![]() No similar sequence exists in analogous positions upstream from the 5′ end of all of the ovalbumin exons (17, and our unpublished results). Hogness, personal communication) which is of the form 5′-TATAAATA-3′ and has been found in an analogous location upstream from the startpoint of transcription of several genes. This region of homology which may be a common interacting promoter site is very similar to the “Hogness box” (D. ![]() 8, there is clearly a 7 bp AT-rich region of approximate homology centred at about 28 bp from the initial nucleotide of the mRNAs. When these sequences are aligned so as to emphasize sequence homologies as shown in Fig. Lacy personal communications), mouse β globin major ( 41) and Adenovirus-2 major late ( 22) genes. In a search for such sequences, we have compared ( 14) the DNA sequences upstream from the cap site for ovalbumin, rabbit β globin (J. Assuming that the ovalbumin mRNA cap site and the startpoint for transcription are coincident (see above), sites analogous to the prokaryotic common interacting promoter sites could be contained within the region upstream from the leader-coding sequence. The recognition site is a region centred at about 32 base pairs before the beginning of the mRNA and has a structure clearly related to the sequence 5′-TGTTGACATTT-3′ (see 40 for references). The Pribnow box, which is of the form 5′-TATAATG-3′, precedes the transcription-initiation site by 5 to 7 nucleotides and belongs to the model sequence where the upper and lower case letters correspond to bases present at high and moderate frequency, respectively (see Ref. Most sequenced prokaryotic promoters have two common interacting sites, the Pribnow box and the recognition site (for references, see 40). A promoter is functionally defined in prokaryotes as the region of the DNA which precedes a transcription unit and indicates the startpoint for RNA polymerase.
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