Solution structure of the second RNA recognition motif (RRM) domain of murine T cell intracellular antigen-1 (TIA-1) and its RNA recognition mode

Biochemistry. 2008 Jun 17;47(24):6437-50. doi: 10.1021/bi7024723. Epub 2008 May 24.

Abstract

T cell intracellular antigen-1 (TIA-1), an apoptosis promoting factor, functions as a splicing regulator for the Fas pre-mRNA. TIA-1 possesses three RNA recognition motifs (RRMs) and a glutamine-rich domain. The second RRM (RRM2) is necessary and sufficient for tight, sequence-specific binding to the uridine-rich sequences buried around the 5' splice sites. In the present study, we solved the solution structure of the murine TIA-1 RRM2 by heteronuclear-nuclear magnetic resonance spectroscopy. The TIA-1 RRM2 adopts the RRM fold (betaalphabetabetaalphabeta) and possesses an extra beta-strand between beta2 and beta3, which forms an additional beta-sheet with the C-terminal part of beta2. We refer to this structure as the beta2-beta2' beta-loop. Interestingly, this characteristic beta-loop structure is conserved among a number of RRMs, including the U2AF65 RRM2 and the Sex-lethal RRM1 and RRM2, which also bind to uridine-rich RNAs. Furthermore, we identified a new sequence motif in the beta2-beta2' beta-loop, the DxxT motif. Chemical shift perturbation analyses of both the main and side chains upon binding to the uridine pentamer RNA revealed that most of the beta-sheet surface, including the beta2-beta2' beta-loop, is involved in the RNA binding. An investigation of the chemical shift perturbation revealed similarity in the RNA recognition modes between the TIA-1 and U2AF65 RRMs.

Publication types

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

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Conserved Sequence
  • Crystallography, X-Ray
  • Humans
  • Intracellular Fluid / chemistry
  • Intracellular Fluid / metabolism
  • Intracellular Fluid / physiology
  • Magnetic Resonance Spectroscopy
  • Mice
  • Molecular Sequence Data
  • Multigene Family
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / metabolism
  • Nuclear Proteins / physiology
  • Protein Conformation
  • Protein Structure, Tertiary
  • RNA Splicing*
  • RNA-Binding Proteins / chemistry*
  • RNA-Binding Proteins / metabolism*
  • RNA-Binding Proteins / physiology
  • Ribonucleoproteins / chemistry
  • Ribonucleoproteins / metabolism
  • Ribonucleoproteins / physiology
  • Solutions
  • Splicing Factor U2AF
  • Surface Properties
  • T-Cell Intracellular Antigen-1

Substances

  • Nuclear Proteins
  • RNA-Binding Proteins
  • Ribonucleoproteins
  • Solutions
  • Splicing Factor U2AF
  • T-Cell Intracellular Antigen-1
  • Tia1 protein, mouse
  • U2AF2 protein, human
  • Zrsr1 protein, mouse

Associated data

  • PDB/2RNE