Mapping of Promoter Sites on the Genome of Bacteriophage M13

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Abstract
Transcription studies on restriction fragments of bacteriophage M13 DNA showed that at least 8 promoter sites are located on the M13 genome. Five of these promoters initiate the synthesis of RNA chains which contain at their 5''-terminal end pppG (G promoters), while the other 3 promoters initiate RNA chains which start exclusively with pppA (A promoters). The positions of these promoter sites on the physical map are: 0.82 (G0.82), 0.88 (G0.88), 0.94 (G0.94), 0.01 (G0.01), 0.08 (G0.08), 0.36 (A0.36), 0.51 (A0.51) and 0.56 (A0.56). The G promoters were clustered within a distance of 1/3 of the genome length from the central termination site for transcription (map position 0.77). The A promoters were at greater distances from this termination signal. Based upon the incorporation of [.gamma.-32P]ATP or [.gamma.-32P]GTP, the capacity of these promoters to initiate the synthesis of RNA chains varies. The strongest G promoters are G0.82, G0.94 and G0.08, and the strongest A promoter is A0.36. Judged from their position on the genetic map, 2 promoters, G0.94 and G0.01, are probably located within gene II. The other promoters are most probably located immediately in front of the gene VIII/VII boundary (G0.82) and immediately in front of gene V (G0.88), gene II (G0.08), gene IV (A0.36), gene I (A0.51) and gene VI (A0.56). No evidence was obtained for the existence of a promoter immediately in front of gene III.