title: IS elements in bacteriophage lambda gene cI prevent expression of gene rex.
abstract: IS5 inserted into gene cI of bacteriophage lambda greatly reduces the synthesis of Rex protein. Two other IS insertions in cI are even more polar, but two amber mutations near the 5' end of cI allow normal expression of Rex.
mesh_terms: D010582:Bacteriophage lambda / Q000235:genetics* / Q000502:physiology; D004251:DNA Transposable Elements; D005786:Gene Expression Regulation; D005814:Genes, Viral; D008242:Lysogeny; D009154:Mutation; D014764:Viral Proteins / Q000096:biosynthesis
chemical_list: D004251:DNA Transposable Elements; D014764:Viral Proteins