to test whether the increased expression of the transferred gene which occurred during differentiation was determined by dna sequences in the 5 ' region of the muscle actin gene , a plasmid ( p alpha-cat ) containing 730 bp of the 5 ' flanking region of the rat skeletal muscle actin gene ( plus the exon of the 5 ' untranslated region , and 25 bp of the first intron ) , spliced to the bacterial structural gene coding for chloramphenicol acetyl transferase ( cat ) , was constructed and introduced into l8 cells .
C0007589
differentiation
C0007634
cells