Topic
Calpastatin
About: Calpastatin is a research topic. Over the lifetime, 1116 publications have been published within this topic receiving 39573 citations. The topic is also known as: BS-17 & PLACK.
Papers published on a yearly basis
Papers
More filters
[...]
TL;DR: How calpain activity is regulated in cells is still unclear, but the calpains ostensibly participate in a variety of cellular processes including remodeling of cytoskeletal/membrane attachments, different signal transduction pathways, and apoptosis.
Abstract: The calpain system originally comprised three molecules: two Ca2+-dependent proteases, mu-calpain and m-calpain, and a third polypeptide, calpastatin, whose only known function is to inhibit the two calpains. Both mu- and m-calpain are heterodimers containing an identical 28-kDa subunit and an 80-kDa subunit that shares 55-65% sequence homology between the two proteases. The crystallographic structure of m-calpain reveals six "domains" in the 80-kDa subunit: 1). a 19-amino acid NH2-terminal sequence; 2). and 3). two domains that constitute the active site, IIa and IIb; 4). domain III; 5). an 18-amino acid extended sequence linking domain III to domain IV; and 6). domain IV, which resembles the penta EF-hand family of polypeptides. The single calpastatin gene can produce eight or more calpastatin polypeptides ranging from 17 to 85 kDa by use of different promoters and alternative splicing events. The physiological significance of these different calpastatins is unclear, although all bind to three different places on the calpain molecule; binding to at least two of the sites is Ca2+ dependent. Since 1989, cDNA cloning has identified 12 additional mRNAs in mammals that encode polypeptides homologous to domains IIa and IIb of the 80-kDa subunit of mu- and m-calpain, and calpain-like mRNAs have been identified in other organisms. The molecules encoded by these mRNAs have not been isolated, so little is known about their properties. How calpain activity is regulated in cells is still unclear, but the calpains ostensibly participate in a variety of cellular processes including remodeling of cytoskeletal/membrane attachments, different signal transduction pathways, and apoptosis. Deregulated calpain activity following loss of Ca2+ homeostasis results in tissue damage in response to events such as myocardial infarcts, stroke, and brain trauma.
2,731 citations
TL;DR: Calpain inhibitors can protect against necrotic neuronal death and, to a lesser extent, apoptotic death and caspase inhibitors strongly suppress apoptotic neuronal death.
957 citations
TL;DR: This is the first report to the authors' knowledge suggesting a direct link between the early, excitotoxic, calcium-mediated activation of calpain after cerebral hypoxia-ischemia and the subsequent activation of caspase-3, thus representing a tentative pathway of “pathological apoptosis.”
432 citations
TL;DR: It is reported that p35 can be cleaved to p25 both in vitro and in vivo by calpain, suggesting a role of the cleavage in neuronal cell death.
395 citations
TL;DR: Ubiquitous distribution of Ca 2+ -dependent neutral protease and its specific inhibitor in various tissues and cells is described and a proposal is made to call the protease calpain and the inhibitor calpastatin, both as generic names.
358 citations