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Title: Golgi‐localized MORN1 promotes lipid droplet abundance and enhances tolerance to multiple stresses in Arabidopsis
Abstract

Lipid droplet (LD) in vegetative tissues has recently been implicated in environmental responses in plants, but its regulation and its function in stress tolerance are not well understood. Here, we identified aMembrane Occupation and Recognition Nexus 1(MORN1) gene as a contributor to natural variations of stress tolerance through genome‐wide association study inArabidopsis thaliana. Characterization of its loss‐of‐function mutant and natural variants revealed that theMORN1gene is a positive regulator of plant growth, disease resistance, cold tolerance, and heat tolerance. The MORN1 protein is associated with the Golgi and is also partly associated with LD. Protein truncations that disrupt these associations abolished the biological function of the MORN1 protein. Furthermore, theMORN1gene is a positive regulator of LD abundance, and its role in LD number regulation and stress tolerance is highly linked. Therefore, this study identifies MORN1 as a positive regulator of LD abundance and a contributor to natural variations of stress tolerance. It implicates a potential involvement of Golgi in LD biogenesis and strongly suggests a contribution of LD to diverse processes of plant growth and stress responses.

 
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Award ID(s):
1946174
NSF-PAR ID:
10422251
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of Integrative Plant Biology
Volume:
65
Issue:
8
ISSN:
1672-9072
Page Range / eLocation ID:
p. 1890-1903
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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