{"title":"百日咳毒素对牛棒细胞膜上鸟嘌呤核苷酸交换的抑制作用。","authors":"V O Rybin, A A Gureeva, V A Tkachuk","doi":"10.3109/09687688909082265","DOIUrl":null,"url":null,"abstract":"<p><p>The effect of pertussis toxin on GTP-binding protein of bovine rod cell outer segments (transducin) was studied. Pertussis toxin was shown to ADP ribosylate either alpha subunit of free transducin or transducin-GDP complex, whereas GTP and its analogue Gpp(NH)p strongly inhibit ADP ribosylation of transducin. Pertussis toxin inhibits rod outer segment membrane GTPase and GTPase of homogeneous transducin by 40% and 70-80%, respectively. Activation of rod cell cyclic nucleotide phosphodiesterase by transducin is reduced after its preincubation with pertussis toxin. In transducin modified by pertussis toxin, 83% of GDP becomes tightly bound and cannot be exchanged with Gpp(NH)p. The stabilization of complex transducin-GDP after ADP ribosylation can explain the inhibitory effect of pertussis toxin on GTP hydrolysis by transducin, and on phosphodiesterase activation by guanyl nucleotides.</p>","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"8 2","pages":"115-26"},"PeriodicalIF":0.0000,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687688909082265","citationCount":"1","resultStr":"{\"title\":\"Inhibition by pertussis toxin of guanyl nucleotides exchange on transducin in bovine rod cell membranes.\",\"authors\":\"V O Rybin, A A Gureeva, V A Tkachuk\",\"doi\":\"10.3109/09687688909082265\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>The effect of pertussis toxin on GTP-binding protein of bovine rod cell outer segments (transducin) was studied. Pertussis toxin was shown to ADP ribosylate either alpha subunit of free transducin or transducin-GDP complex, whereas GTP and its analogue Gpp(NH)p strongly inhibit ADP ribosylation of transducin. Pertussis toxin inhibits rod outer segment membrane GTPase and GTPase of homogeneous transducin by 40% and 70-80%, respectively. Activation of rod cell cyclic nucleotide phosphodiesterase by transducin is reduced after its preincubation with pertussis toxin. In transducin modified by pertussis toxin, 83% of GDP becomes tightly bound and cannot be exchanged with Gpp(NH)p. The stabilization of complex transducin-GDP after ADP ribosylation can explain the inhibitory effect of pertussis toxin on GTP hydrolysis by transducin, and on phosphodiesterase activation by guanyl nucleotides.</p>\",\"PeriodicalId\":18448,\"journal\":{\"name\":\"Membrane biochemistry\",\"volume\":\"8 2\",\"pages\":\"115-26\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1989-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.3109/09687688909082265\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Membrane biochemistry\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3109/09687688909082265\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Membrane biochemistry","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3109/09687688909082265","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Inhibition by pertussis toxin of guanyl nucleotides exchange on transducin in bovine rod cell membranes.
The effect of pertussis toxin on GTP-binding protein of bovine rod cell outer segments (transducin) was studied. Pertussis toxin was shown to ADP ribosylate either alpha subunit of free transducin or transducin-GDP complex, whereas GTP and its analogue Gpp(NH)p strongly inhibit ADP ribosylation of transducin. Pertussis toxin inhibits rod outer segment membrane GTPase and GTPase of homogeneous transducin by 40% and 70-80%, respectively. Activation of rod cell cyclic nucleotide phosphodiesterase by transducin is reduced after its preincubation with pertussis toxin. In transducin modified by pertussis toxin, 83% of GDP becomes tightly bound and cannot be exchanged with Gpp(NH)p. The stabilization of complex transducin-GDP after ADP ribosylation can explain the inhibitory effect of pertussis toxin on GTP hydrolysis by transducin, and on phosphodiesterase activation by guanyl nucleotides.