Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.37 (CNPase)
 539 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Calcium-activated neutral proteinase (CANP) activity was determined in subcellular fractions and in different regions of bovine brain. The CANP specific activity in spinal cord and corpus callosum, areas rich in myelin, were almost six-fold greater than cerebral cortex and cerebellum. Treatment of whole homogenate and myelin with 0.1% Triton X-100 increased the CANP activity by tenfold. Subcellular fractions were prepared from bovine brain gray and white matter. Most of the CANP activity (70%) was in the primary particulate fractions P1 (nuclear), P2 (mitochondrial) and P3 (microsomal). On subfractionation of each particulate fraction, the majority of the activity (greater than 50%) was recovered in the myelin-enriched fractions (P1A, P2A, P3A) which separate at the interphase of 0.32 M- and 0.85 M-sucrose. The distribution of activity was P2A greater than P1A greater than P3A. Further purification of myelin (of P2A) increased the specific activity over homogenate by more than three-fold. The same myelin fractions contained the highest proportion (60%) and specific activity (five-fold increase) of CNPase. The enzyme activity in different regions of brain and in subcellular fractions was increased by 20-39% after the inhibitor was removed. Electron microscopic study confirmed that the myelin fractions were highly purified. The cytosolic fraction contained 20-30% of the total homogenate CANP activity. Other fractions contained low enzyme activity. CANP was identified in the purified myelin fraction by electroimmublot-technique. It is concluded that the bulk of CANP in CNS is tightly bound to the membrane, may be masked or hidden and is intimately associated with the myelin sheath.
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PMID:The regional and subcellular distribution of calcium activated neutral proteinase (CANP) in the bovine central nervous system. 254 23

The activity of calcium-activated neutral proteinase (mM CANP) was determined in subcellular fractions of rat brain. The CANP activity in whole homogenate and its membrane fractions including myelin was increased ten-fold following treatment with Triton X-100. The majority of the activity (60%) was in the primary particulate fractions P1 (nuclear), P2 (mitochondrial), and P3 (microsomal). Following subfractionation of each particulate fraction, most of the activity (50%) was found in the myelin-enriched fractions (P1A, P2A, and P3A) and separated at the interface of 0.32-0.85 M sucrose. Only 20-30% of the total homogenate activity was in cytosol. The enrichment in the myelin fractions resembled that for 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) activity. Immunoblotting revealed that the CANP was mainly in myelin and cytosol. In addition to the presence of 72-76 Kd and 80 Kd bands, there were faint high-molecular-weight CANP bands ranging from 110-150 Kd and lower-molecular-weight forms in the region of 30-50 Kd in both purified myelin and cytosol. These studies suggested that CANP is present in myelin and cytosol and that it exists in the brain in membrane-bound and soluble forms.
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PMID:Calcium-activated neutral proteinase in rat brain myelin and subcellular fractions. 285 61

Peripheral nerves of the shiverer mouse, which are characterized by the absence of major dense lines and myelin basic proteins in CNS myelin, were analyzed. From subcellular fractionation of sciatic nerves, it was found from the SDS-polyacrylamide gel electrophoresis that the Pl and Pr proteins equivalent to myelin basic protein of CNS and PM protein were missing in the shiverer in both P2A and P3A fractions in which PNS myelin is recovered. No extra bands were observed in any other fractions of the shiverer in place of the absence of the proteins. The activities of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) of P2A and P3A fractions were high, but that of the P3X fraction which floated over 0.32 M sucrose was the highest among the fractions examined in both the shiverer and the control. Developmental analysis of the protein profiles revealed that PO, Pl, Pr and PM proteins increased rapidly from the sixth day postnatally up to the twentieth day after birth in the control. No differences were observed between the shiverer and the control as for PO protein, but Pl, Pr and PM proteins were absent in the shiverer throughout the development. The CNPase activity of total homogenate of sciatic nerve fibers at birth in the control showed high activity comparable to that of the adult value, but there was no significant difference in activity between the control and the shiverer at any stage of development. Immunohistochemical reaction using peroxidase anti-peroxidase method showed that the myelin from the shiverer did not react with the MBP antiserum, while that of the control reacted positively. On the contrary, the myelin from both shiverer and the control reacted positively against P2 antibody.
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PMID:Peripheral nervous system of shiverer mutant mice: developmental change of myelin components and immunohistochemical demonstration of the absence of MBP and presence of P2 protein. 618 16

Shiverer is an autosomal recessive mutant characterized by dysmyelination in the central nervous system. The myelin in the shiverer is devoid of the major dense line. The pattern of increase of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) in the various parts of central nervous system during postnatal development was identical with that of controls. Subcellular fractionation of the brain from shiverer showed that the recovery of CNPase activity of the P2A was only 14% of the control, but those of P2B and P3 were several times higher than the controls. The specificity activity of CNPase of the purified myelin and P2A from shiverer did not differ significantly from that of the controls. The combined P2 and P3 (P2 + P3) fraction was subjected to linear sucrose density gradient (0.32--1.3 M) centrifugation. By measuring CNPase activities of the fractions obtained after centrifugation, shiverer showed two peaks of CNPase activities in the sucrose gradient, although that of the control showed a single peak. The main peak obtained from shiverer was found in the region of higher sucrose concentration than that of the control, while a small peak was found in the region of lower sucrose concentration.
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PMID:Subcellular distribution and developmental change of 2',3'-cyclic nucleotide 3'-phosphohydrolase in the central nervous system of the myelin-deficient shiverer mutant mice. 625 87