Chemical and Transcriptomic Analysis of Cuticle Lipids under Cold Stress in Thellungiella salsuginea

Abstract

Plant cuticle lipids form outer protective layers to resist environmental stresses; however, the relationship between cuticle properties and cold tolerance is unclear. Here, the extremophyte Thellungiella salsuginea was stressed under cold conditions (4 °C) and the cuticle of rosette leaves was examined in terms of epicuticular wax crystal morphology, chemical composition, and cuticle-associated gene expression. The results show that cold induced formation of distinct lamellas within the cuticle ultrastructure. Cold stress caused 14.58% and 12.04% increases in the amount of total waxes and cutin monomer per unit of leaf area, respectively, probably associated with the increase in total fatty acids. The transcriptomic analysis was performed on rosette leaves of Thellungiella exposed to cold for 24 h. We analyzed the expression of 72 genes putatively involved in cuticle lipid metabolism, some of which were validated by qRT-PCR (quantitative reverse transcription PCR) after both 24 h and one week of cold exposure. Most cuticle-associated genes exhibited higher expression levels under cold conditions, and some key genes increased more dramatically over the one week than after just 24 h, which could be associated with increased amounts of some cuticle components. These results demonstrate that the cuticle provides some aspects of cold adaptation in T. salsuginea.

An Advanced Lipid Metabolism System Revealed by Transcriptomic and Lipidomic Analyses Plays a Central Role in Peanut Cold Tolerance

“…Interestingly, KCS1 and KCS6, which are mainly responsible for the synthesis of fatty acids above 24 carbon chain length and involved in cutin, suberine, and wax biosynthesis, catalyze the first step of fatty acid elongation, and were extremely significantly downregulated in NH5 (Hooker et al, 2002). Wax is the first barrier to plant contact with the external environment and plays an important role in adaptation to sudden variations in environmental conditions (Xue et al, 2017;He et al, 2019). The relationship between wax secretion and peanut cold tolerance deserves further study.…”

Environment-Driven Adaptations of Leaf Cuticular Waxes Are Inheritable for Medicago ruthenica

“…This further validated that M. ruthenica would alter the leaf wax deposition when facing climate changes, which contributed to their improved stress adaptations (Shepherd et al, 1997;Gordon et al, 1998;Kosma et al, 2009). During the last two decades, great achievements have been obtained in understanding the responses to leaf cuticular wax to environmental stresses like drought (Kosma et al, 2009), cold (He et al, 2019), light (Giese, 1975), enhanced UVB (Pilon et al, 1999), and high temperature (Shepherd et al, 1997). To test how much the environment factors contribute to such variations of cuticular waxes among M. ruthenica populations, Pearson' correlation analysis and redundancy analysis were applied.…”

Transcriptomic analysis of Vigna radiata in response to chilling stress and uniconazole application

“…The plant cuticle is the first protective barrier against environmental stress. Most cuticle-associated genes, including those involved in cuticle lipid synthesis, export of cuticular lipids, and regulation of plant cuticle development, are upregulated under low-temperature treatment [ 44 ]. In our experiment, most of these genes were downregulated after chilling stress with or without UNZ application, but UNZ treatment effectively prevented further downregulation of the expression of these genes.…”