title: Bacteriophage phiX174: gene A overlaps gene B.
abstract: The map position of several phiX174 mutations in the genes A and B was determined by marker rescue with DNA fragments produced by the restriction enzymes Hha I, HindII, Hae III, and Alu I. All the gene B mutants were found to be located within gene A. Genetic complementation and analysis of phage-specific protein synthesis show that, under restrictive conditions, nonsense mutants in gene A do not block the synthesis and activity of the B protein and nonsense mutants in gene B do not affect the gene A function. The map position of the COOH-terminal end of gene A was determined using an amber mutant that synthesizes slightly shortened A and A proteins. It is concluded from these experiments that gene A overlaps gene B completely (or almost completely) and that the overlap region can be translated in two ways with different reading frames: one frame for the synthesis of the A and A proteins and another for the synthesis of the B protein.
mesh_terms: D003090:Coliphages / Q000378:metabolism / Q000648:ultrastructure*; D004262:DNA Restriction Enzymes; D004279:DNA, Viral / Q000378:metabolism; D005796:Genes; D005815:Genetic Code; D008970:Molecular Weight; D009154:Mutation; D014176:Protein Biosynthesis; D013045:Species Specificity; D014764:Viral Proteins / Q000096:biosynthesis
chemical_list: D004279:DNA, Viral; D014764:Viral Proteins; D004262:DNA Restriction Enzymes
references.citation: J Mol Biol. 1976 Jun 5;103(4):699-710
references.pmid: 781283
references.citation: J Virol. 1972 Jul;10(1):99-114
references.pmid: 16789133
references.citation: Nature. 1977 Feb 24;265(5596):702-5
references.pmid: 859575
references.citation: Nature. 1976 Nov 4;264(5581):34-41
references.pmid: 1004533
references.citation: Virology. 1975 Nov;68(1):221-33
references.pmid: 1081295
references.citation: Virology. 1976 Jul 1;72(1):61-71
references.pmid: 1084616
references.citation: Nucleic Acids Res. 1976 Aug;3(8):1947-60
references.pmid: 1085927
references.citation: J Mol Biol. 1975 May 25;94(3):441-8
references.pmid: 1100841
references.citation: J Virol. 1976 Apr;18(1):218-26
references.pmid: 1255871
references.citation: Nature. 1976 May 20;261(5557):245-8
references.pmid: 1272397
references.citation: Nat New Biol. 1973 Sep 5;245(140):6-8
references.pmid: 4516942
references.citation: Virology. 1972 Nov;50(2):381-7
references.pmid: 4564522
references.citation: J Virol. 1974 Nov;14(5):1142-51
references.pmid: 4610178
references.citation: J Mol Biol. 1974 Oct 15;89(1):1-16
references.pmid: 4613851
references.citation: Eur J Biochem. 1974 Jul 1;46(1):83-8
references.pmid: 4850204
references.citation: J Mol Biol. 1962 Mar;4:142-60
references.pmid: 13913400
references.citation: Virology. 1965 Feb;25:303-21
references.pmid: 14297217
references.citation: J Virol. 1971 May;7(5):549-58
references.pmid: 16789129
references.citation: J Mol Biol. 1976 Oct 15;107(1):1-24
references.pmid: 826639