the fact that the poly g-binding , deoxycytidylate ( dc ) -rich clusters are restricted to the in vivo transcribing h strand , together with the absence of thymine-rich clusters in t7 dna , is compatible with the hypothesis ( szybalski et al. , 1966 ) that pyrimidine-rich clusters are related to rna transcription , possibly as the initiation and termination sites .
C0035668
rna
C0040649
transcription