ER stress signaling requires RHD3, a functionally conserved ER-shaping GTPase

J Cell Sci. 2014 Aug 1;127(Pt 15):3227-32. doi: 10.1242/jcs.147447. Epub 2014 May 29.

Abstract

Whether structure and function are correlated features of organelles is a fundamental question in cell biology. Here, we have assessed the ability of Arabidopsis mutants with a defective endoplasmic reticulum (ER) structure to invoke the unfolded protein response (UPR), an essential ER signaling pathway. Through molecular and genetic approaches, we show that loss of the ER-shaping GTPase Root Hair Defective 3 (RHD3) specifically disrupts the UPR by interfering with the mRNA splicing function of the master regulator IRE1. These findings establish a new role for RHD3 in the ER and support specificity of the effects of ER-shaping mutations on ER function.

Keywords: Arabidopsis; IRE1; RHD3; Unfolded protein response.

Publication types

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

MeSH terms

  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Arabidopsis*
  • Cells, Cultured
  • Endoplasmic Reticulum / genetics
  • Endoplasmic Reticulum / metabolism*
  • Endoplasmic Reticulum Stress / physiology*
  • GTP Phosphohydrolases / metabolism
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism*
  • Mutation / genetics
  • Protein Kinases / genetics
  • Protein Kinases / metabolism*
  • RNA Splicing / genetics
  • Signal Transduction / genetics
  • Structure-Activity Relationship
  • Tunicamycin / metabolism
  • Unfolded Protein Response / drug effects
  • Unfolded Protein Response / genetics

Substances

  • Arabidopsis Proteins
  • Tunicamycin
  • Protein Kinases
  • Ire1-1 protein, Arabidopsis
  • GTP Phosphohydrolases
  • GTP-Binding Proteins
  • RHD3 protein, Arabidopsis