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Title: An evolutionarily conserved motif is required for Plasmodesmata-located protein 5 to regulate cell-to-cell movement
Abstract

Numerous cell surface receptors and receptor-like proteins (RLPs) undergo activation or deactivation via a transmembrane domain (TMD). A subset of plant RLPs distinctively localizes to the plasma membrane-lined pores called plasmodesmata. Those RLPs include theArabidopsis thalianaPlasmodesmata-located protein (PDLP) 5, which is well known for its vital function regulating plasmodesmal gating and molecular movement between cells. In this study, we report that the TMD, although not a determining factor for the plasmodesmal targeting, serves essential roles for the PDLP5 function. In addition to its role for membrane anchoring, the TMD mediates PDLP5 self-interaction and carries an evolutionarily conserved motif that is essential for PDLP5 to regulate cell-to-cell movement. Computational modeling-based analyses suggest that PDLP TMDs have high propensities to dimerize. We discuss how a specific mode(s) of TMD dimerization might serve as a common mechanism for PDLP5 and other PDLP members to regulate cell-to-cell movement.

Authors:
; ; ;
Award ID(s):
1820103
Publication Date:
NSF-PAR ID:
10159086
Journal Name:
Communications Biology
Volume:
3
Issue:
1
ISSN:
2399-3642
Publisher:
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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