Format

Send to

Choose Destination
J Mol Biol. 1988 Jan 5;199(1):95-105.

Dominance in lambda S mutations and evidence for translational control.

Author information

1
Department of Biology, Texas A & M University, College Station 77843.

Abstract

Phenotypic analysis of a collection of point mutations in the lysis gene S of bacteriophage lambda indicates that many of the S alleles exhibit at least partially dominant character, suggesting that the S gene product (gpS) must oligomerize to achieve its lethal membrane effect. Moreover, mutations found 5' to the coding sequence also show a dominant character and appear to define a site, designated sdi (structure directed initiation) where mRNA secondary structure controls the choice of initiation codons. We propose that formation of the sdi structure occludes the consensus Shine-Dalgarno sequence and results in initiation at the Met3 codon, generating a lethal 105 residue polypeptide. The model predicts that, in the absence of the sdi stem-and-loop, initiation occurs at the Met1 codon, generating a 107 residue polypeptide, which is a non-lethal inhibitor of lysis. In support of the model, alteration of the first codon was achieved using site-directed mutagenesis, resulting in an S allele that is more lethal and induces lysis significantly sooner than the wild-type.

PMID:
2965249
DOI:
10.1016/0022-2836(88)90381-6
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center