Fine analysis of the chromatin structure of yeast RNA polymerase Ⅱ transcription teminators

摘要

In order to study the functional structure of the transcription terminators and the mechanism of temination,a survey of the chromatin structure,including the location of DNase I hypersensitive sites and the nucleosome arrangement,of yeast ADH1 and FLP terminators was made.The results show that there is no relationship between the function of the terminators and the existence of DNase I hypersensitive sites.However,it is found that there is always a nucleosmoe at the immediate upstream of the transcriptional termination sites.As a control,the chromatin structures of the pBR322 DNA fragments on the yeast shutter vectors are also investigated at the same time.The random nucleosome arrangement on the bacterial DNA in yesast agrees with the published reports.A new hypothesis,about the mechanism of transcriptional termination is put forward and the reason of different nucleosome arrengement on the DNAs which are originally from different species in yeast is discussed.