The effects of mutations in the ant promoter of phage P22 depend on context
Graduate School of Biomedical Sciences; Department of Molecular Genetics and Microbiology
Life Sciences | Medicine and Health Sciences
Recombination was used to construct 22 two- or three-way combinations of down- and up-mutations in Pant, a strong, near-consensus promoter of phage P22. The relative strengths of these promoters in vivo were assayed by fusing them to an ant/lacZ gene fusion and measuring beta-galactosidase levels produced by lysogens carrying the fusions on single-copy prophages. The results of these assays show that the magnitude of the effect of a promoter mutation can vary considerably when its context is changed by the presence of another mutation. In addition, as Pant approaches conformity with the consensus promoter sequence, the up-mutations decrease promoter strength, even though the same mutations increase promoter strength in the presence of a down-mutation. These context effects imply that individual consensus base pairs cannot be considered to contribute to promoter strength independently.
Genetics. 1988 Oct;120(2):319-27.
Grana D, Gardella TJ, Susskind MM. (1988). The effects of mutations in the ant promoter of phage P22 depend on context. Morningside Graduate School of Biomedical Sciences Student Publications. Retrieved from https://escholarship.umassmed.edu/gsbs_sp/408