The Role of Triacylglycerol in Plant Stress Response

Abstract

Vegetable oil is mainly composed of triacylglycerol (TAG), a storage lipid that serves as a major commodity for food and industrial purposes, as well as an alternative biofuel source. While TAG is typically not produced at significant levels in vegetative tissues, emerging evidence suggests that its accumulation in such tissues may provide one mechanism by which plants cope with abiotic stress. Different types of abiotic stress induce lipid remodeling through the action of specific lipases, which results in various alterations in membrane lipid composition. This response induces the formation of toxic lipid intermediates that cause membrane damage or cell death. However, increased levels of TAG under stress conditions are believed to function, at least in part, as a means of sequestering these toxic lipid intermediates. Moreover, the lipid droplets (LDs) in which TAG is enclosed also function as a subcellular factory to provide binding sites and substrates for the biosynthesis of bioactive compounds that protect against insects and fungi. Though our knowledge concerning the role of TAG in stress tolerance is expanding, many gaps in our understanding of the mechanisms driving these processes are still evident. In this review, we highlight progress that has been made to decipher the role of TAG in plant stress response, and we discuss possible ways in which this information could be utilized to improve crops in the future.

Winter Nights during Summer Time: Stress Physiological Response to Ice and the Facilitation of Freezing Cytorrhysis by Elastic Cell Wall Components in the Leaves of a Nival Species

“…At the same time, the pectin in cell walls may block ice penetration in the opposite direction. Recent studies have revealed that the accumulation of triglyceride plays an important role in abiotic stress response, especially in plant freezing tolerance [ 46 , 47 , 48 ]. The localization of triglyceride in the spongy tissue, where the major ice masses are accommodated, may be related to freezing stress response, and highlights the interaction between the tissue architecture and function.…”

Arabidopsis thaliana EARLY RESPONSIVE TO DEHYDRATION 7 Localizes to Lipid Droplets via Its Senescence Domain

“…While LDs are known to proliferate during various biotic and abiotic stress treatments (reviewed in Xu and Shanklin, 2016;Pyc et al, 2017b;Yang and Benning, 2018;de Vries and Ischebeck, 2020;Lu et al, 2020), the linkage between LDs and stress responses is poorly understood, due in part to the limited numbers of LD-related proteins identified to date. Gene expression studies, on the other hand, have identified numerous genes that are differentially regulated during stress adaptation.…”

Identification, Classification, and Expression Analysis of the Triacylglycerol Lipase (TGL) Gene Family Related to Abiotic Stresses in Tomato

“…The degradation of LD is initiated with the degradation of LD-associated proteins, in which subsequently, peroxisome can interact with the LD and deliver AtSDP1 into the LD surface. TGLs, in association with other lipases, hydrolyzes the TAG into FAs and glycerol [ 25 ]. By predicting the transmem brane domain, we found that 35% and 55% of members in subfamily a and c, respectively.…”