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Title: All members of the Arabidopsis DGAT and PDAT acyltransferase families operate during high and low temperatures
The accumulation of triacylglycerol (TAG) in vegetative tissues is necessary to adapt to changing temperatures. It has been hypothesized that TAG accumulation is required as a storage location for maladaptive membrane lipids. The TAG acyltransferase family has five members (DIACYLGLYCEROL ACYLTRANSFERSE1/2/3 and PHOSPHOLIPID:DIACYLGLYCEROL ACYLTRANSFERASE1/2), and their individual roles during temperature challenges have either been described conflictingly or not at all. Therefore, we used Arabidopsis (Arabidopsis thaliana) loss of function mutants in each acyltransferase to investigate the effects of temperature challenge on TAG accumulation, plasma membrane integrity, and temperature tolerance. All mutants were tested under one high- and two low-temperature regimens, during which we quantified lipids, assessed temperature sensitivity, and measured plasma membrane electrolyte leakage. Our findings revealed reduced effectiveness in TAG production during at least one temperature regimen for all acyltransferase mutants compared to the wild type, resolved conflicting roles of pdat1 and dgat1 by demonstrating their distinct temperature-specific actions, and uncovered that plasma membrane integrity and TAG accumulation do not always coincide, suggesting a multifaceted role of TAG beyond its conventional lipid reservoir function during temperature stress.  more » « less
Award ID(s):
1845175
PAR ID:
10520802
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Oxford Academic
Date Published:
Journal Name:
Plant Physiology
Volume:
195
Issue:
1
ISSN:
0032-0889
Page Range / eLocation ID:
685 to 697
Subject(s) / Keyword(s):
Dynamic Membranes DGAT PDAT acyltransferases TAG cold heat abiotic stress enzyme family
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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