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)

Several detergents were investigated for their ability to increase activity of 2':3'-cyclic nucleotide 3'-phosphodiesterase in isolated myelin. The ability of Triton X-100 and Sulfobetaine DLH to solubilize the enzyme was also examined. Solubilization with Triton X-100 was only effective in the presence of salt, for example with NaCl 51% of the activity was solubilized. A single extraction with Sulfobetaine DLH yielded slightly more solubilized enzyme and did not require added salt. Both activation and solubilization of 2':3'-cyclic nucleotide 3'-phosphodiesterase appeared to be similarly dependent on detergent concentration, suggesting a common action of the detergent in the two processes. Myelin basic protein was solubilized more readily than the enzyme. In contrast with the enzyme in myelin, 2':3'-cyclic nucleotide 3'-phosphodiesterase activity in C6 cells was not increased in the presence of Triton X-100, and was partially solubilized by either Triton X-100 or NaCl alone. No myelin basic protein could be detected in C6 cells by radioimmunoassay.
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PMID:Detergent activation and solubilization of 2':3'-cyclic nucleotide 3'-phosphodiesterase from isolated myelin and c6 cells. 22 62

Purified virions of the large RNA viruses show 2',3'-cyclic nucleotide 3'-phosphohydrolase (3'-CNPase) activity. The 3'-CNPase activity is virion-associated and stimulated by their treatment with nonionic detergents. Cytopathic viruses such as influenza A2 (Singapore/57), NDV, and VSV showed the specific activity of a virion-associated 3'-CNPase equal to or lower than the specific activity of host cell enzyme. Retroviruses are an example of extreme relationship of 3'-CNPase to virion. With the AMV-BAI-A associated enzyme activity increased after Triton X-100 treatment ten times more than that associated with other viruses examined. The specific activity of virus-associated 3'-CNPase was 16-28 times higher than that in chick myeloblasts. BLV showed a very low enzyme activity. The correlation between the activity of cellular 3'-CNPase and virus yield showed that 3'-CNPase could belong to cellular factors influencing virus replication.
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PMID:Relationship of 2',3'-cyclic nucleotide 3'-phosphohydrolase activity of large enveloped RNA viruses to host cell activity. 168 73

Purified Newcastle disease virus (NDV) virions possess 2',3'-cyclic nucleotide 2'-phosphohydrolase (2'-CNPase) and 2',3'-cyclic nucleotide 3'-phosphohydrolase (3'-CNPase) activities. These enzyme activities cannot be removed from the virion even after extensive purification by chromatography on controlled-pore glass. In the intact virion, the 3'-CNPase activity was stimulated by Triton X-100, while the 2'-CNPase activity was partially inhibited. We have prepared the NDV subunits and have shown that 3'-CNPase was associated exclusively with the viral nucleocapsid. In contrast, the 2'-CNPase activity was associated with both the envelope as well as the nucleocapsid. A threshold amount of both enzyme activities was detected in viral M protein.
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PMID:Localization of 2',3'-decycling phosphodiesterases in the Newcastle disease virus virion. 198 76

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

Extraction of rat brain myelin in a buffer containing Triton X-100 yielded a soluble fraction and an insoluble residue that was enriched in cytoskeletal elements. Immunoblot analysis of the detergent-soluble fraction and the insoluble cytoskeletal residue showed that all of the tubulin and more than half of the actin were found within the cytoskeletal fraction. The distribution of myelin-specific proteins was also examined, and revealed that 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) I and most of the myelin basic proteins (MBPs) were equally distributed between both fractions. By contrast, the large MBP (21.5 kDa) and CNPase II (50 kDa) were observed to partition almost entirely with the cytoskeletal fraction. Proteolipid protein was found predominantly in the detergent-soluble fraction, as was DM-20 protein. Analysis of the cytoskeletal fraction by sucrose-density-gradient centrifugation demonstrated that a distinct subset of lipids was tightly bound to the cytoskeletal protein residue. The cytoskeleton-associated lipid was considerably enriched in cerebroside and sphingomyelin by comparison with total myelin lipids. These results indicate that a cytoskeletal matrix is associated with multilamellar myelin, and suggest that this structure may play a fundamental role in myelinogenesis.
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PMID:Characterization of a cytoskeletal matrix associated with myelin from rat brain. 276 98

The distribution of calcium-activated neutral proteinase (CANP) activity was examined in the subcellular fractions of quaking and control mouse brain. The CANP activity was determined in purified myelin, cytosol and pellet (P2, consisting of nuclei, mitochondria and microsomes) fractions using [14C]azocasein as substrate. The enzyme activity in quaking brain was 1.3-fold greater than control. Fifty-seven percent of the control brain activity was in purified myelin compared to only 7% in quaking myelin. The specific activity of the control purified myelin was 4-fold greater than homogenate while that of the quaking was two-fold greater. In contrast, 51% of the quaking brain activity was present in cytosol compared to only 18% in the control. Triton X-100 greatly increased the control brain activity (10-fold) while the quaking brain activity was increased by only 1.2-fold. The total calcium content in the quaking brain was greatly elevated (6-fold) compared to control. Approximately 30% of the brain 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) activity was in quaking myelin while 77% of the CNPase activity in control brain was in myelin. These results suggest that in quaking brain much of the CANP is not incorporated into the myelin membrane and remains cytosolic.
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PMID:Distribution of calcium-activated neutral proteinase activity in quaking mouse brain: a subcellular study. 282 58

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