The follicle cells are a major site of vitellogenin synthesis in Drosophila melanogaster☆
[摘要] Pulselabelingofproteins,invivo,followedbyindirectimmunoprecipitationofthevitellogeninpolypeptides,hasshownthatnotonlythethoracicandabdominalfatbodiesbutalsotheovarydevoteasignificantpercentageoftheirsyntheticcapacitytovitellogenin(VG)production.Thesemethodshavealsoshownthatovarianstages9and10contributethemajorityofVGsynthesizedbytheovaryandthatthefollicularepitheliumofthesestagesisthespecificsiteofVGsynthesis.Insituhybridization(ofaprobecontainingthecodingregionsofthetwolargerpolypeptides)tosectionsofovariesconfirmedthattheVGmRNAsareabundantspeciesinthecytoplasmofstage9and10folliclecells.Inaddition,twoofthethreepolypeptides(VGP1andVGP2)areproducedatroughlyequallevelsbythefolliclecells,butthesmallestpolypeptide(VGP3)isproducedatone-fourththislevelbythesecells.Hybridizationofclonedgenomicprobes(T.Barnett,C.Pachl,J.P.Gergen,andP.C.Wensink,1980,Cell21,729–738)toRNAboundonnitrocellulosefiltershasshownthattheovarycontributesaproximately35%ofthetotalamountofthemRNAscodingforVGP1andVGP2butonlyabout10%ofthemRNAforVGP3.ThesameproceduredemonstratedthatthelevelsofallthreeVGmRNAsduringfolliculardevelopmentcloselyparallelVGpolypeptidesynthesis.Finally,cultureofovariesinmaleshasshownthatthemRNAlevelsaccuratelyreflectthefolliclecellcontributiontoVGsynthesis.
[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]
