The co-chaperone p23 controls root development through the modulation of auxin distribution in the Arabidopsis root meristem

J Exp Bot. 2015 Aug;66(16):5113-22. doi: 10.1093/jxb/erv330. Epub 2015 Jul 10.

Abstract

Homologues of the p23 co-chaperone of HSP90 are present in all eukaryotes, suggesting conserved functions for this protein throughout evolution. Although p23 has been extensively studied in animal systems, little is known about its function in plants. In the present study, the functional characterization of the two isoforms of p23 in Arabidopsis thaliana is reported, suggesting a key role of p23 in the regulation of root development. Arabidopsis p23 mutants, for either form, show a short root length phenotype with a reduced meristem length. In the root meristem a low auxin level associated with a smaller auxin gradient was observed. A decrease in the expression levels of PIN FORMED PROTEIN (PIN)1, PIN3, and PIN7, contextually to an inefficient polar localization of PIN1, was detected. Collectively these results suggest that both Arabidopsis p23 isoforms are required for root growth, in particular in the maintenance of the root meristem, where the proteins are located.

Keywords: Arabidopsis; auxin; p23-chaperone; pin formed protein (PIN); polar auxin transport; root growth..

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism*
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant*
  • Indoleacetic Acids / metabolism*
  • Meristem / metabolism
  • Molecular Chaperones / genetics*
  • Molecular Chaperones / metabolism*
  • Plant Growth Regulators / metabolism*
  • Plant Roots / growth & development
  • Plant Roots / metabolism

Substances

  • Arabidopsis Proteins
  • Indoleacetic Acids
  • Molecular Chaperones
  • Plant Growth Regulators
  • p23 protein, Arabidopsis