{"title":"胰岛素分泌颗粒的蛋白质加工内肽酶。","authors":"E M Bailyes, D L Bennett, J C Hutton","doi":"10.1159/000468903","DOIUrl":null,"url":null,"abstract":"<p><p>Enzymological studies have implicated two Ca2+ dependent endopeptidases in the conversion of proinsulin to insulin: a type 1 activity and a type 2 activity which cleave on the C-terminal side of R31R32 and K64R65 in proinsulin, respectively. These activities were further characterized and their relationship to the mammalian family of subtilisin-like proteases was investigated. PC2 was expressed in neuroendocrine tissues and in insulinoma secretory granule fractions predominantly as a 65kDa protein. On anion-exchange chromatography of solubilized granules, PC1/3 immunoreactivity comigrated with a peak of type 1 activity whereas PC2 immunoreactivity coeluted with the peak of type 2 endopeptidase activity. PC2 antiserum gave a specific immunoprecipitation of type 2 activity from insulin granule extracts. It was concluded that the PC2 gene-product has type 2 endopeptidase activity.</p>","PeriodicalId":11933,"journal":{"name":"Enzyme","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000468903","citationCount":"34","resultStr":"{\"title\":\"Proprotein-processing endopeptidases of the insulin secretory granule.\",\"authors\":\"E M Bailyes, D L Bennett, J C Hutton\",\"doi\":\"10.1159/000468903\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Enzymological studies have implicated two Ca2+ dependent endopeptidases in the conversion of proinsulin to insulin: a type 1 activity and a type 2 activity which cleave on the C-terminal side of R31R32 and K64R65 in proinsulin, respectively. These activities were further characterized and their relationship to the mammalian family of subtilisin-like proteases was investigated. PC2 was expressed in neuroendocrine tissues and in insulinoma secretory granule fractions predominantly as a 65kDa protein. On anion-exchange chromatography of solubilized granules, PC1/3 immunoreactivity comigrated with a peak of type 1 activity whereas PC2 immunoreactivity coeluted with the peak of type 2 endopeptidase activity. PC2 antiserum gave a specific immunoprecipitation of type 2 activity from insulin granule extracts. It was concluded that the PC2 gene-product has type 2 endopeptidase activity.</p>\",\"PeriodicalId\":11933,\"journal\":{\"name\":\"Enzyme\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1991-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1159/000468903\",\"citationCount\":\"34\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Enzyme\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1159/000468903\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Enzyme","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1159/000468903","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Proprotein-processing endopeptidases of the insulin secretory granule.
Enzymological studies have implicated two Ca2+ dependent endopeptidases in the conversion of proinsulin to insulin: a type 1 activity and a type 2 activity which cleave on the C-terminal side of R31R32 and K64R65 in proinsulin, respectively. These activities were further characterized and their relationship to the mammalian family of subtilisin-like proteases was investigated. PC2 was expressed in neuroendocrine tissues and in insulinoma secretory granule fractions predominantly as a 65kDa protein. On anion-exchange chromatography of solubilized granules, PC1/3 immunoreactivity comigrated with a peak of type 1 activity whereas PC2 immunoreactivity coeluted with the peak of type 2 endopeptidase activity. PC2 antiserum gave a specific immunoprecipitation of type 2 activity from insulin granule extracts. It was concluded that the PC2 gene-product has type 2 endopeptidase activity.