Structural and functional relationships between plasmodesmata and plant endoplasmic reticulum–plasma membrane contact sites consisting of three synaptotagmins

Kazuya Ishikawa, Kentaro Tamura, Yoichiro Fukao, Tomoo Shimada

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

Synaptotagmin 1 (SYT1) has been recognised as a tethering factor of plant endoplasmic reticulum (ER)–plasma membrane (PM) contact sites (EPCSs) and partially localises to around plasmodesmata (PD). However, other components of EPCSs associated with SYT1 and functional links between the EPCSs and PD have not been identified. We explored interactors of SYT1 by immunoprecipitation and mass analysis. The dynamics, morphology and spatial arrangement of the ER in Arabidopsis mutants lacking the EPCS components were investigated using confocal microscopy and electron microscopy. PD permeability of EPCS mutants was assessed using a virus movement protein and free green fluorescent protein (GFP) as indicators. We identified two additional components of the EPCSs, SYT5 and SYT7, that interact with SYT1. The mutants of the three SYTs were defective in the anchoring of the ER to the PM. The ER near the PD entrance appeared to be weakly squeezed in the triple mutant compared with the wild-type. The triple mutant suppressed cell-to-cell movement of the virus movement protein, but not GFP diffusion. We revealed major additional components of EPCS associated with SYT1 and suggested that the EPCSs arranged around the PD squeeze the ER to regulate active transport via PD.

Original languageEnglish
Pages (from-to)798-808
Number of pages11
JournalNew Phytologist
Volume226
Issue number3
DOIs
Publication statusPublished - May 1 2020
Externally publishedYes

Keywords

  • Arabidopsis thaliana
  • cell-to-cell movement
  • endoplasmic reticulum (ER)
  • membrane contact sites
  • plant virus
  • plasma membrane (PM)
  • plasmodesmata (PD)
  • synaptotagmin

ASJC Scopus subject areas

  • Physiology
  • Plant Science

Fingerprint

Dive into the research topics of 'Structural and functional relationships between plasmodesmata and plant endoplasmic reticulum–plasma membrane contact sites consisting of three synaptotagmins'. Together they form a unique fingerprint.

Cite this