Disease relevance of CAST

• In ovine muscle, changes in the activity of the calcium dependent neutral proteinases (calpains I and II) and their specific inhibitor (calpastatin) accompany beta-agonist-induced hypertrophy [1].
• Increasing the amount of calpastatin in the incubations limited both the rate and extent of proteolysis of myofibrillar proteins and autolysis of mu-calpain [2].

High impact information on CAST

• To investigate the regulation of calpastatin gene expression, we isolated bovine heart calpastatin cDNAs and 5'-regions of the calpastatin gene [3].
• This "XL" region contains three potential PKA phosphorylation sites but shares no homology with other regions of calpastatin or with any known protein [3].
• Transient transfection assays demonstrated that sequence within 272 nucleotides upstream of transcription initiation of the calpastatin gene is sufficient to direct moderate level transcription [3].
• In contrast, calpastatin (an inhibitor of calpain) and leupeptin (an inhibitor of lysosome) failed to prevent the decreases of IRS-1 and IRS-2 levels caused by LiCl or SB216763 [4].
• Changes in calpain and calpastatin mRNA induced by beta-adrenergic stimulation of bovine skeletal muscle [1].

Chemical compound and disease context of CAST

• Calpastatin, leupeptin, and E-64 did not inhibit the initial step of autolysis, but they did inhibit further breakdown of these fragments [5].

Biological context of CAST

• Nucleotide sequence analysis of the cDNA for bovine calpastatin revealed an average nucleotide sequence identity of approximately 70 to 80% compared with published calpastatin nucleotide sequences of human, rabbit, and pig [6].
• Short commuunication: Effect of dietary protein depletion and repletion on skeletal muscle calpastatin during early lactation [7].
• Exon 3, corresponding to a highly conserved 22-amino acid region, was deleted from bovine calpastatin domain L [6].
• Amino acid sequence analysis indicated that the phospholipid-binding fragment was derived from the amino terminus of the large calpastatin [8].
• Rapid communication: a TaqI restriction fragment length polymorphism in the bovine calpastatin gene [9].

Anatomical context of CAST

• Large forms of calpastatin from canine myocardium and rabbit liver also were bound to phosphatidylinositol [8].
• The binding of large calpastatin to biologic membranes is mediated in part by interaction of an amino terminal region with acidic phospholipids [8].
• Previously, myocardial calpastatin was shown to be present in preparations of sarcoplasmic reticulum and sarcolemma [8].
• Longissimus muscle samples were obtained for determining myofibril fragmentation index, Warner-Bratzler shear force, and sensory panel evaluation at 1, 7, and 14 d postmortem, and mu- and m-calpain and calpastatin activities at 24 h postmortem [10].
• Other traits were analyzed to determine their associations with mu- and m-calpain activity and MFI, including calpastatin activity, percentage of raw and cooked lipids, Warner-Bratzler shear force (WBSF) values after 7, 14, and 21 d of aging, and sensory panel rating of tenderness, juiciness, and connective tissue amount after 14 d of aging [11].

Associations of CAST with chemical compounds

• The activity of both calpain isoforms and calpastatin was measured in bovine longissimus dorsi samples from trials in which test animals were treated with the beta agonist cimaterol [1].
• In the present work, we show that purified bovine myocardial calpastatin binds to the acidic phospholipids, phosphatidylinositol and phosphatidylserine, but not to the neutral phospholipids, phosphatidylcholine and phosphatidylethanolamine [8].
• Freezing and calcium chloride marination effects on beef tenderness and calpastatin activity [12].

Other interactions of CAST

• Single nucleotide polymorphisms (SNPs) in the calpain 1 (CAPN1) and calpastatin (CAST) genes were studied to determine their effects on meat tenderness in Bos taurus cattle [13].

Analytical, diagnostic and therapeutic context of CAST

• Calpain and calpastatin contents of muscle taken at biopsy were evaluated using Western blotting techniques [7].
• The calculated molecular weight of bovine skeletal muscle calpastatin of 706 amino acid residues (M(r) 75,842) corresponds to the value of purified bovine skeletal muscle calpastatin as determined by SDS-PAGE (M(r) 68,000) [6].
• Northern blot analysis revealed the presence of multiple calpastatin mRNA transcripts having estimated sizes of 3.8, 3.0, and 1.5 kb in beef and 3.8, 3.0, 2.5, and 1.5 kb in sheep [6].
• Bovine skeletal muscle calpastatin: cloning, sequence analysis, and steady-state mRNA expression [6].
• Activities of mu- and m-calpain were not affected (P > .05) by castration; however, calpastatin was higher (P < .05) in muscles from the bull carcasses [10].

References