Molecular characterization of nucleus-localized RNA-binding proteins from higher plants

Plant Mol Biol. 2002 Mar;48(4):413-21. doi: 10.1023/a:1014089531125.

Abstract

We report the isolation and characterization of genes from the higher plants Arabidopsis, spinach and tobacco which code for nucleus-localized RNA-binding proteins. Common features of these polypeptides are glycine/arginine-rich regions with several RGG repeats at their N- and C-termini, which are sufficient for RNA binding in northwestern assays. All polypeptides analysed contain two basic bipartite nuclear localization signals and translational fusions harbouring these regions with the beta-glucuronidase gene direct the fusion proteins into the nucleus. Nuclear localization was confirmed by cellular fractionation with a polyclonal antiserum raised against the over-expressed tobacco protein NtRGG1p. Two or three copies of related RGG genes appear to be present in the analysed organisms and the expression of some of them is regulated: a tobacco gene is light-regulated and a spinach gene is preferentially expressed in roots. Possible biological functions of this class of RNA-binding proteins as well as structure/function relationships related to the modular structure are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Cell Nucleus / metabolism*
  • DNA, Complementary / genetics
  • DNA, Plant / genetics
  • Glucuronidase / genetics
  • Glucuronidase / metabolism
  • Molecular Sequence Data
  • Nuclear Localization Signals / genetics
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Plants / genetics*
  • Plants / metabolism
  • Protein Binding
  • RNA / metabolism
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Repetitive Sequences, Amino Acid / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Spinacia oleracea / genetics
  • Spinacia oleracea / metabolism
  • Tobacco / genetics
  • Tobacco / metabolism

Substances

  • DNA, Complementary
  • DNA, Plant
  • Nuclear Localization Signals
  • Nuclear Proteins
  • RNA-Binding Proteins
  • Recombinant Fusion Proteins
  • RNA
  • Glucuronidase