A study of the induction of cell division in amphibian oocytes by insulin☆
[摘要] RipeXenopusoocytes,1.4mmindiameter,arrestedinprophaseofmeiosisIundergomeioticcelldivisioninvitrouponexposuretoinsulin.Theroleofinsulinbindinginmediatingtheresponseoftheoocytehasbeeninvestigated.ScatchardanalysisofspecificinsulinbindingtooocytesrevealedcurvilinearkineticswithaKDof1.4nMand4×107receptorsperoocyteforthehigh-affinitycomponent.However,theEC50forinductionofcelldivisionbyinsulinwas12nMinthepresenceof10mg/mlbovineserumalbumin.OocytestreatedwithPronasetoremoveallresidualfolliclecellsstillrespondedtosodiuminsulin,indicatinginductionoccurredattheleveloftheoocyte.Usinghighlevelsofhumananti-insulinreceptorantibody,whichwasdemonstratedtobindspecificallytotheoocyte,50%ofspecificinsulinbindingwasprevented.Undertheseconditions,neitherthedose-responsecurveforinductionofcelldivisionbyinsulinnorthetimecoursewaschangedbythepresenceofantireceptorantibody.Otherstudiesdemonstratethatpureinsulin-likegrowthfactorcaninducecelldivisioninoocytes.Theseresultsindicatethattheinductionofcelldivisioninamphibianoocytesbyinsulinisnotmediatedbythehigh-affinitycomponentofinsulinbindingandmayinvolveinteractionofinsulinwithinsulin-likegrowthfactorreceptors.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
