The phage RNA polymerases are related to DNA polymerases and reverse transcriptases

Mol Microbiol. 1993 Oct;10(1):1-6. doi: 10.1111/j.1365-2958.1993.tb00897.x.


The single subunit DNA-dependent RNA polymerase (RNAP) that is encoded by bacteriophage T7 is the prototype of a class of relatively simple RNAPs that includes the RNAPs of the related phages T3 and SP6, as well as the mitochondrial RNAPs. The T7 enzyme has been crystallized, and recent genetic and biochemical analyses have facilitated an interpretation of this structure. A growing body of evidence suggests that the phage-like RNAPs are related to other nucleotide polymerases such as DNA polymerases, RNA-dependent RNA polymerases, and reverse transcriptases. In this work, we review information concerning the structure and function of T7 RNAP, and evidence in support of its assignment to a broader class of nucleotide polymerases.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Amino Acid Sequence
  • Bacteriophages / enzymology*
  • Binding Sites
  • DNA-Directed DNA Polymerase / chemistry*
  • DNA-Directed RNA Polymerases / chemistry*
  • Molecular Sequence Data
  • Protein Structure, Tertiary
  • RNA-Directed DNA Polymerase / chemistry*
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • T-Phages / enzymology
  • Viral Proteins / chemistry*


  • Viral Proteins
  • bacteriophage T7 RNA polymerase
  • RNA-Directed DNA Polymerase
  • DNA-Directed RNA Polymerases
  • DNA-Directed DNA Polymerase