Synthesis of satellite DNA in Rhynchosciara hollaenderi☆
[摘要] DuringthelatterpartofthefourthinstardevelopmentofRhynchosciaralarvae,DNAsynthesisoccursinbothgermcellsandsomaticcells,eventhoughthesecellsdonotundergomitosis.CsCldensitygradientanalysishasrevealedthesynthesisofd(AT)satelliteDNAsinthetestisandinsomatictissuessuchassalivarygland,fatbody,andgastriccecum.Inthesestudiesithasbeenshownthatthereisatissue-specificvariationintherelativeproportionsofsynthesisofd(AT)satelliteandmain-bandDNAinthetestisduringthefourthinstar.Theinitiationofsynthesisofthed(AT)satelliteinthetestiscorrespondswiththeappearanceandformationofthehighlycharacteristicmitochondriawhichdevelopduringthematurationofthespermatocytes.ThissatelliteDNAhasbeenshowntobecircularandhasadensityof1.681gm/cm3inCsCl.SynthesisofasimilarcircularDNAcannotbedetectedinsomatictissues,althoughthesetissuesdosynthesizead(AT)satelliteofsimilardensity.WeconcludefromthesestudiesthatthespecificsynthesisofauniquecircularDNAmaybeanessentialpartofthemorphogeneticdevelopmentofthehighlyspecializedmitochondriaformedduringspermatocytematuration.
[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]
