Sequence tolerance of the phage lambda PRM promoter: implications for evolution of gene regulatory circuitry.

ABSTRACT: Much of the gene regulatory circuitry of phage lambda centers on a complex region called the O(R) region. This approximately 100-bp region is densely packed with regulatory sites, including two promoters and three repressor-binding sites. The dense packing of this region is likely to impose severe constraints on its ability to change during evolution, raising the question of how the specific arrangement of sites and their exact sequences could evolve to their present form. Here we ask whether the sequence of a cis-acting site can be widely varied while retaining its function; if it can, evolution could proceed by a larger number of paths. To help address this question, we developed a lambda cloning vector that allowed us to clone fragments spanning the O(R) region. By using this vector, we

SUBMITTER: Michalowski CB 

PROVIDER: S-EPMC529058 | biostudies-literature | 2004 Dec

REPOSITORIES: biostudies-literature