Isoform-specific subcellular localization among 14-3-3 proteins in Arabidopsis seems to be driven by client interactions

Mol Biol Cell. 2005 Apr;16(4):1735-43. doi: 10.1091/mbc.e04-09-0839. Epub 2005 Jan 19.

Abstract

In most higher eukaryotes, the predominantly phosphoprotein-binding 14-3-3 proteins are the products of a multigene family, with many organisms having 10 or more family members. However, current models for 14-3-3/phosphopeptide interactions suggest that there is little specificity among 14-3-3s for diverse phosphopeptide clients. Therefore, the existence of sequence diversity among 14-3-3s within a single organism begs questions regarding the in vivo specificities of the interactions between the various 14-3-3s and their clients. Chief among those questions is, Do the different 14-3-3 isoforms interact with different clients within the same cell? Although the members of the Arabidopsis 14-3-3 family of proteins typically contain highly conserved regions of sequence, they also display distinctive variability with deep evolutionary roots. In the current study, a survey of several Arabidopsis 14-3-3/GFP fusions revealed that 14-3-3s demonstrate distinct and differential patterns of subcellular distribution, by using trichomes and stomate guard cells as in vivo experimental cellular contexts. The effects of client interaction on 14-3-3 localization were further analyzed by disrupting the partnering with peptide and chemical agents. Results indicate that 14-3-3 localization is both isoform specific and highly dependent upon interaction with cellular clients.

Publication types

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

MeSH terms

  • 14-3-3 Proteins / genetics
  • 14-3-3 Proteins / metabolism*
  • Aminoimidazole Carboxamide / analogs & derivatives
  • Aminoimidazole Carboxamide / metabolism
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Protein Binding
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Protein Transport
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Ribonucleotides / metabolism

Substances

  • 14-3-3 Proteins
  • Protein Isoforms
  • Recombinant Fusion Proteins
  • Ribonucleotides
  • Aminoimidazole Carboxamide
  • AICA ribonucleotide