dna fragments located 10 kilobases apart in the genome and containing , respectively , the first myosin light chain 1 ( mlc1f ) and the first myosin light chain 3 ( mlc3f ) specific exon of the rat myosin light chain 1 and 3 gene , together with several hundred base pairs of upstream flanking sequences , have been shown in runoff in vitro transcription assays to direct initiation of transcription at the cap sites of mlc1f and mlc3f mrnas used in vivo .
C0040649
transcription
C1158830
initiation