NELF-E RRM undergoes major structural changes in flexible protein regions on target RNA binding

Biochemistry. 2008 Mar 25;47(12):3756-61. doi: 10.1021/bi702429m. Epub 2008 Feb 28.

Abstract

The E subunit of the human heterotetrameric negative transcription elongation factor (NELF-E) contains a canonical betaalphabetabetaalphabeta RNA recognition motif (RRM) that binds to a wide variety of RNA sequences. These induce very similar conformational changes in the RRM as determined by nuclear magnetic resonance spectroscopy. Although the RNA binding interface of a canonical RRM is mainly located at its beta-sheet surface, for NELF-E RRM large chemical shift perturbations are observed for residues in the flexible C-terminal region and the loop between beta 3 and alpha 2, and both regions are distant from the interface. We determined the solution structure of single-stranded transactivator responsive element (TAR) RNA-bound NELF-E RRM. This structure clearly shows that RNA binding to NELF-E RRM induces formation of a helix in the C-terminus. The RNA-bound form of NELF-E RRM is very similar to the RNA-bound form of U1A RRM, although the C-terminus of the NELF-E RRM is unstructured in the free protein, whereas it is helical in the U1A protein. Thus, RNA binding to NELF-E RRM induces a conformational change toward the U1A structure, resulting in highly similar RNA binding conformations for both proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Base Sequence
  • Humans
  • Models, Molecular
  • Nuclear Magnetic Resonance, Biomolecular
  • Nuclear Proteins / chemistry*
  • Nucleic Acid Conformation
  • RNA-Binding Proteins / chemistry*
  • Ribonucleoprotein, U1 Small Nuclear / chemistry
  • Transcription Factors
  • Transcriptional Elongation Factors / chemistry*

Substances

  • Nuclear Proteins
  • RNA-Binding Proteins
  • Ribonucleoprotein, U1 Small Nuclear
  • TARBP1 protein, human
  • Transcription Factors
  • Transcriptional Elongation Factors
  • U1A protein
  • negative elongation factor

Associated data

  • PDB/2JX2