Adaptation of cuticle metabolism to abiotic stress in plants

Abstract

The cuticle, primarily composed of waxes and cutin polyesters, is a hydrophobic layer that covers the surfaces of plant tissues, evolving as physiological and biochemical adaptations to diverse environments. This layer acts as a diffusion barrier, preventing water loss and protecting plants against various biotic and abiotic stresses. Cuticular lipids, the major constituents of the cuticle, are complex mixtures of fatty acids and their derivatives. The biosynthesis, secretion, and assembly of these lipophilic metabolites are governed by multiple genes and intricately coordinated molecular networks that respond to developmental signals and various environmental stimuli. Advances in plant genetics and analytical techniques have greatly expanded our understanding of the biochemical composition and diverse functions of plant cuticles. This review provides an overview of the cuticle metabolism, with an emphasis on its role in abiotic stress adaptation in crops.

Keywords

Abiotic stress / Cuticle / Cutin / Fatty acids / Lipids / Wax

Abbreviations

ABC ATP binding cassette

ABCG transporters of the G-clade

CER ECERIFERUM

CoA coenzyme A

ECR trans-2-enoyl-CoA reductase

ELO elongase

ER endoplasmic reticulum

FAE fatty acid elongation complex

GPAT glycerol-3-phosphate acyltransferase

HCD β-hydroxyacyl-CoA dehydratase

KCR β-ketoacyl-CoA reductase

KCS β-ketoacyl-CoA synthase

LACS long-chain acyl-coenzyme A synthetase

VLCFA very long-chain fatty acids

Availability of data and materials

Not applicable.

Authors' contributions

Q.L.: Project administration, Conceptualization; P.Z.: Manuscript writing; J.Z., and Q.L.: Manuscript writing, reviewing, and editing; P.Z.: Data analysis; Y.L.: Software; and P.Z. and Q.Q.L.: Data curation.

Declaration of competing interest

The authors declare that they have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This work was supported by the Biological Breeding-National Science and Technology Major Project (2023ZD0407105) and the Fundamental Research Funds for the Central Universities (2662020ZKPY005).

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