Regulation of polysome formation in etiolated bean leaves by light☆
[摘要] Thekineticsofformationofcytoplasmicandplastidpolysomesfollowingbriefilluminationofetiolatedbeanleaveswasstudied.TheOD260patternsofribosomesseparatedonsucrosegradientswereanalyzedbycomputertodeterminetherelativeareasundermonosomeandpolysomepeaks.A3-foldincreaseincytoplasmicpolysomesoccurs,starting2hrafterredilluminationandreachinganewsteadystateatabout10hr.Thespecificeffectsoffar-redlightdependonthelengthofthedarkperiodbetweentheoriginalredstimulusandtheadministrationoffarred.Theseeffectsrangefromadecreaseinthepolysomes,alowermaximumlevel,alowerrateofincreasetopreventionofanynewpolysomeformationasthedarkperioddecreases.Thetimerequiredforthemanifestationoffar-redeffectsisalso2hr.Plastidpolysomesincreasemorethanthecytoplasmicafterasingleredillumination,evenmoreafterrepeatedred,butareaffectedequallybyfar-redreversal.32P-labelingofribosomalRNAshowednomeasurableincreaseduringthefirst2hrafterredillumination.ThuslightaffectspolysomeformationwithoutsignificantlyaffectingribosomalRNAsynthesis.
[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]
