L'utilisation de nucléosides dans l'ovaire du Grillon et ses variations au cours de l'ovogenèse: II. Incorporation dans l'ADN

[摘要] 1.1.WedescribeheretheuptakeoftritiatedcytidineanduridineandofthymidineintheDNAofthecricketovary,anditsvariationswiththetreatmenttimeandthephysiologicalconditionofthefollicles.2.2.ThymidineisusedonlyforDNAsynthesis.Thenumberoflabeledfolliclenucleiincreaseswhenthesecretoryactivitystarts,and,after5minutesofincorporation,approximatelyone-thirdofthenucleiareradioactiveduringthemiddlestageofvitellogenesis.Lateron,thereisnofurtherriseinthenumberoflabelednucleiwithincreasedtreatmenttime.Betweenthefirstandthemiddlestagesofvitellogenesis,theradioactivitybecomeshigherinthenuclei,inrelationwiththeincreasingamountofDNAperpolyploidfolliclenucleus.3.3.Nouptakeofthymidineisvisibleinthegerminalvesicle.Whenthesecretoryactivityofthefolliclecellsreachesitsmaximum,radioactiveDNAoccursintheircytoplasmandintheooplasm.4.4.Followinglongincorporationtimes,theribonucleosidesareusedforDNAsynthesis.Duringvitellogenesis,uridineisincorporatedintoDNAinthesamewayasthymidine.Atthemiddlestageofvitellogenesis,cytidinefollowsaspecialpatternofincorporation:afteratreatmenttimeof24hours,theDNAlabelingextendsto100%ofthefolliclenuclei.TheoriginofthelateDNAprecursorisdiscussed.

[学科分类] 生物科学（综合）