Structure and RNA-binding properties of the bacterial LSm protein Hfq

RNA Biol. 2013 Apr;10(4):610-8. doi: 10.4161/rna.24201. Epub 2013 Mar 27.

Abstract

Over the past years, small non-coding RNAs (sRNAs) emerged as important modulators of gene expression in bacteria. Guided by partial sequence complementarity, these sRNAs interact with target mRNAs and eventually affect transcript stability and translation. The physiological function of sRNAs depends on the protein Hfq, which binds sRNAs in the cell and promotes the interaction with their mRNA targets. This important physiological function of Hfq as a central hub of sRNA-mediated regulation made it one of the most intensely studied proteins in bacteria. Recently, a new model for sRNA binding by Hfq has been proposed that involves the direct recognition of the sRNA 3' end and interactions of the sRNA body with the lateral RNA-binding surface of Hfq. This review summarizes the current understanding of the RNA binding properties of Hfq and its (s)RNA complexes. Moreover, the implications of the new binding model for sRNA-mediated regulation are discussed.

Keywords: 3′ end recognition; LSm ring; RNA chaperone; RNA degradation; crystal structure; gene regulation; non-coding RNAs; prokaryotes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Binding Sites
  • Escherichia coli / chemistry*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism
  • Eukaryota / chemistry
  • Eukaryota / genetics
  • Eukaryota / metabolism
  • Gene Expression Regulation, Bacterial
  • Host Factor 1 Protein / chemistry*
  • Host Factor 1 Protein / metabolism*
  • Humans
  • Phylogeny
  • Protein Binding / genetics
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins / metabolism
  • RNA Stability
  • RNA, Bacterial / genetics
  • RNA, Bacterial / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • RNA, Small Untranslated / genetics
  • RNA, Small Untranslated / metabolism*
  • RNA-Binding Proteins / chemistry
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*
  • Salmonella typhimurium / chemistry*
  • Salmonella typhimurium / genetics
  • Salmonella typhimurium / metabolism
  • Sequence Alignment

Substances

  • Bacterial Proteins
  • Escherichia coli Proteins
  • Host Factor 1 Protein
  • LSM1 protein, human
  • Proto-Oncogene Proteins
  • RNA, Bacterial
  • RNA, Messenger
  • RNA, Small Untranslated
  • RNA-Binding Proteins