[Mutations in beta'-subunit of the Escherichia coli RNA-polymerase influence interaction with downstream duplex DNA in the elongation complex].
RNA polymerase (RNAP) exhibits absolute processivity being capable of synthesizing RNA 10(3)-10(5) nucleotides in length without breaking contact with the DNA template. Stability of the elongation complex is thought to depend, in particular, on the RNAP-DNA interactions downstream along the run of transcription. We studied the effects of several deletions and insertions in the RNAP beta'-subunit N-terminal region, which presumably interacts with the downstream duplex DNA in the elongation complex. Most of the mutations obtained led to gross defects in RNAP assembly and disturbed catalytic activity of the enzyme. The mutations reduced stability of both promoter and elongation complexes, probably because they altered the contacts between RNAP and the downstream duplex DNA.
Kul'bachinskiĭ
A V
AV
Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182 Russia. akulb@img.ras.ru
Ershova
G V
GV
Korzheva
N V
NV
Brodolin
K L
KL
Nikiforov
V G
VG
D000595:Amino Acid Sequence; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009692:Nucleic Acid Heteroduplexes / Q000378:metabolism*; D010441:Peptide Chain Elongation, Translational; D011401:Promoter Regions, Genetic; D017386:Sequence Homology, Amino Acid
D029968:Escherichia coli Proteins; D009692:Nucleic Acid Heteroduplexes; C108570:beta' subunit of RNA polymerase; D012321:DNA-Directed RNA Polymerases