Scholars@Duke
Sally A. Kornbluth

Sally A. Kornbluth

Jo Rae Wright University Distinguished Professor Emerita
Biology
kornb001@mc.duke.edu
90005, Durham, NC 27708
421 Chapel Drive, 220 Allen Building, Durham, NC 27708

Selected Publications

Dimer-specific immunoprecipitation of active caspase-2 identifies TRAF proteins as novel activators.

Journal Article The EMBO journal · July 2018 Caspase-2 has been shown to initiate apoptotic cell death in response to specific intracellular stressors such as DNA damage. However, the molecular mechanisms immediately upstream of its activation are still poorly understood. We combined a caspase-2 bimo ... Full text Cite

Downregulation of the proapoptotic protein MOAP-1 by the UBR5 ubiquitin ligase and its role in ovarian cancer resistance to cisplatin.

Journal Article Oncogene · March 2017 Evasion of apoptosis allows many cancers to resist chemotherapy. Apoptosis is mediated by the serial activation of caspase family proteins. These proteases are often activated upon the release of cytochrome c from the mitochondria, which is promoted by the ... Full text Cite

A grafted ovarian fragment rescues host fertility after chemotherapy.

Journal Article Mol Hum Reprod · December 2016 STUDY QUESTION: Can host fertility be rescued by grafting of a fragment of a healthy ovary soon after chemotherapy? SUMMARY ANSWER: We found that grafting a green fluorescent protein (GFP)-positive fragment from a healthy isogenic ovary to the left ovary o ... Full text Link to item Cite

Mitotic phosphatase activity is required for MCC maintenance during the spindle checkpoint.

Journal Article Cell cycle (Georgetown, Tex.) · January 2016 The spindle checkpoint prevents activation of the anaphase-promoting complex (APC/C) until all chromosomes are correctly attached to the mitotic spindle. Early in mitosis, the mitotic checkpoint complex (MCC) inactivates the APC/C by binding the APC/C acti ... Full text Cite

Vertebrate Reproduction.

Journal Article Cold Spring Harbor perspectives in biology · October 2015 Vertebrate reproduction requires a myriad of precisely orchestrated events-in particular, the maternal production of oocytes, the paternal production of sperm, successful fertilization, and initiation of early embryonic cell divisions. These processes are ... Full text Cite

Reduced lipoapoptosis, hedgehog pathway activation and fibrosis in caspase-2 deficient mice with non-alcoholic steatohepatitis.

Journal Article Gut · July 2015 OBJECTIVE: Caspase-2 is an initiator caspase involved in multiple apoptotic pathways, particularly in response to specific intracellular stressors (eg, DNA damage, ER stress). We recently reported that caspase-2 was pivotal for the induction of cell death ... Full text Link to item Cite

Fatty acid synthase inhibition engages a novel caspase-2 regulatory mechanism to induce ovarian cancer cell death.

Journal Article Oncogene · June 2015 Blockade of fatty acid synthase (FASN), a key enzyme involved in de novo lipogenesis, results in robust death of ovarian cancer cells. However, known FASN inhibitors have proven to be poor therapeutic agents due to their ability to induce cachexia. Therefo ... Full text Cite

Metabolic control of Ca2+/calmodulin-dependent protein kinase II (CaMKII)-mediated caspase-2 suppression by the B55β/protein phosphatase 2A (PP2A).

Journal Article J Biol Chem · December 26, 2014 High levels of metabolic activity confer resistance to apoptosis. Caspase-2, an apoptotic initiator, can be suppressed by high levels of nutrient flux through the pentose phosphate pathway. This metabolic control is exerted via inhibitory phosphorylation o ... Full text Link to item Cite

The complex interplay between metabolism and apoptosis

Journal Article · November 1, 2014 Energy balance is essential for cells to function properly and proliferate. Sufficient nutrient quantities are required for energy and the synthesis of building blocks of cellular structures such as lipid membranes, proteins, and nucleic acids. In contrast ... Full text Cite

Sally Kornbluth: Nature's incredible contraptions.

Journal Article The Journal of cell biology · July 2014 Full text Cite

The deubiquitinating enzyme DUBAI stabilizes DIAP1 to suppress Drosophila apoptosis.

Journal Article Cell Death Differ · April 2014 Deubiquitinating enzymes (DUBs) counteract ubiquitin ligases to modulate the ubiquitination and stability of target signaling molecules. In Drosophila, the ubiquitin-proteasome system has a key role in the regulation of apoptosis, most notably, by controll ... Full text Link to item Cite

Fatty acid synthase inhibition engages a novel caspase-2 regulatory mechanism to induce ovarian cancer cell death

Journal Article Oncogene · 2014 Blockade of fatty acid synthase (FASN), a key enzyme involved in de novo lipogenesis, results in robust death of ovarian cancer cells. However, known FASN inhibitors have proven to be poor therapeutic agents due to their ability to induce cachexia. Therefo ... Full text Cite

Suppression of DNA-damage checkpoint signaling by Rsk-mediated phosphorylation of Mre11.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2013 Ataxia telangiectasia mutant (ATM) is an S/T-Q-directed kinase that is critical for the cellular response to double-stranded breaks (DSBs) in DNA. Following DNA damage, ATM is activated and recruited by the MRN protein complex [meiotic recombination 11 (Mr ... Full text Open Access Cite

Metabolomic profiling reveals a role for caspase-2 in lipoapoptosis.

Journal Article J Biol Chem · May 17, 2013 The accumulation of long-chain fatty acids (LCFAs) in non-adipose tissues results in lipid-induced cytotoxicity (or lipoapoptosis). Lipoapoptosis has been proposed to play an important role in the pathogenesis of several metabolic diseases, including non-a ... Full text Link to item Cite

A network of substrates of the E3 ubiquitin ligases MDM2 and HUWE1 control apoptosis independently of p53.

Journal Article Sci Signal · May 7, 2013 In the intrinsic pathway of apoptosis, cell-damaging signals promote the release of cytochrome c from mitochondria, triggering activation of the Apaf-1 and caspase-9 apoptosome. The ubiquitin E3 ligase MDM2 decreases the stability of the proapoptotic facto ... Full text Open Access Link to item Cite

Engineering a BCR-ABL-activated caspase for the selective elimination of leukemic cells.

Journal Article Proc Natl Acad Sci U S A · February 5, 2013 Increased understanding of the precise molecular mechanisms involved in cell survival and cell death signaling pathways offers the promise of harnessing these molecules to eliminate cancer cells without damaging normal cells. Tyrosine kinase oncoproteins p ... Full text Open Access Link to item Cite

The tangled circuitry of metabolism and apoptosis.

Journal Article Molecular cell · February 2013 For single-cell organisms, nutrient uptake and metabolism are central to the fundamental decision of whether to grow or divide. In metazoans, cell fate decisions are more complex: organismal homeostasis must be strictly maintained by balancing cell prolife ... Full text Cite

Cellular mechanisms controlling caspase activation and function

Journal Article Cold Spring Harbor Perspectives in Medicine · 2013 Caspases are the primary drivers of apoptotic cell death, cleaving cellular proteins that are critical for dismantling the dying cell. Initially translated as inactive zymogenic precursors, caspases are activated in response to a variety of cell death stim ... Cite

Cellular mechanisms controlling caspase activation and function

Journal Article Cold Spring Harbor Perspectives in Medicine · January 1, 2013 Caspases are the primary drivers of apoptotic cell death, cleaving cellular proteins that are critical for dismantling the dying cell. Initially translated as inactive zymogenic precursors, caspases are activated in response to a variety of cell death stim ... Cite

Ubiquitylation of p53 by the APC/C inhibitor Trim39.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2012 Tripartite motif 39 (Trim39) is a RING domain-containing E3 ubiquitin ligase able to inhibit the anaphase-promoting complex (APC/C) directly. Through analysis of Trim39 function in p53-positive and p53-negative cells, we have found, surprisingly, that p53- ... Full text Open Access Cite

Life, death, and the metabolically controlled protein acetylome.

Journal Article Current opinion in cell biology · December 2012 The complex signaling pathways that control cellular fate can be intimately influenced by metabolic status. Although the ability of nutrients to influence intracellular decisions has been appreciated for some time, the complex signaling mechanisms linking ... Full text Cite

Mcl-1 rescues a glitch in the matrix.

Journal Article Nature cell biology · May 2012 Bcl-2 family proteins are known to control cell death and influence mitochondrial function. The function of Mcl-1, an anti-apoptotic Bcl-2 protein, is now shown to depend on its subcellular localization. Mcl-1 at the mitochondrial outer membrane inhibits m ... Full text Cite

The Trim39 ubiquitin ligase inhibits APC/CCdh1-mediated degradation of the Bax activator MOAP-1.

Journal Article The Journal of cell biology · April 2012 Proapoptotic Bcl-2 family members, such as Bax, promote release of cytochrome c from mitochondria, leading to caspase activation and cell death. It was previously reported that modulator of apoptosis protein 1 (MOAP-1), an enhancer of Bax activation induce ... Full text Open Access Cite

Rsk-mediated phosphorylation and 14-3-3É› binding of Apaf-1 suppresses cytochrome c-induced apoptosis.

Journal Article The EMBO journal · March 2012 Many pro-apoptotic signals trigger mitochondrial cytochrome c release, leading to caspase activation and ultimate cellular breakdown. Cell survival pathways, including the mitogen-activated protein kinase (MAPK) cascade, promote cell viability by impeding ... Full text Cite

Phosphatases driving mitosis: pushing the gas and lifting the brakes.

Journal Article Progress in molecular biology and translational science · January 2012 Entry into and progression through mitosis depends critically on the establishment and maintenance of protein phosphorylation. For this reason, studies on mitotic progression have focused heavily on the activation of MPF (M phase promoting factor), a cycli ... Full text Cite

Mitochondrial fusion is regulated by Reaper to modulate Drosophila programmed cell death.

Journal Article Cell Death Differ · October 2011 In most multicellular organisms, the decision to undergo programmed cell death in response to cellular damage or developmental cues is typically transmitted through mitochondria. It has been suggested that an exception is the apoptotic pathway of Drosophil ... Full text Open Access Link to item Cite

A biotin switch-based proteomics approach identifies 14-3-3ζ as a target of Sirt1 in the metabolic regulation of caspase-2.

Journal Article Mol Cell · September 2, 2011 While lysine acetylation in the nucleus is well characterized, comparatively little is known about its significance in cytoplasmic signaling. Here we show that inhibition of the Sirt1 deacetylase, which is primarily cytoplasmic in cancer cell lines, sensit ... Full text Link to item Cite

Meeting the (N-terminal) end with acetylation.

Journal Article Cell · August 2011 Cell-fate decisions are tightly linked to cellular energy status. In this issue, Yi et al. (2011) introduce a mechanism by which Bcl-xL lowers the threshold for apoptosis by suppressing acetyl-CoA production, which, in turn, suppresses the N-alpha-acetylat ... Full text Cite

Regulation of mitochondrial morphology by APC/CCdh1-mediated control of Drp1 stability.

Journal Article Mol Biol Cell · April 15, 2011 Homeostatic maintenance of cellular mitochondria requires a dynamic balance between fission and fusion, and controlled changes in morphology are important for processes such as apoptosis and cellular division. Interphase mitochondria have been described as ... Full text Link to item Cite

Regulation of the ATM-activator protein Aven by CRM1-dependent nuclear export.

Journal Article Cell cycle (Georgetown, Tex.) · October 2010 Aven is a regulator of apoptosis whose overexpression is associated with poor prognosis in several cancers, including childhood acute lymphoblastic leukemia and acute myeloid leukemia. We have recently shown that Aven serves as an activator and substrate o ... Full text Cite

The engine driving the ship: metabolic steering of cell proliferation and death.

Journal Article Nature reviews. Molecular cell biology · October 2010 Metabolic activity is a crucial determinant of a cell's decision to proliferate or die. Although it is not fully understood how metabolic pathways such as glycolysis and the pentose phosphate pathway communicate to cell cycle and apoptotic effectors, it is ... Full text Cite

Metabolic regulation of Drosophila apoptosis through inhibitory phosphorylation of Dronc.

Journal Article The EMBO journal · September 2010 Apoptosis ensures tissue homeostasis in response to developmental cues or cellular damage. Recently reported genome-wide RNAi screens have suggested that several metabolic regulators can modulate caspase activation in Drosophila. Here, we establish a previ ... Full text Cite

Emi2-mediated inhibition of E2-substrate ubiquitin transfer by the anaphase-promoting complex/cyclosome through a D-box-independent mechanism.

Journal Article Molecular biology of the cell · August 2010 Vertebrate eggs are arrested at Metaphase II by Emi2, the meiotic anaphase-promoting complex/cyclosome (APC/C) inhibitor. Although the importance of Emi2 during oocyte maturation has been widely recognized and its regulation extensively studied, its mechan ... Full text Open Access Cite

Stalling in mitosis and releasing the apoptotic brake.

Journal Article The EMBO journal · July 2010 Full text Cite

Features of programmed cell death in intact Xenopus oocytes and early embryos revealed by near-infrared fluorescence and real-time monitoring.

Journal Article Cell death and differentiation · January 2010 Factors influencing apoptosis of vertebrate eggs and early embryos have been studied in cell-free systems and in intact embryos by analyzing individual apoptotic regulators or caspase activation in static samples. A novel method for monitoring caspase acti ... Full text Open Access Cite

Protein phosphatase 2A-dependent dephosphorylation of replication protein A is required for the repair of DNA breaks induced by replication stress.

Journal Article Mol Cell Biol · November 2009 Eukaryotic genomic integrity is safeguarded by cell cycle checkpoints and DNA repair pathways, collectively known as the DNA damage response, wherein replication protein A (RPA) is a key regulator playing multiple critical roles. The genotoxic insult-induc ... Full text Link to item Cite

Restraint of apoptosis during mitosis through interdomain phosphorylation of caspase-2.

Journal Article EMBO J · October 21, 2009 The apoptotic initiator caspase-2 has been implicated in oocyte death, in DNA damage- and heat shock-induced death, and in mitotic catastrophe. We show here that the mitosis-promoting kinase, cdk1-cyclin B1, suppresses apoptosis upstream of mitochondrial c ... Full text Link to item Cite

A cut above the other caspases.

Journal Article Molecular cell · September 2009 In this issue of Molecular Cell, Bouchier-Hayes et al. (2009) develop a novel approach to visualizing caspase-2 activation in real time, enabling resolution of several controversies surrounding the position of this enzyme in apoptotic signaling cascades. ... Full text Cite

Caspases and kinases in a death grip.

Journal Article Cell · September 2009 The complex process of apoptosis is orchestrated by caspases, a family of cysteine proteases with unique substrate specificities. Accumulating evidence suggests that cell death pathways are finely tuned by multiple signaling events, including direct phosph ... Full text Cite

Guidelines for the use and interpretation of assays for monitoring cell death in higher eukaryotes.

Journal Article Cell death and differentiation · August 2009 Cell death is essential for a plethora of physiological processes, and its deregulation characterizes numerous human diseases. Thus, the in-depth investigation of cell death and its mechanisms constitutes a formidable challenge for fundamental and applied ... Full text Cite

Metabolic control of oocyte apoptosis mediated by 14-3-3zeta-regulated dephosphorylation of caspase-2.

Journal Article Developmental cell · June 2009 Xenopus oocyte death is partly controlled by the apoptotic initiator caspase-2 (C2). We reported previously that oocyte nutrient depletion activates C2 upstream of mitochondrial cytochrome c release. Conversely, nutrient-replete oocytes inhibit C2 via S135 ... Full text Cite

PP1-mediated dephosphorylation of phosphoproteins at mitotic exit is controlled by inhibitor-1 and PP1 phosphorylation.

Journal Article Nature cell biology · May 2009 Loss of cell division cycle 2 (Cdc2, also known as Cdk1) activity after cyclin B degradation is necessary, but not sufficient, for mitotic exit. Proteins phosphorylated by Cdc2 and downstream mitotic kinases must be dephosphorylated. We report here that pr ... Full text Cite

An essential role for the Glut1 PDZ-binding motif in growth factor regulation of Glut1 degradation and trafficking.

Journal Article Biochem J · March 1, 2009 Cell surface localization of the Glut (glucose transporter), Glut1, is a cytokine-controlled process essential to support the metabolism and survival of haemopoietic cells. Molecular mechanisms that regulate Glut1 trafficking, however, are not certain. In ... Full text Link to item Cite

Across the meiotic divide - CSF activity in the post-Emi2/XErp1 era.

Journal Article Journal of cell science · November 2008 Vertebrate eggs are arrested at the metaphase stage of meiosis II. Only upon fertilization will the metaphase-II-arrested eggs exit meiosis II and enter interphase. In 1971, Masui and Markert injected egg extracts into a two-cell-stage embryo and found tha ... Full text Open Access Cite

A gel-free MS-based quantitative proteomic approach accurately measures cytochrome P450 protein concentrations in human liver microsomes.

Journal Article Proteomics · October 2008 The human cytochrome P450 (P450) superfamily consists of membrane-bound proteins that metabolize a myriad of xenobiotics and endogenous compounds. Quantification of P450 expression in various tissues under normal and induced conditions has an important rol ... Full text Cite

Caspase cleavage is not for everyone.

Journal Article Cell · September 2008 During apoptosis, caspases cleave cellular substrates to break down and package the apoptotic cell for removal. Reporting in Cell, Mahrus et al. (2008) and Dix et al. (2008) use new approaches that identify hundreds of previously unrecognized caspase subst ... Full text Cite

Inhibition of apoptosome formation by suppression of Hsp90beta phosphorylation in tyrosine kinase-induced leukemias.

Journal Article Molecular and cellular biology · September 2008 Constitutively active tyrosine kinases promote leukemogenesis by increasing cell proliferation and inhibiting apoptosis. However, mechanisms underlying apoptotic inhibition have not been fully elucidated. In many settings, apoptosis occurs by mitochondrial ... Full text Cite

Cdc2 and Mos regulate Emi2 stability to promote the meiosis I-meiosis II transition.

Journal Article Molecular biology of the cell · August 2008 The transition of oocytes from meiosis I (MI) to meiosis II (MII) requires partial cyclin B degradation to allow MI exit without S phase entry. Rapid reaccumulation of cyclin B allows direct progression into MII, producing a cytostatic factor (CSF)-arreste ... Full text Cite

Aven-dependent activation of ATM following DNA damage.

Journal Article Curr Biol · July 8, 2008 BACKGROUND: In response to DNA damage, cells undergo either cell-cycle arrest or apoptosis, depending on the extent of damage and the cell's capacity for DNA repair. Cell-cycle arrest induced by double-stranded DNA breaks depends on activation of the ataxi ... Full text Link to item Cite

Not-so-pseudo a substrate: Acm1-mediated inhibition of the APC.

Journal Article Molecular cell · June 2008 In a recent issue of Molecular Cell, Enquist-Newman et al. (2008) demonstrate that Acm1 is ubiquitinated by APC(Cdc20). By contrast, the high-affinity interaction between Acm1 and APC(Cdh1) renders it a poor substrate, but a specific inhibitor, of the APC( ... Full text Cite

Mitochondrial localization of Reaper to promote inhibitors of apoptosis protein degradation conferred by GH3 domain-lipid interactions.

Journal Article J Biol Chem · January 4, 2008 Morphological hallmarks of apoptosis result from activation of the caspase family of cysteine proteases, which are opposed by a pro-survival family of inhibitors of apoptosis proteins (IAPs). In Drosophila, disruption of IAP function by Reaper, HID, and Gr ... Full text Link to item Cite

Differential Apaf-1 levels allow cytochrome c to induce apoptosis in brain tumors but not in normal neural tissues.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2007 Brain tumors are typically resistant to conventional chemotherapeutics, most of which initiate apoptosis upstream of mitochondrial cytochrome c release. In this study, we demonstrate that directly activating apoptosis downstream of the mitochondria, with c ... Full text Open Access Cite

Human enteric microsomal CYP4F enzymes O-demethylate the antiparasitic prodrug pafuramidine.

Journal Article Drug metabolism and disposition: the biological fate of chemicals · November 2007 CYP4F enzymes, including CYP4F2 and CYP4F3B, were recently shown to be the major enzymes catalyzing the initial oxidative O-demethylation of the antiparasitic prodrug pafuramidine (DB289) by human liver microsomes. As suggested by a low oral bioavailabilit ... Full text Cite

Control of Emi2 activity and stability through Mos-mediated recruitment of PP2A.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · October 2007 Before fertilization, vertebrate eggs are arrested in meiosis II by cytostatic factor (CSF), which holds the anaphase-promoting complex (APC) in an inactive state. It was recently reported that Mos, an integral component of CSF, acts in part by promoting t ... Full text Open Access Cite

Mcm10 and And-1/CTF4 recruit DNA polymerase alpha to chromatin for initiation of DNA replication.

Journal Article Genes & development · September 2007 The MCM2-7 helicase complex is loaded on DNA replication origins during the G1 phase of the cell cycle to license the origins for replication in S phase. How the initiator primase-polymerase complex, DNA polymerase alpha (pol alpha), is brought to the orig ... Full text Open Access Cite

Filling a GAP(DH) in caspase-independent cell death.

Journal Article Cell · June 2007 Mitochondrial outer-membrane permeabilization can lead to cell death even without activation of caspases. In this issue of Cell, Colell et al. (2007) identify the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase as a potent inhibitor of caspase-i ... Full text Cite

Cdc25 and Wee1: Analogous opposites?

Journal Article Cell Division · May 4, 2007 Movement through the cell cycle is controlled by the temporally and spatially ordered activation of cyclin-dependent kinases paired with their respective cyclin binding partners. Cell cycle events occur in a stepwise fashion and are monitored by molecular ... Full text Open Access Cite

HLA-B-associated transcript 3 (Bat3)/Scythe is essential for p300-mediated acetylation of p53.

Journal Article Genes & development · April 2007 In response to DNA damage, p53 undergoes post-translational modifications (including acetylation) that are critical for its transcriptional activity. However, the mechanism by which p53 acetylation is regulated is still unclear. Here, we describe an essent ... Full text Open Access Cite

A role for Cdc2- and PP2A-mediated regulation of Emi2 in the maintenance of CSF arrest.

Journal Article Current biology : CB · February 2007 BackgroundVertebrate oocytes are arrested in metaphase II of meiosis prior to fertilization by cytostatic factor (CSF). CSF enforces a cell-cycle arrest by inhibiting the anaphase-promoting complex (APC), an E3 ubiquitin ligase that targets Cyclin ... Full text Cite

Role for the PP2A/B56delta phosphatase in regulating 14-3-3 release from Cdc25 to control mitosis.

Journal Article Cell · November 17, 2006 DNA-responsive checkpoints prevent cell-cycle progression following DNA damage or replication inhibition. The mitotic activator Cdc25 is suppressed by checkpoints through inhibitory phosphorylation at Ser287 (Xenopus numbering) and docking of 14-3-3. Ser28 ... Full text Link to item Cite

Multifunctional reaper: sixty-five amino acids of fury.

Journal Article Cell death and differentiation · August 2006 Full text Cite

The apoptosome: physiological, developmental, and pathological modes of regulation.

Journal Article Developmental cell · May 2006 Apoptosis, a form of programmed cell death, is executed by a family of zymogenic proteases known as caspases, which cleave an array of intracellular substrates in the dying cell. Many proapoptotic stimuli trigger cytochrome c release from mitochondria, pro ... Full text Cite

A role for PP1 in the Cdc2/Cyclin B-mediated positive feedback activation of Cdc25.

Journal Article Mol Biol Cell · April 2006 The Cdc25 phosphatase promotes entry into mitosis through the removal of inhibitory phosphorylations on the Cdc2 subunit of the Cdc2/CyclinB complex. During interphase, or after DNA damage, Cdc25 is suppressed by phosphorylation at Ser287 (Xenopus numberin ... Full text Link to item Cite

Enhanced sensitivity to cytochrome c-induced apoptosis mediated by PHAPI in breast cancer cells.

Journal Article Cancer Res · February 15, 2006 Apoptotic signaling defects both promote tumorigenesis and confound chemotherapy. Typically, chemotherapeutics stimulate cytochrome c release to the cytoplasm, thereby activating the apoptosome. Although cancer cells can be refractory to cytochrome c relea ... Full text Link to item Cite

Direct ribosomal binding by a cellular inhibitor of translation.

Journal Article Nature structural & molecular biology · February 2006 During apoptosis and under conditions of cellular stress, several signaling pathways promote inhibition of cap-dependent translation while allowing continued translation of specific messenger RNAs encoding regulatory and stress-response proteins. We report ... Full text Cite

Analysis of the cell cycle using Xenopus egg extracts.

Journal Article Current protocols in cell biology · January 2006 In this unit, Xenopus eggs are isolated from hormonally primed female frogs, and then the extract is treated with cyclohexamide so it remains in interphase of the cell cycle. In the presence of sperm chromatin and ATP, membrane vesicles in the extract fuse ... Full text Cite

Study of apoptosis in vitro using the Xenopus egg extract reconstitution system.

Journal Article Methods in molecular biology (Clifton, N.J.) · January 2006 It was first shown by Newmeyer and colleagues in the 1990s that the molecular events of apoptosis could be reconstituted in vitro using Xenopus egg extracts. When the egg extract is allowed to incubate at room temperature for an extended time, the biochemi ... Full text Cite

Metabolic regulation of oocyte cell death through the CaMKII-mediated phosphorylation of caspase-2.

Journal Article Cell · October 2005 Vertebrate female reproduction is limited by the oocyte stockpiles acquired during embryonic development. These are gradually depleted over the organism's lifetime through the process of apoptosis. The timer that triggers this cell death is yet to be ident ... Full text Cite

Apoptosis in Drosophila: neither fish nor fowl (nor man, nor worm).

Journal Article Journal of cell science · May 2005 Studies in a wide variety of organisms have produced a general model for the induction of apoptosis in which multiple signaling pathways lead ultimately to activation of the caspase family of proteases. Once activated, these enzymes cleave key cellular sub ... Full text Open Access Cite

Inhibition of the anaphase-promoting complex by the Xnf7 ubiquitin ligase.

Journal Article The Journal of cell biology · April 2005 Degradation of specific protein substrates by the anaphase-promoting complex/cyclosome (APC) is critical for mitotic exit. We have identified the protein Xenopus nuclear factor 7 (Xnf7) as a novel APC inhibitor able to regulate the timing of exit from mito ... Full text Open Access Cite

DNA replication checkpoint control of Wee1 stability by vertebrate Hsl7.

Journal Article The Journal of cell biology · December 2004 G2/M checkpoints prevent mitotic entry upon DNA damage or replication inhibition by targeting the Cdc2 regulators Cdc25 and Wee1. Although Wee1 protein stability is regulated by DNA-responsive checkpoints, the vertebrate pathways controlling Wee1 degradati ... Full text Cite

Bcr-Abl-mediated protection from apoptosis downstream of mitochondrial cytochrome c release.

Journal Article Molecular and cellular biology · December 2004 Bcr-Abl, activated in chronic myelogenous leukemias, is a potent cell death inhibitor. Previous reports have shown that Bcr-Abl prevents apoptosis through inhibition of mitochondrial cytochrome c release. We report here that Bcr-Abl also inhibits caspase a ... Full text Cite

A dimerized coiled-coil domain and an adjoining part of geminin interact with two sites on Cdt1 for replication inhibition.

Journal Article Molecular cell · July 2004 Geminin is a cellular protein that associates with Cdt1 and inhibits Mcm2-7 loading during S phase. It prevents multiple cycles of replication per cell cycle and prevents episome replication. It also directly inhibits the HoxA11 transcription factor. Here ... Full text Cite

When the checkpoints have gone: insights into Cdc25 functional activation.

Journal Article Cell cycle (Georgetown, Tex.) · April 2004 DNA-responsive checkpoints operate at the G(2)/M transition to prevent premature mitosis in the presence of incompletely replicated or damaged DNA. These pathways prevent mitotic entry, at least in part, by suppressing Cdc25, the phosphatase that activates ... Cite

When the checkpoints have gone: Insights into Cdc25 functional activation

Journal Article Cell Cycle · January 1, 2004 DNA-responsive checkpoints operate at the G2/M transition to prevent premature mitosis in the presence of incompletely replicated or damaged DNA. These pathways prevent mitotic entry, at least in part, by suppressing Cdc25, the phosphatase that activates C ... Full text Cite

Cell division, growth and death. Cell growth: live and let die.

Journal Article Current opinion in cell biology · December 2003 Full text Cite

A GH3-like domain in reaper is required for mitochondrial localization and induction of IAP degradation.

Journal Article J Biol Chem · November 7, 2003 Reaper is a potent pro-apoptotic protein originally identified in a screen for Drosophila mutants defective in apoptotic induction. Multiple functions have been ascribed to this protein, including inhibition of IAPs (inhibitors of apoptosis); induction of ... Full text Link to item Cite

PP1 control of M phase entry exerted through 14-3-3-regulated Cdc25 dephosphorylation.

Journal Article EMBO J · November 3, 2003 It has been known for over a decade that inhibition of protein phosphatase 1 (PP1) activity prevents entry into M phase, but the relevant substrate has not been identified. We report here that PP1 is required for dephosphorylation of the Cdc2-directed phos ... Full text Link to item Cite

Inhibition of translation and induction of apoptosis by Bunyaviral nonstructural proteins bearing sequence similarity to reaper.

Journal Article Molecular biology of the cell · October 2003 Members of the California serogroup of bunyaviruses (family Bunyaviridae) are the leading cause of pediatric viral encephalitis in North America. Significant cell death is observed as part of the infection pathology. We now report that a Bunyaviral nonstru ... Full text Cite

Reaper is regulated by IAP-mediated ubiquitination.

Journal Article J Biol Chem · February 7, 2003 In most cases, apoptotic cell death culminates in the activation of the caspase family of cysteine proteases, leading to the orderly dismantling and elimination of the cell. The IAPs (inhibitors of apoptosis) comprise a family of proteins that oppose caspa ... Full text Link to item Cite

Phosphorylation of the cyclin b1 cytoplasmic retention sequence by mitogen-activated protein kinase and Plx.

Journal Article Molecular cancer research : MCR · February 2003 The cyclin B1/Cdc2 complex regulates many of the dramatic cellular rearrangements observed at mitosis. Although predominantly cytoplasmic during interphase, this kinase complex translocates precipitously to the nucleus at the G(2)-M transition. The interph ... Cite

Identification of the nuclear localization signal in Xenopus cyclin E and analysis of its role in replication and mitosis.

Journal Article Molecular biology of the cell · December 2002 Cyclin-dependent kinase (Cdk)2/cyclin E is imported into nuclei assembled in Xenopus egg extracts by a pathway that requires importin-alpha and -beta. Here, we identify a basic nuclear localization sequence (NLS) in the N-terminus of Xenopus cyclin E. Muta ... Full text Cite

Xnf7 and the regulation of Xenopus cyclin B2

Conference MOLECULAR BIOLOGY OF THE CELL · November 1, 2002 Link to item Cite

Reaper eliminates IAP proteins through stimulated IAP degradation and generalized translational inhibition.

Journal Article Nat Cell Biol · June 2002 Inhibitors of apoptosis (IAPs) inhibit caspases, thereby preventing proteolysis of apoptotic substrates. IAPs occlude the active sites of caspases to which they are bound and can function as ubiquitin ligases. IAPs are also reported to ubiquitinate themsel ... Full text Link to item Cite

Apoptotic regulation by the Crk adapter protein mediated by interactions with Wee1 and Crm1/exportin.

Journal Article Molecular and cellular biology · March 2002 The adapter protein Crk contains an SH2 domain and two SH3 domains. Through binding of particular ligands to the SH2 domain and the N-terminal SH3 domain, Crk has been implicated in a number of signaling processes, including regulation of cell growth, cell ... Full text Cite

Post-cytochrome C protection from apoptosis conferred by a MAPK pathway in Xenopus egg extracts.

Journal Article Molecular biology of the cell · February 2002 In response to many different apoptotic stimuli, cytochrome c is released from the intermembrane space of the mitochondria into the cytoplasm, where it serves as a cofactor in the activation of procaspase 9. Inhibition of this process can occur either by p ... Full text Cite

Analysis of apoptosis using Xenopus egg extracts.

Journal Article Current protocols in cell biology · May 2001 In the presence of a subcellular fraction enriched for mitochondria, after prolonged incubation the Xenopus egg extract can mimic biochemical aspects of apoptosis such as caspase activation, and DNA fragmentation. This unit describes preparation of an apop ... Full text Cite

Preparation and use of interphase Xenopus egg extracts.

Journal Article Current protocols in cell biology · May 2001 In this unit, Xenopus eggs are isolated from hormonally primed female frogs, and then the extract is treated with cyclohexamide so it remains in interphase of the cell cycle. In the presence of sperm chromatin and ATP, membrane vesicles in the extract fuse ... Full text Cite

Reversible inhibition of Hsp70 chaperone function by Scythe and Reaper.

Journal Article The EMBO journal · March 2001 Protein folding mediated by the Hsp70 family of molecular chaperones requires both ATP and the co-chaperone Hdj-1. BAG-1 was recently identified as a bcl-2-interacting, anti-apoptotic protein that binds to the ATPase domain of Hsp70 and prevents the releas ... Full text Cite

Mitochondria in apoptosis and human disease.

Journal Article Current molecular medicine · March 2001 Apoptosis is a process of cell suicide whereby individual cells are destroyed while preserving the integrity and architecture of surrounding tissue. This targeted cell destruction is critical both in physiological contexts as well as pathological states. I ... Full text Cite

Combinatorial control of cyclin B1 nuclear trafficking through phosphorylation at multiple sites.

Journal Article The Journal of biological chemistry · February 2001 Entry into mitosis is regulated by the Cdc2 kinase complexed to B-type cyclins. We and others recently reported that cyclin B1/Cdc2 complexes, which appear to be constitutively cytoplasmic during interphase, actually shuttle continually into and out of the ... Full text Cite

Wee1-regulated apoptosis mediated by the crk adaptor protein in Xenopus egg extracts.

Journal Article J Cell Biol · December 25, 2000 Many of the biochemical reactions of apoptotic cell death, including mitochondrial cytochrome c release and caspase activation, can be reconstituted in cell-free extracts derived from Xenopus eggs. In addition, because caspase activation does not occur unt ... Full text Open Access Link to item Cite

Requirement of the prolyl isomerase Pin1 for the replication checkpoint.

Journal Article Science · March 3, 2000 The peptidyl-prolyl isomerase Pin1 has been implicated in regulating cell cycle progression. Pin1 was found to be required for the DNA replication checkpoint in Xenopus laevis. Egg extracts depleted of Pin1 inappropriately transited from the G2 to the M ph ... Full text Link to item Cite

A family of ubiquitin-like proteins binds the ATPase domain of Hsp70-like Stch.

Journal Article FEBS letters · February 2000 We have isolated two human ubiquitin-like (UbL) proteins that bind to a short peptide within the ATPase domain of the Hsp70-like Stch protein. Chap1 is a duplicated homologue of the yeast Dsk2 gene that is required for transit through the G2/M phase of the ... Full text Cite

Reaper-induced dissociation of a Scythe-sequestered cytochrome c-releasing activity.

Journal Article The EMBO journal · October 1999 Reaper is a potent apoptotic inducer critical for programmed cell death in the fly Drosophila melanogaster. While Reaper homologs from other species have not yet been reported, ectopic expression of Reaper in cells of vertebrate origin can also trigger apo ... Full text Cite

Mitochondria at the crossroad of apoptotic cell death.

Journal Article Journal of bioenergetics and biomembranes · August 1999 In the past few years, it has become widely appreciated that apoptotic cell death generally involves activation of a family of proteases, the caspases, which undermine the integrity of the cell by cleavage of critical intracellular substrates. Caspases, wh ... Full text Cite

All aboard the cyclin train: subcellular trafficking of cyclins and their CDK partners.

Journal Article Trends in cell biology · June 1999 Progression through the cell cycle is governed by the periodic activation and inactivation of cyclin-dependent kinase complexes (CDK-cyclins). Although the enzymatic activity of these complexes is regulated tightly, it has recently been demonstrated that a ... Full text Cite

Maintenance of G2 arrest in the Xenopus oocyte: a role for 14-3-3-mediated inhibition of Cdc25 nuclear import.

Journal Article The EMBO journal · April 1999 Cdc2-cyclin B1 in the G2-arrested Xenopus oocyte is held inactive by phosphorylation of Cdc2 at two negative regulatory sites, Thr14 and Tyr15. Upon treatment with progesterone, these sites are dephosphorylated by the dual specificity phosphatase, Cdc25, l ... Full text Cite

Nuclear import of Cdk/cyclin complexes: identification of distinct mechanisms for import of Cdk2/cyclin E and Cdc2/cyclin B1.

Journal Article The Journal of cell biology · January 1999 Reversible phosphorylation of nuclear proteins is required for both DNA replication and entry into mitosis. Consequently, most cyclin-dependent kinase (Cdk)/cyclin complexes are localized to the nucleus when active. Although our understanding of nuclear tr ... Full text Open Access Cite

Regulation of apoptotic signaling pathways in cell-free extracts

Journal Article FASEB Journal · December 1, 1998 ApoptOBis is a program of cellular suicide which rids multicellular otanisms of damaged or extraneous cells. In order to elucidate the cellular signaling pathways which contribute to apoptotic cell death, we are utilizing an extract of Xenopus eggs which c ... Cite

Scythe: a novel reaper-binding apoptotic regulator.

Journal Article The EMBO journal · November 1998 Reaper is a central regulator of apoptosis in Drosophila melanogaster. With no obvious catalytic activity or homology to other known apoptotic regulators, reaper's mechanism of action has been obscure. We recently reported that recombinant Drosophila reape ... Full text Cite

The mitotic peptidyl-prolyl isomerase, Pin1, interacts with Cdc25 and Plx1.

Journal Article EMBO J · August 10, 1998 The cis/trans peptidyl-prolyl isomerase, Pin1, is a regulator of mitosis that is well conserved from yeast to man. Here we demonstrate that depletion of Pin1-binding proteins from Xenopus egg extracts results in hyperphosphorylation and inactivation of the ... Full text Link to item Cite

Control of cyclin B1 localization through regulated binding of the nuclear export factor CRM1.

Journal Article Genes & development · July 1998 Activation of the Cyclin B/Cdc2 kinase complex triggers entry into mitosis in all eukaryotic cells. Cyclin B1 localization changes dramatically during the cell cycle, precipitously transiting from the cytoplasm to the nucleus at the beginning of mitosis. P ... Full text Open Access Cite

Apoptosis induction by caspase-8 is amplified through the mitochondrial release of cytochrome c.

Journal Article The Journal of biological chemistry · June 1998 Apoptosis often involves the release of cytochrome c from mitochondria, leading to caspase activation. However, in apoptosis mediated by CD95 (Fas/APO-1), caspase-8 (FLICE/MACH/Mch5) is immediately activated and, in principle, could process other caspases ... Full text Cite

Negative regulation of DNA replication by the retinoblastoma protein is mediated by its association with MCM7.

Journal Article Molecular and cellular biology · May 1998 A yeast two-hybrid screen was employed to identify human proteins that specifically bind the amino-terminal 400 amino acids of the retinoblastoma (Rb) protein. Two independent cDNAs resulting from this screen were found to encode the carboxy-terminal 137 a ... Full text Cite

Regulation of apoptosis in Xenopus egg extracts.

Journal Article Advances in enzyme regulation · January 1998 Full text Cite

Reaper-induced apoptosis in a vertebrate system.

Journal Article The EMBO journal · December 1997 The reaper protein of Drosophila melanogaster has been shown to be a central regulator of apoptosis in that organism. However, it has not been shown to function in any vertebrate nor have the cellular components required for its action been defined. In thi ... Full text Cite

Crk is required for apoptosis in Xenopus egg extracts.

Journal Article The EMBO journal · January 1997 Apoptosis is essential for the development and homeostasis of multicellular organisms. Recently, a cell-free extract prepared from Xenopus eggs was shown to recapitulate intracellular apoptotic pathways in vitro. While many stimuli have been shown to trigg ... Full text Cite

Apoptosis in Xenopus egg extracts.

Journal Article Methods in enzymology · January 1997 Full text Cite

Regulatory roles of cyclin dependent kinase phosphorylation in cell cycle control.

Journal Article Curr Opin Cell Biol · December 1996 Cyclins and cyclin-dependent kinases (Cdks) are universal regulators of cell cycle progression in eukaryotic cells. Cdk activity is controlled by phosphorylation at three conserved sites, and many of the enzymes that act on these sites have now been identi ... Full text Link to item Cite

Cyclin-binding motifs are essential for the function of p21CIP1.

Journal Article Molecular and cellular biology · September 1996 The cyclin-dependent kinase (Cdk) inhibitor p21 is induced by the tumor suppressor p53 and is required for the G1-S block in cells with DNA damage. We report that there are two copies of a cyclin-binding motif in p21, Cy1 and Cy2, which interact with the c ... Full text Cite

Evidence for a dual role for TC4 protein in regulating nuclear structure and cell cycle progression.

Journal Article The Journal of cell biology · May 1994 TC4, a ras-like G protein, has been implicated in the feedback pathway linking the onset of mitosis to the completion of DNA replication. In this report we find distinct roles for TC4 in both nuclear assembly and cell cycle progression. Mutant and wild-typ ... Full text Cite

Membrane localization of the kinase which phosphorylates p34cdc2 on threonine 14.

Journal Article Molecular biology of the cell · March 1994 The key regulator of entry into mitosis is the serine/threonine kinase p34cdc2. This kinase is regulated both by association with cyclins and by phosphorylation at several sites. Phosphorylation at Tyr 15 and Thr 14 are believed to inhibit the kinase activ ... Full text Cite

RCC1, a regulator of mitosis, is essential for DNA replication.

Journal Article Molecular and cellular biology · August 1992 Temperature-sensitive mutants in the RCC1 gene of BHK cells fail to maintain a correct temporal order of the cell cycle and will prematurely condense their chromosomes and enter mitosis at the restrictive temperature without having completed S phase. We ha ... Full text Cite

In vitro cell cycle arrest induced by using artificial DNA templates.

Journal Article Molecular and cellular biology · July 1992 In cell extracts of Xenopus eggs which oscillate between S and M phases of the cell cycle, the onset of mitosis is blocked by the presence of incompletely replicated DNA. In this report, we show that several artificial DNA templates (M13 single-stranded DN ... Full text Cite

Characterization of the murine BEK fibroblast growth factor (FGF) receptor: activation by three members of the FGF family and requirement for heparin.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · April 1992 The bek gene encodes a member of the high-affinity fibroblast growth factor receptor family. The BEK/FGFR-2 receptor is a membrane-spanning tyrosine kinase with the typical features of FGF receptors. We have cloned a murine bek cDNA and expressed it in rec ... Full text Open Access Cite

DNA replication and progression through the cell cycle.

Journal Article Ciba Foundation symposium · January 1992 Somatic cells possess control mechanisms which monitor DNA replication and assure that it is complete before mitosis is initiated. We have been investigating these mechanisms in Xenopus egg extracts. Using in vitro cycling extracts, which spontaneously alt ... Full text Cite

Association of p62c-yes with polyomavirus middle T-antigen mutants correlates with transforming ability.

Journal Article Journal of virology · April 1990 A number of mutants of polyomavirus middle T antigen (MTag) were constructed into replication-competent avian retroviruses. To assess the ability of these MTag variants to transform and to associate with the avian p60c-src and p62c-yes proto-oncogene produ ... Full text Cite

Phosphatidylinositol kinase type I activity associates with various oncogene products.

Journal Article Oncogene research · January 1989 We have assayed immunoprecipitates of several oncogene products from retrovirally infected chicken embryo fibroblasts (CEF) for phosphatidylinositol (PI) kinase activity. Immunoprecipitates of P68gag-ros, P130gag-tps, P47gag-crk, polyoma middle T (mT)-p60c ... Cite

Novel tyrosine kinase identified by phosphotyrosine antibody screening of cDNA libraries.

Journal Article Molecular and cellular biology · December 1988 In an attempt to clone protein tyrosine kinases, antiphosphotyrosine antibodies were used to screen lambda gt11 cDNA expression libraries. By this method, a 2.5-kilobase cDNA encoding a novel tyrosine kinase was isolated from a mouse liver cDNA library. Th ... Full text Cite

Enzymatically inactive p60c-src mutant with altered ATP-binding site is fully phosphorylated in its carboxy-terminal regulatory region.

Journal Article Cell · September 1987 Cellular src protein, p60c-src, is phosphorylated on tyrosine 527 in chicken embryo fibroblasts, and this phosphorylation is implicated in suppressing the protein-tyrosine kinase activity and transforming potential of p60c-src. To determine whether tyrosin ... Full text Cite

Characterization of avian and viral p60src proteins expressed in yeast.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 1987 Avian and viral p60src proteins were expressed from a galactose-inducible promoter in the yeast Saccharomyces cerevisiae. Both the viral and cellular src proteins produced in yeast cells were myristoylated at their amino termini, as is the case for src pro ... Full text Cite

Association of the polyomavirus middle-T antigen with c-yes protein.

Journal Article Nature · January 1987 Expression of the middle-T antigen of polyomavirus is sufficient to induce transformation of fibroblasts in culture and tumour formation in whole animals. Middle-T can form a complex with the cellular src gene product (p60c-src) and can be phosphorylated b ... Full text Cite

Transformation of chicken embryo fibroblasts and tumor induction by the middle T antigen of polyomavirus carried in an avian retroviral vector.

Journal Article Molecular and cellular biology · May 1986 The middle T antigen of polyomavirus transformed primary chicken embryo fibroblasts when expressed from a replication-competent avian retrovirus. This in vitro-constructed retrovirus, SRMT1, is a variant of Rous sarcoma virus that encodes the middle T anti ... Full text Cite