Mitochondrial development during myogenesis☆
[摘要] Theenzymaticandultrastructuralpatternofmitochondrialdifferentiationwasinvestigatedduringmyogenesis.SuccinatecytochromeCreductase(SCR),amitochondrialenzymecomplex,increasedinactivityindevelopingchickthighmuscleinvivoandinvitro.SCRincreaseinvitrooccurredsubsequenttomyoblastfusionandcorrelatedwiththeperiodofincreasingcreatinephosphokinase(CPK)activity.Fusion-arrestandCa2+-reversalexperimentsindicatedanapparentcoordinationbetweenCPKandSCRenzymaticincreasesandfusion.AnalysisofSCRactivityinfibroblastculturessuggestedthattheenzymaticincreasesobservedindifferentiatingmuscleculturesreflectedmyocytedifferentiation,ratherthanfibroblastcontaminationorauniquepropertyofthetissuecultureenvironment.MorphologicaltransitionsinthemyogenicmitochondriaweretemporallycorrelatedwithincreasedSCRactivity.Duringmyogenesis,themitochondriaenlargedinlengthandvolume,exhibitedanincreaseinmatrixdensity,orientedinparalleltothelongaxisofthemyofibrils,andcontainedincreasednumbersofparallelcristae.Manymitochondriainfusion-inhibitedmuscleculturesresembledthosefoundinprefusionmyoblasts,althoughmaturemitochondriawereobservedinsomefusion-blockedcells.Quantitativestereologicalanalysesofthesemitochondrialchangesparallelthebiochemicaldataandsuggestthatultrastructuralandenzymaticchangesinthemitochondriaareanintegralpartofmyodifferentiation.
[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]
