Cell-free transcription and translation of isolated restriction fragments localize bacteriophage T5 pre-early genes.

In vitro transcription and translation of isolated restriction fragments containing all or part of the terminal redundancies of bacteriophage T5 localized virtually every pre-early gene to a small 6.3-kilobase BglI fragment. Among these genes were those encoding the A1 and A2 proteins, which are responsible for complete entry of the viral genome into its host, and the deoxynucleoside 5'-monophosphatase. A 3.9-kilobase BglI fragment containing the remainder of the pre-early region induced no proteins under these same conditions. Proteins induced by fragments including the right and left terminal redundancies were also compared and found to be identical. DNA immediately flanking the pre-early regions induced few proteins in vitro. Thus, this technique has allowed the overall gene organization of the pre-early region of T5 to be described.