RNAseq to ana ... Full text Cite

Cleavage-furrow formation without F-actin in Chlamydomonas.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2020 Featured Publication It is widely believed that cleavage-furrow formation during cytokinesis is driven by the contraction of a ring containing F-actin and type-II myosin. However, even in cells that have such rings, they are not always essential for furrow formation. Moreover, ... Full text Cite

Systematic characterization of gene function in a photosynthetic organism

Journal Article bioRxiv · January 1, 2020 Photosynthetic organisms are essential for human life, yet most of their genes remain functionally uncharacterized. Single-celled photosynthetic model systems have the potential to accelerate our ability to connect genes to functions. Here, using a barcode ... Full text Link to item Cite

Transfer of the Septin Ring to Cytokinetic Remnants in ER Stress Directs Age-Sensitive Cell-Cycle Re-entry.

Journal Article Developmental cell · October 2019 During cell division, the inheritance of a functional endoplasmic reticulum (ER) is ensured by the endoplasmic reticulum stress surveillance (ERSU) pathway. Activation of ERSU causes the septin ring to mislocalize, which blocks ER inheritance and cytokines ... Full text Cite

F-actin homeostasis through transcriptional regulation and proteasome-mediated proteolysis.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2018 Featured Publication Many organisms possess multiple and often divergent actins whose regulation and roles are not understood in detail. For example, Chlamydomonas reinhardtii has both a conventional actin (IDA5) and a highly divergent one (NAP1); only IDA5 is expressed ... Full text Cite

Role of the Hof1-Cyk3 interaction in cleavage-furrow ingression and primary-septum formation during yeast cytokinesis.

Journal Article Molecular biology of the cell · March 2018 Featured Publication In Saccharomyces cerevisiae, it is well established that Hof1, Cyk3, and Inn1 contribute to septum formation and cytokinesis. Because hof1∆ and cyk3∆ single mutants have relatively mild defects but hof1∆ cyk3∆ double mutants are ... Full text Cite

Glucose-Induced Trophic Shift in an Endosymbiont Dinoflagellate with Physiological and Molecular Consequences.

Journal Article Plant physiology · February 2018 Interactions between the dinoflagellate endosymbiont Symbiodinium and its cnidarian hosts (e.g. corals, sea anemones) are the foundation of coral-reef ecosystems. Carbon flow between the partners is a hallmark of this mutualism, but the mechanisms g ... Full text Cite

Robust Transgene Expression from Bicistronic mRNA in the Green Alga Chlamydomonas reinhardtii.

Journal Article G3 (Bethesda, Md.) · December 2016 The unicellular green alga Chlamydomonas reinhardtii is a model organism that provides an opportunity to understand the evolution and functional biology of the lineage that includes the land plants, as well as aspects of the fundamental core biology conser ... Full text Cite

RNA-binding protein DUS16 plays an essential role in primary miRNA processing in the unicellular alga Chlamydomonas reinhardtii.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · September 2016 Canonical microRNAs (miRNAs) are embedded in duplexed stem-loops in long precursor transcripts and are excised by sequential cleavage by DICER nuclease(s). In this miRNA biogenesis pathway, dsRNA-binding proteins play important roles in animals and plants ... Full text Cite

Timely Endocytosis of Cytokinetic Enzymes Prevents Premature Spindle Breakage during Mitotic Exit.

Journal Article PLoS genetics · July 2016 Cytokinesis requires the spatio-temporal coordination of membrane deposition and primary septum (PS) formation at the division site to drive acto-myosin ring (AMR) constriction. It has been demonstrated that AMR constriction invariably occurs only after th ... Full text Cite

ASH1L Links Histone H3 Lysine 36 Dimethylation to MLL Leukemia.

Journal Article Cancer discovery · July 2016 UnlabelledNumerous studies in multiple systems support that histone H3 lysine 36 dimethylation (H3K36me2) is associated with transcriptional activation; however, the underlying mechanisms are not well defined. Here, we show that the H3K36me2 chrom ... Full text Cite

Evidence That an Unconventional Actin Can Provide Essential F-Actin Function and That a Surveillance System Monitors F-Actin Integrity in Chlamydomonas.

Journal Article Genetics · March 2016 Featured Publication Actin is one of the most conserved eukaryotic proteins. It is thought to have multiple essential cellular roles and to function primarily or exclusively as filaments ("F-actin"). Chlamydomonas has been an enigma, because a null mutation (ida5-1) in its sin ... Full text Cite

The nonopisthokont septins: How many there are, how little we know about them, and how we might learn more.

Chapter · January 2016 Featured Publication We have confirmed and extended previous reports of a wide distribution of septin proteins in the eukaryotic phylogeny. It now appears that septins are present in at least some representatives of every eukaryotic supergroup, with the possible exception of t ... Full text Cite

Relative Contributions of Various Cellular Mechanisms to Loss of Algae during Cnidarian Bleaching.

Journal Article PloS one · January 2016 When exposed to stress such as high seawater temperature, corals and other cnidarians can bleach due to loss of symbiotic algae from the host tissue and/or loss of pigments from the algae. Although the environmental conditions that trigger bleaching are re ... Full text Cite

Analysis of Rho-GTPase Activity During Budding Yeast Cytokinesis.

Chapter · January 2016 Rho-type small GTPases are involved in cytokinesis in various organisms, but their precise roles and regulation remain unclear. Rho proteins function as molecular switches by cycling between the active GTP-bound and inactive GDP-bound states; the GTP-bound ... Full text Cite

Cytokinesis breaks dicentric chromosomes preferentially at pericentromeric regions and telomere fusions.

Journal Article Genes & development · February 2015 Dicentric chromosomes are unstable products of erroneous DNA repair events that can lead to further genome rearrangements and extended gene copy number variations. During mitosis, they form anaphase bridges, resulting in chromosome breakage by an unknown m ... Full text Cite

Actin is required for IFT regulation in Chlamydomonas reinhardtii.

Journal Article Current biology : CB · September 2014 Assembly of cilia and flagella requires intraflagellar transport (IFT), a highly regulated kinesin-based transport system that moves cargo from the basal body to the tip of flagella [1]. The recruitment of IFT components to basal bodies is a function of fl ... Full text Cite

Distinct roles of Rho1, Cdc42, and Cyk3 in septum formation and abscission during yeast cytokinesis.

Journal Article The Journal of cell biology · July 2013 Featured Publication In yeast and animal cytokinesis, the small guanosine triphosphatase (GTPase) Rho1/RhoA has an established role in formation of the contractile actomyosin ring, but its role, if any, during cleavage-furrow ingression and abscission is poorly understood. Thr ... Full text Cite

Fission yeast Cyk3p is a transglutaminase-like protein that participates in cytokinesis and cell morphogenesis.

Journal Article Molecular biology of the cell · July 2012 Cell morphogenesis is a complex process that relies on a diverse array of proteins and pathways. We have identified a transglutaminase-like protein (Cyk3p) that functions in fission yeast morphogenesis. The phenotype of a cyk3 knockout strain indicates a p ... Full text Cite

New insights into the phylogenetic distribution and evolutionary origins of the septins.

Journal Article Biological chemistry · August 2011 Until recently, it had appeared that the septin family of proteins was restricted to the opisthokont eukaryotes (the fungi and animals and their close relatives the microsporidia and choanoflagellates). It has now become apparent that septins are also pres ... Full text Cite

Evidence that a septin diffusion barrier is dispensable for cytokinesis in budding yeast.

Journal Article Biological chemistry · August 2011 Septins are essential for cytokinesis in Saccharomyces cerevisiae, but their precise roles remain elusive. Currently, it is thought that before cytokinesis, the hourglass-shaped septin structure at the mother-bud neck acts as a scaffold for assembly of the ... Full text Cite

Role of septins in the orientation of forespore membrane extension during sporulation in fission yeast.

Journal Article Molecular and cellular biology · April 2010 Featured Publication During yeast sporulation, a forespore membrane (FSM) initiates at each spindle-pole body and extends to form the spore envelope. We used Schizosaccharomyces pombe to investigate the role of septins during this process. During the prior conjugation of haplo ... Full text Cite

Role of Inn1 and its interactions with Hof1 and Cyk3 in promoting cleavage furrow and septum formation in S. cerevisiae.

Journal Article The Journal of cell biology · June 2009 Featured Publication Cytokinesis requires coordination of actomyosin ring (AMR) contraction with rearrangements of the plasma membrane and extracellular matrix. In Saccharomyces cerevisiae, new membrane, the chitin synthase Chs2 (which forms the primary septum [PS]), and the p ... Full text Cite

Schizosaccharomyces pombe Sst4p, a conserved Vps27/Hrs homolog, functions downstream of phosphatidylinositol 3-kinase Pik3p to mediate proper spore formation.

Journal Article Eukaryotic cell · December 2007 Sporulation of the fission yeast Schizosaccharomyces pombe is a developmental process that generates gametes and that includes the formation of spore envelope precursors called the forespore membranes. Assembly and development of forespore membranes requir ... Full text Cite

Essential roles of class E Vps proteins for sorting into multivesicular bodies in Schizosaccharomyces pombe.

Journal Article Microbiology (Reading, England) · August 2007 The multivesicular body (MVB) sorting pathway is required for a number of biological processes, including downregulation of cell-surface proteins and protein sorting into the vacuolar lumen. The function of this pathway requires endosomal sorting complexes ... Full text Cite

Sorting nexin homologues are targets of phosphatidylinositol 3-phosphate in sporulation of Schizosaccharomyces pombe.

Journal Article Genes to cells : devoted to molecular & cellular mechanisms · June 2004 Schizosaccharomyces pombe defective in phosphatidylinositol (PtdIns) 3-kinase shows various defects in forespore membrane formation, including onset, growth orientation, and closure. Downstream factors of PtdIns 3-kinase in this system were explored. Among ... Full text Cite

Isolation of suppressor mutants of phosphatidylinositol 3-phosphate 5-kinase deficient cells in Schizosaccharomyces pombe.

Journal Article Bioscience, biotechnology, and biochemistry · August 2003 The ste12+ gene of Schizosaccharomyces pombe codes for a phosphatidylinositol (PI) 3-phosphate 5'-kinase, which is required for efficient mating. Suppressor mutants for sterility of ste12Delta cells were screened for. Most of the mutant genes turned out to ... Full text Cite

Characterization of vps33+, a gene required for vacuolar biogenesis and protein sorting in Schizosaccharomyces pombe.

Journal Article Yeast (Chichester, England) · July 2003 From the fission yeast Schizosaccharomyces pombe we have identified and deleted vps33, a gene encoding a homologue of VPS33, which is required for vacuolar biogenesis in S. cerevisiae cells. When the vps33(+) gene is disrupted, Sz. pombe strains are temper ... Full text Cite

Role of phosphatidylinositol 3-phosphate in formation of forespore membrane in Schizosaccharomyces pombe.

Journal Article Yeast (Chichester, England) · February 2003 Phosphatidylinositol (PI) 3-kinase (encoded by the pik3(+) gene) in Schizosaccharomyces pombe has been identified as a homologue of VPS34p, a protein required for proper vesicular protein sorting. The clone defective in this protein carries enlarged vacuol ... Full text Cite