Blocking of the initiation-to-elongation transition by a transdominant RNA polymerase mutation.
RNA polymerase, the principal enzyme of gene expression, possesses structural features conserved in evolution. A substitution of an evolutionarily invariant amino acid (Lys1065----Arg) in the beta subunit of Escherichia coli RNA polymerase apparently disrupts its catalytic center. The mutant protein inhibited cell growth when expressed from an inducible promoter. The assembled holoenzyme carrying the mutant subunit formed stable promoter complexes that continuously synthesized promoter-specific dinucleotides but that did not enter the elongation step. The mutant polymerase inhibited transcription by blocking the access of the wild-type enzyme to promoters.
Institute of Molecular Genetics, U.S.S.R. Academy of Sciences, Moscow.
M
M
Kashlev
J
J
Lee
K
K
Zalenskaya
V
V
Nikiforov
A
A
Goldfarb
D000595:Amino Acid Sequence; D004252:DNA Mutational Analysis; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005799:Genes, Dominant; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012313:RNA / Q000096:biosynthesis; D013329:Structure-Activity Relationship
D012313:RNA; D012321:DNA-Directed RNA Polymerases