Author
William C. Earnshaw
Other affiliations: University of Calgary, Mayo Clinic, Wellcome Trust ...read more
Bio: William C. Earnshaw is an academic researcher from University of Edinburgh. The author has contributed to research in topics: Centromere & Mitosis. The author has an hindex of 115, co-authored 371 publications receiving 51319 citations. Previous affiliations of William C. Earnshaw include University of Calgary & Mayo Clinic.
Topics: Centromere, Mitosis, Kinetochore, Chromatin, Aurora B kinase
Papers published on a yearly basis
Papers
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01 Jan 1999
TL;DR: Caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases as discussed by the authors, and they play critical roles in initiation and execution of this process.
Abstract: ■ Abstract Apoptosis is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli. Studies performed over the past 10 years have demonstrated that proteases play critical roles in initiation and execution of this process. The caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases. Caspases are synthesized as relatively inactive zymogens that become activated by scaffold-mediated transactivation or by cleavage via upstream proteases in an intracellular cascade. Regulation of caspase activation and activity occurs at several different levels: ( a) Zymogen gene transcription is regulated; ( b) antiapoptotic members of the Bcl-2 family and other cellular polypeptides block proximity-induced activation of certain procaspases; and ( c) certain cellular inhibitor of apoptosis proteins (cIAPs) can bind to and inhibit active caspases. Once activated, caspases cleave a variety of intracellular polypeptides, including major structural elements of the cytoplasm and nucleus, components of the DNA repair machinery, and a number of protein kinases. Collectively, these scissions disrupt survival pathways and disassemble important architectural components of the cell, contributing to the stereotypic morphological and biochemical changes that characterize apoptotic cell death.
2,685 citations
TL;DR: This work has shown that apoptotic cell death is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli, and that proteases play critical roles in initiation and execution of this process.
Abstract: ▪ Abstract Apoptosis is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli. Studies performed over the past 10 years have demonstrated that proteases play critical roles in initiation and execution of this process. The caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases. Caspases are synthesized as relatively inactive zymogens that become activated by scaffold-mediated transactivation or by cleavage via upstream proteases in an intracellular cascade. Regulation of caspase activation and activity occurs at several different levels: (a) Zymogen gene transcription is regulated; (b) antiapoptotic members of the Bcl-2 family and other cellular polypeptides block proximity-induced activation of certain procaspases; and (c) certain cellular inhibitor of apoptosis proteins (cIAPs) can bind to and inhibit active caspases. Once activated, caspases cleave a variet...
2,636 citations
TL;DR: A novel protease resembling ICE (prICE) that is active in a cell-free system that reproduces the morphological and biochemical events of apoptosis in the extracts including morphological changes, cleavage of PARP and production of an oligonucleosomal ladder.
Abstract: Recent studies suggest that proteases of the interleukin 1-beta-converting enzyme (ICE)/ced-3 family are involved in initiating the active phase of apoptosis. Here we identify a novel protease resembling ICE (prICE) that is active in a cell-free system that reproduces the morphological and biochemical events of apoptosis. prICE cleaves the nuclear enzyme poly(ADP-ribose) polymerase (PARP) at a tetrapeptide sequence identical to one of two ICE sites in pro-interleukin-1-beta. However, prICE does not cleave purified pro-interleukin-1-beta, and purified ICE does not cleave PARP, indicating that the two activities are distinct. Inhibition of prICE abolishes all manifestations of apoptosis in the extracts including morphological changes, cleavage of PARP and production of an oligonucleosomal ladder. These studies suggest that prICE might be pivotal in initiating the active phase of apoptosis in vitro and in intact cells.
2,631 citations
TL;DR: The two prototypic death pathways are described, current understanding of the role of the two pathways in chemotherapy-induced apoptosis is summarized, and the implications of these studies for mechanisms of resistance to chemotherapeutic agents are discussed.
1,226 citations
TL;DR: Aurora kinases regulate the structure and function of the cytoskeleton and chromosomes and the interactions between these two at the kinetochore during mitosis and regulate signalling by the spindle-assembly checkpoint pathway and cytokinesis.
Abstract: Aurora is the name given to a family of highly conserved protein kinases with essential roles in
many aspects of cell division. Yeasts have a single Aurora kinase, whereas mammals have three:
Aurora A, B and C. During mitosis, Aurora kinases regulate the structure and function of the cytoskeleton and chromosomes and the interactions between these two at the kinetochore.
They also regulate signalling by the spindle-assembly checkpoint pathway and cytokinesis.
Perturbation of Aurora kinase expression or function might lead to cancer.
1,135 citations
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28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations
TL;DR: The goal of this review is to provide a general overview of current knowledge on the process of apoptosis including morphology, biochemistry, the role of apoptoses in health and disease, detection methods, as well as a discussion of potential alternative forms of apoptotic proteins.
Abstract: The process of programmed cell death, or apoptosis, is generally characterized by distinct morphological characteristics and energy-dependent biochemical mechanisms. Apoptosis is considered a vital component of various processes including normal cell turnover, proper development and functioning of the immune system, hormone-dependent atrophy, embryonic development and chemical-induced cell death. Inappropriate apoptosis (either too little or too much) is a factor in many human conditions including neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer. The ability to modulate the life or death of a cell is recognized for its immense therapeutic potential. Therefore, research continues to focus on the elucidation and analysis of the cell cycle machinery and signaling pathways that control cell cycle arrest and apoptosis. To that end, the field of apoptosis research has been moving forward at an alarmingly rapid rate. Although many of the key apoptotic proteins have been identified, the molecular mechanisms of action or inaction of these proteins remain to be elucidated. The goal of this review is to provide a general overview of current knowledge on the process of apoptosis including morphology, biochemistry, the role of apoptosis in health and disease, detection methods, as well as a discussion of potential alternative forms of apoptosis.
10,744 citations
TL;DR: The basic components of the death machinery are reviewed, how they interact to regulate apoptosis in a coordinated manner is described, and the main pathways that are used to activate cell death are discussed.
Abstract: Apoptosis - the regulated destruction of a cell - is a complicated process. The decision to die cannot be taken lightly, and the activity of many genes influence a cell's likelihood of activating its self-destruction programme. Once the decision is taken, proper execution of the apoptotic programme requires the coordinated activation and execution of multiple subprogrammes. Here I review the basic components of the death machinery, describe how they interact to regulate apoptosis in a coordinated manner, and discuss the main pathways that are used to activate cell death.
7,255 citations
TL;DR: Mutation of the active site of caspase-9 attenuated the activation of cazase-3 and cellular apoptotic response in vivo, indicating that casp enzyme-9 is the most upstream member of the apoptotic protease cascade that is triggered by cytochrome c and dATP.
7,231 citations
TL;DR: This work has shown that understanding caspase regulation is intimately linked to the ability to rationally manipulate apoptosis for therapeutic gain.
Abstract: Apoptosis, an evolutionarily conserved form of cell suicide, requires specialized machinery. The central component of this machinery is a proteolytic system involving a family of proteases called caspases. These enzymes participate in a cascade that is triggered in response to proapoptotic signals and culminates in cleavage of a set of proteins, resulting in disassembly of the cell. Understanding caspase regulation is intimately linked to the ability to rationally manipulate apoptosis for therapeutic gain.
6,924 citations