Frameshift mutations in the bacteriophage Mu repressor gene can confer a trans-dominant virulent phenotype to the phage.
Virulent mutations in the bacteriophage Mu repressor gene were isolated and characterized. Recombination and DNA sequence analysis have revealed that virulence is due to unusual frameshift mutations which change several C-terminal amino acids. The vir mutations are in the same repressor region as the sts amber mutations which, by eliminating several C-terminal amino acids, suppress thermosensitivity of repressor binding to the operators by its N-terminal domain (J. L. Vogel, N. P. Higgins, L. Desmet, V. Geuskens, and A. Toussaint, unpublished data). Vir repressors bind Mu operators very poorly. Thus the Mu repressor C terminus, either by itself or in conjunction with other phage or host proteins, tunes the DNA-binding properties at the repressor N terminus.
Geuskens
V
V
Laboratoire de Génétique, Université Libre de Bruxelles, Rhode Saint Genèse, Belgium.
Vogel
J L
JL
Grimaud
R
R
Desmet
L
L
Higgins
N P
NP
Toussaint
A
A
D000595:Amino Acid Sequence; D010583:Bacteriophage mu / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D001483:Base Sequence; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016368:Frameshift Mutation / Q000235:genetics*; D005799:Genes, Dominant / Q000235:genetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009875:Operator Regions, Genetic / Q000502:physiology; D010641:Phenotype; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D013696:Temperature; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D054334:Viral Regulatory and Accessory Proteins
D004268:DNA-Binding Proteins; D012097:Repressor Proteins; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C016649:phage repressor proteins