sn-glycerol-3-phosphate dehydrogenase gene expression during mouse adipocyte development in vivo☆

[摘要] Cytoplasmiclipiddropletsbegintoformat3dayspostpartumintheepididymalfatpadofthemouse.sn-Glycerol-3-phosphatedehydrogenase(GPDH,EC1.1.1.8)specificactivityincreasedupto100-foldduringadipocyteterminaldifferentiation,andallofthisincreasewasduetotheadultGPDHisozyme.Theembryonicisozymedidnotappeartoparticipateinlipidaccumulation.ImmunohistochemicallocalizationofadultGPDHinfatpadsectionsshowedthatallcellswithlipiddropletswereGPDHpositiveandclusteredtogetherindefinedcolonies.ThedevelopmentalincreaseinGPDHlevelswasaccompaniedbyinclusionofGPDH-negativecellsintheclustersofGPDH-positivecells.Theabsenceofanylipid-containingGPDH-negativecellsindicatesthattheincreaseintheadultisozymeplaysanimportantroleinlipidaccumulationduringadipocytedevelopment.TheadultGPDHstructuralgene,Gdc-1,isexpressedincellswhicharereplicatingtheirDNA.Tritiatedthymidine-labelingexperimentsshowedthat10%ofthecellsinthe1-dayepididymalfatpadweresynthesizingDNAatagiventime.Thelabelingindexdecreasedto1%at12daysinbothGPDH-positiveandGPDH-negativecells.NosignificantdifferenceinlabelingindicescouldbefoundbetweenGPDH-positiveandGPDH-negativecellsatallagesstudied.

[学科分类] 生物科学（综合）