In vivo expression of the rII region of bacteriophage T4 present in chimeric plasmids.

摘要: The expression of the T4 rII genes in uninfected cells has been examined by use recombinant plasmids. Hybridization analysis pulse-labelled RNA prepared from carrying pTB101, a plasmid that contains end gene 60 and beginning rIIA, shows about 0.7% labelled is specific. By contrast, only 0.02% pTB301, which probably middle-mode rIB promoter, may be When separated strands DNA were used for hybridization, we found pTB101 transcripts have strand specificity identical to rIIA made during phage infection. same was observed irrespective orientation inserted vector. This result argues initiate within rather than somewhere else on plasmid. We also essentially none would hybridize deletion mutant lacks gene. suggests little being transcribed. In addition transcript, new protein 56,000 Daltons molecular weight pTB101. Fingerprint it specified Taken together, these results indicate transcription initiates at or near