The bridge helix coordinates movements of modules in RNA polymerase

BMC Biol. 2010 Nov 29;8:141. doi: 10.1186/1741-7007-8-141.


The RNA polymerase 'bridge helix' is a metastable α-helix that spans the leading edge of the enzyme active-site cleft. A new study published in BMC Biology reveals surprising tolerance to helix-disrupting changes in a region previously thought crucial for translocation, and suggests roles for two hinge-like segments of the bridge helix in coordinating modules that move during the nucleotide-addition cycle.

Publication types

  • Editorial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Catalysis
  • Catalytic Domain / genetics
  • DNA-Directed RNA Polymerases / chemistry*
  • Models, Molecular*
  • Molecular Sequence Data
  • Protein Structure, Secondary / genetics*
  • Protein Structure, Tertiary / genetics*


  • DNA-Directed RNA Polymerases