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

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.

SUBMITTER: Lai YS

PROVIDER: S-EPMC4117228 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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

Lai Ya-Shiuan YS Stefano Giovanni G Brandizzi Federica F

Journal of cell science 20140529 Pt 15

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 ...[more]

PMID: 24876222

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