Coordinate regulation of enzyme inducibility and developmental competence in Aspergillus nidulans☆
[摘要] SporesofthefungusAspergillusnidulansgerminatedindefinedliquidmediumandproducedhyphaewhichgrewassubmergedundifferentiatedcultures.Theabilityofculturesofvariousagestorespondtoenzymeinductiveconditionswasdetermined.Intracellularnitratereductasewasinducedbyadditionofnitratetodefinedgrowthmedium;extracellularneutralproteasewasinducedbyremovalofsulfur.Theseenzymesaremetabolicallyunrelated,andnotrequiredforgrowthordifferentiation.At23–26hrafterinoculationofspores,growingculturesunderwentadistinctdecreaseintheirinductionresponseforeachinducibleenzyme.Growingculturesmaintainedtheactivityoftheconstitutiveenzymeglucose-6-phosphatedehydrogenase.Thechangeintheabilityofculturestorespondtobiochemicalinductivestimulioccurredatthesametimethatculturesbecamedevelopmentallycompetenttorespondtoamorphologicalinductivestimulus.Theconcurrentchangesintheabilityofculturestorespondtoenzymaticandmorphologicalinductionwasnotduetochangesingrowthrate,depletionofmedium,inhibitorproduction,ortoaninabilitytomaintainenzymeactivities.Thechangeswereindependentofanyspecificinductionstimulus.Themechanismresponsibleforthepleiotropiceffectsappearstobeendogenouslycontrolled.Theseresultssuggesttheexistenceineukaryotesofamechanismforthecoordinatedregulationofpotentialtoexpressfacultativefunctions.
[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]
