Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1389183 (autodigestion)
 317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There are two types of calcium-activated neutral protease (CANP), m-CANP and mu-CANP, following the nomenclature of Suzuki et al to show that each requires mM and microM Ca2+, respectively, for its activation. We found mu-CANP activity in a crude CANP fraction extracted from the peripheral nerve, which degraded the neurofilament (Nf) triplet (200 K, 160 K, 68 K), especially the 160 K component, at Ca2+ concentrations of 50 microM and 0.1 mM. The triplet was degraded in the order of the 160 K, 68 K, and 200 K components, respectively. In addition, the effects of partially purified mu-CANP of rabbit skeletal muscle, purified natural mu-CANP of bovine liver, derived mu-CANP prepared by autodigestion of chicken muscle m-CANP, m-CANP of chicken skeletal muscle, and cathepsin B of rat liver on the Nf were examined. Among the triplet components, the 160 K component was most rapidly degraded by all proteases so far tested. The difference in the effect of mu-CANP and m-CANP or cathepsin B on susceptibility of the 200 K component to degradation might be due to the difference of the relative amounts of enzymes to Nf.
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PMID:Calcium-activated neutral protease in the peripheral nerve, which requires microM order Ca2+, and its effect on the neurofilament triplet. 298 90

Some endogenous substrates were incubated with two forms of calcium-activated neutral protease (CANP) with high (muCANP) and low (mCANP) sensitivities to calcium ions. In addition to analyses of the processes of their degradation, changes in the molecular properties of these CANPs were also examined. Among the tested substrate proteins, the myosin heavy chain of rabbit skeletal muscle myofibrils and spectrin or band 3 protein of human erythrocyte membranes were degraded relatively rapidly. So far as these proteins were concerned, a higher degradation velocity was observed for muCANP than for mCANP. Vimentin from ascites tumor cells was degraded most rapidly and no difference was observed in degradation velocity between muCANP and mCANP. In all cases, muCANP and mCANP produced different proteolytic peptide fragments, suggesting the different substrate-specificities of these CANPs. The degradation of substrates always accompanied the autodigestion of CANPs, and the small subunits of both CANPs were degraded in the early stage of the autodigestion. The large subunit of muCANP (79K) was converted to a 76K polypeptide via a 77K polypeptide as an intermediate. The autodigested muCANP with 76K polypeptide retained sufficient protease activity and, moreover, its calcium-sensitivity was higher than that of intact muCANP. The possibility is thus proposed that restricted autodigestion is a necessary activation step for the appearance of activity of muCANP. No such transition was observed for mCANP.
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PMID:Hydrolytic and autolytic behavior of two forms of calcium-activated neutral protease (CANP). 299 95