Figure 8-2: Maps of phage λ. The maps are to scale, as indicated; not all genes are shown. a) Map of the right half of the λ genome. Genes mentioned in the text are shown; in addition, att is the site of site-specific recombination for integrating and excising the prophage; xis is required for prophage excision; S and R are involved in cell lysis; and Q is an anti-termination protein for transcripts initiating at the late lytic promoter P_R', which otherwise terminate before S. Transcripts from the P_I, P_L, PR and P_R' promoters are shown. b) Close-up of the O_L region; this region is organized similarly to the O_R region, except that it lacks a oppositely-directed promoter analogous to P_RM. c) Close-up of the region around O_R. Locations of the P_R, P_RM and P_RE promoters and their transcripts are shown. cro is translated from the P_R transcript, not from the P_RE transcript. d) Extreme close-up of the O_R region. Only the initial portions of the cI and cro genes are shown. The P_RM message starts with the AUG start codon of cI, and lacks a Shine-Dalgarno sequence. (for better image quality, click here for tif image, which may be quite large; may also require screen refreshing plus special software to view; or view larger tif in separate window)

Figure 8-1, Figure 8-2, Figure 8-3, Figure 8-4

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