DNA sequences flanking the starts of the hsp 70 and αβ heat shock genes are homologous☆
[摘要] The87A7and87C1cytogeneticlociofD.melanogastercontaintwodifferenttypesofheat-induciblegenes.Oneofthesecodesforthe70,000-daltonheatshockprotein(hsp70)andispresentatbothloci,whiletheothergene,αβ,codesforanRNAofunknownfunctionandisfoundonlyat87C1.Wefindthatrestrictionfragmentsthatmapadjacenttothe5′endofthehsp70genehybridizetofragmentsthatmapadjacenttothe5′endofαβ.ElectronmicroscopicmappingofduplexDNAformedbetweensegmentsthatcontainthesedifferentgenesrevealsanextensivehomologousregionofseveralhundredbasepairsthatisadjacenttothestartoftherespectivetranscriptionunits.AsubclonedDNAsegmentthatmapsentirelywithinthishomologousregionhybridizesinsituexclusivelytoloci87Aand87Conpolytenechromosomes.Wenoteinparticulartheabsenceofdetectablehybridizationatotherheatshockloci—evenwithlongautoradiographicexposure.WeproposethatthehomologywhichisrestrictedtothissubsetoftheheatshockgenesistheresultofarecenttranspositionofαβDNAadjacenttoacopyoftheregulatoryregionofthehsp70gene,therebyplacingexpressionofαβundercontroloftheheatshockresponse.
[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]
