Calpains are calcium-activated proteases that have biomedical and biotechnological potential. Their activity is tightly regulated by their endogenous inhibitor, calpastatin that binds to the enzyme only in the presence of calcium. Conventional approaches to purify calpain comprise multiple chromatographic steps, and are labor-intensive, leading to low yields. Here we report a new purification p...

Here we demonstrate that heat shock protein 90 (HSP90) interacts with calpain-1, but not with calpain-2, and forms a discrete complex in which the protease maintains its catalytic activity, although with a lower affinity for Ca2+. Equilibrium gel distribution experiments show that this complex is composed by an equal number of molecules of each protein partner. Moreover, in resting cells, cytos...

The inhibitory domains of calpastatin contain three highly conserved regions, A, B, and C, of which A and C bind calpain in a strictly Ca(2+)-dependent manner but have no inhibitory activity whereas region B inhibits calpain on its own. We synthesized the 19-mer oligopeptides corresponding to regions A and C of human calpastatin domain I and tested their effect on human erythrocyte mu-calpain a...

Mammalian cells contain several proteolytic systems to carry out the degradative processes and complex regulatory mechanisms to prevent excessive protein breakdown. Among these systems, the Ca2+-activated proteolytic system involves the cysteine proteases denoted calpains, and their inhibitor, calpastatin. Despite the rapid progress in molecular research on calpains and calpastatin, the physiol...

Data from purebred Brahman steers (N = 467) were used to study the association of single nucleotide polymorphisms (SNP) with carcass traits and measures of tenderness. Fall weaned calves were grazed and fed in a subtropical environment and then harvested for processing in a commercial facility. Carcass data were recorded 24 h postmortem. Muscle samples and primal ribs were obtained to measure c...

A cDNA encoding an endogenous inhibitor, termed calpastatin, for calcium-dependent cysteine protease (calpain, EC 3.4.22.17) was cloned by screening rabbit cDNA libraries with a synthetic oligodeoxynucleotide probe based on the partial amino acid sequence of the purified protein. The deduced amino acid sequence contains 718 amino acid residues (Mr, 76,964), and the mature protein corresponds to...

This study was to investigate the role of calpain in the apoptosis of pulmonary microvascular endothelial cells (PMEC) during septic plasma stimulation. Septic plasma was collected from endotoxemic mice. In cultured PMEC, incubation with septic plasma stimulated calpain activation, increased caspase-3 activity and induced apoptotic cell death. These effects of septic plasma were abrogated by kn...

Abstract To investigate the effects of maternal nutritional plane and selenium (Se) level on offspring muscle development in first parity ewes, Rambouillet ewes (n = 84) were stratified by BW randomized to receive diets formulated contain adequate Se (ASe) or high (HSe) initiated at breeding. On d 40 gestation, assigned randomly within treatments supply 60% (RES), 100% (CON), 140% (HI) NRC requ...

8-Hydroxyquinoline and derivatives exhibit multifunctional properties, including antioxidant, antineurodegenerative, anticancer, anti-inflammatory and antidiabetic activities. In biological systems, elevation of intracellular calcium can cause calpain activation, leading to cell death. Here, the effect of 8-hydroxyquinoline and derivatives (5-chloro-7-iodo-8-hydroxyquinoline or clioquinol and 8...