Control of actin synthesis during the development of Acanthamoeba castellanii☆
[摘要] TheregulationofactinsynthesiswasexaminedinencystingcellsofAcanthamoebacastellanii.Proteinswereradiolabeledinvivoatdifferentstagesofdevelopment.Theseparationofproteinsbytwo-dimensionalgelelectrophoresisrevealedtheexistenceofatleastthreeformsofactin,eachdifferingslightlyinisoelectricpoint.ThesethreeactinproteinswerealsodetectedifamoebaRNAwastranslatedinawheatgermsystemorareticulocytelysatesystem.Nearlynoactinproteinsynthesiscouldbedetectedatlatestagesofdevelopment.RNAisolatedfromcysts,however,iscapableofdirectingthesynthesisofthethreeactinproteinsinvitro.Therelativeratesoftheinvivoandinvitroactintranslationarereducedabouttwofoldatearlierstagesofdevelopment.Duringsubsequentstagesofdevelopment,therelativecontentofactinmRNAdoesnotchange,whereastherelativerateofactinsynthesisisreducedabout20-foldatlatestagesofdevelopment.Thisresultsuggeststhereissomekindoflatetranslationalregulationofactinsynthesis.ThechangesinthepatternofpolysomesandinthesubcellulardistributionofmRNAindicateapronouncedreductionintheinitiationofproteinsynthesisatlatestagesofdevelopment.AssumingthatdifferentmRNAshavedifferentaffinitiesforribosomesubunitsorotherfactorsintheinitiationprocess,thepreferentialinhibitionofactinsynthesismightindicatearelativelylowrateconstantforchaininitiation.
[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]
