The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Higher Plant Calreticulins Have Acquired Specialized Functions in Arabidopsis

På svenska

Author

  • Anna Christensen
  • Karin Svensson
  • Lisa Thelin
  • WenJing Zhang
  • Nico Tintor
  • Daniel Prins
  • Norma Funke
  • Marek Michalak
  • Paul Schulze-Lefert
  • Yusuke Saijo
  • Marianne Sommarin
  • Susanne Widell
  • Staffan Persson
Show all

Summary, in English

Background: Calreticulin (CRT) is a ubiquitous ER protein involved in multiple cellular processes in animals, such as protein folding and calcium homeostasis. Like in animals, plants have evolved divergent CRTs, but their physiological functions are less understood. Arabidopsis contains three CRT proteins, where the two CRTs AtCRT1a and CRT1b represent one subgroup, and AtCRT3 a divergent member. Methodology/Principal Findings: Through expression of single Arabidopsis family members in CRT-deficient mouse fibroblasts we show that both subgroups have retained basic CRT functions, including ER Ca2+-holding potential and putative chaperone capabilities. However, other more general cellular defects due to the absence of CRT in the fibroblasts, such as cell adhesion deficiencies, were not fully restored. Furthermore, in planta expression, protein localization and mutant analyses revealed that the three Arabidopsis CRTs have acquired specialized functions. The AtCRT1a and CRT1b family members appear to be components of a general ER chaperone network. In contrast, and as recently shown, AtCRT3 is associated with immune responses, and is essential for responsiveness to the bacterial Pathogen-Associated Molecular Pattern (PAMP) elf18, derived from elongation factor (EF)-Tu. Whereas constitutively expressed AtCRT1a fully complemented Atcrt1b mutants, AtCRT3 did not. Conclusions/Significance: We conclude that the physiological functions of the two CRT subgroups in Arabidopsis have diverged, resulting in a role for AtCRT3 in PAMP associated responses, and possibly more general chaperone functions for AtCRT1a and CRT1b.

Publishing year

2010

Language

English

Publication/Series

PLoS ONE

Volume

5

Issue

6

Document type

Journal article

Publisher

Public Library of Science (PLoS)

Topic

  • Biological Sciences

Status

Published

ISBN/ISSN/Other

  • ISSN: 1932-6203