Temperature-shift analysis of conidial development in Aspergillus nidulans☆
[摘要] Temperature-shiftexperimentshavebeenperformedonspore-originatedcoloniesof11thermosensitiveaconidialmutantsofAspergillusnidulansinordertodeterminethelatesttimeofshifttotherestrictivetemperaturethatpreventstheinitiationofconidiation.Thistimedefinesthebeginningofthethermosensitiveperiod(TSP)ofthemutant.EightofthemutantshaveTSPsthatbegininthe7-hourperiod(32–39hr)justpriortothefirstappearanceofconidia-bearingstructures,while3ofthemutantshaveTSPsthatbeginlaterandveryclosetothetimeofonsetofconidiation(45hr).ThusnomutantofthesethasaTSPthatbeginsduringthefirst32hrofvegetativegrowthofspore-originatedcolonies.Forallmutants,anupshiftperformedafterthebeginningoftheTSPallowsinitiationofconidiationatclosetothenormaltimeandatthenormalrate,butresultsinanabruptcessationofconidiationatsomefixedtimeafterupshift,characteristicofthemutant.ThemutantwhoseTSPbeginstheearliest(aco-49)isexceptionalinthat,ifconidiationissuppressedbygrowthofcoloniesinsubmergedculture,thismutantbecomesthermoinsensitiveduringvegetativesubmergedgrowth;incontrast,theremaining10mutantsbecomethermoinsensitiveonlyafterthesuppressiveconditionhasbeenrelieved.Wediscussthepossibilitythatthisexceptionalmutantisdefectiveinafunctionrequiredforinitiationoftheprocessthatultimatelyresultsintheformationofconidia.
[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]
