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Related to calpain: cathepsin, calpastatin


A proteolytic enzyme regulated by the concentration of calcium ions.

[Probably cal(cium) + p(rote)a(se) + -in.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


any of various enzymes in mammals and other organisms that are involved in the proteolysis of endogenous proteins and are regulated by the concentration of calcium ions
[C20: from cal(modulin) + (pa)pain]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Calpain and cathepsin activities in postmortem fish and meat muscles.
- South San Francisco, California-based anti-fibrotic therapies specialist Blade Therapeuticshas initiated a Phase 1 clinical trial for its lead compound, BLD-2660, a selective small molecule dimeric calpain inhibitor, the company said.
By generating potent inhibitors to Calpain, Phelix is able to block the generation of myofibroblasts, the critical cell type in fibrosis.
Eklund, "Bcr-abl regulates Stat 5 through Shp2, the interferon consensus sequence binding protein (Icsbp/Irf8), growth arrest specific 2 (Gas2) and calpain," Oncotarget, vol.
Greer, "Ubiquitous calpains promote caspase-12 and JNK activation during endoplasmic reticulum stress-induced apoptosis," The Journal of Biological Chemistry, vol.
Long-lasting Ca2+ elevations activate calpain proteases, which further degrade proteins that participate in Ca2+ homeostasis and thereby aggravate myoplasmic Ca2+ overload.
Ishiguro, "[Ca.sup.2+]-induced release of mitochondrial m-calpain from outer membrane with binding of calpain small subunit and Grp75," Archives of Biochemistry and Biophysics, vol.