Transcription of the nuclear and chloroplast genomes during the vegetative cell cycle in Chlamydomonas reinhardi☆
[摘要] ThefractionsofthenuclearandchloroplastgenomesrepresentedbyRNAtranscriptsinasynchronousorsynchronousChlamydomonasreinhardicellsatdifferentcellcyclestagesweremeasuredusingRNA-drivenRNA:DNAhybridizationreactions.ThebulkofthenuclearandchloroplastDNAhybridizationreactionsweredrivenbyaclassofhighlycomplexRNAtranscriptspresentinfewcopiespercell.HybridizationsaturationvaluesobtaineddirectlyorbyextrapolationwithwholecellRNAfromasynchronouscells(representingallcellcyclestages)showedthat12%ofthenucleargenome(about12,000geneequivalents)andallofthechloroplastgenome(about200–300geneequivalents)aretranscribed.RNAextractedfromsynchronouscellsatdifferentcellcyclestagesgenerallyhybridizedtolesserfractionsofeithergenomethandidRNAextractedfromasynchronouscells.Duringthecellcycle,increasingfractionsofboththenuclearandchloroplastgenomesaretranscribedatearlycellcyclestages(lightperiod)butlater,nearthetimeofcelldivision,lesserportionsofeithergenomearerepresentedasRNAtranscriptsinthecell.Thefractionsofthegenomestranscribedatdifferentcellcyclestagesarepartiallyadditive,indicatingthatcertainRNAtranscriptsarecommontoallcellcyclestageswhileothersarenot.TheseresultsindicatethatC.reinhardicellshaveapartlychangingbatteryofhighlycomplexRNAtranscriptsavailableatdifferentcellcyclestages.
[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]
