Elsevier

Progress in Lipid Research

Volume 67, July 2017, Pages 27-37
Progress in Lipid Research

Review
Emerging roles for conjugated sterols in plants

https://doi.org/10.1016/j.plipres.2017.06.002Get rights and content
Under a Creative Commons license
open access

Abstract

In plants, sterols are found in free form (free sterols, FSs) and conjugated as steryl esters (SEs), steryl glycosides (SGs) and acyl steryl glycosides (ASGs). Conjugated sterols are ubiquitously found in plants but their relative contents highly differ among species and their profile may change in response to developmental and environmental cues. SEs play a central role in membrane sterol homeostasis and also represent a storage pool of sterols in particular plant tissues. SGs and ASGs are main components of the plant plasma membrane (PM) that specifically accumulate in lipid rafts, PM microdomains known to mediate many relevant cellular processes. There are increasing evidences supporting the involvement of conjugated sterols in plant stress responses. In spite of this, very little is known about their metabolism. At present, only a limited number of genes encoding enzymes participating in conjugated sterol metabolism have been cloned and characterized in plants. The aim of this review is to update the current knowledge about the tissue and cellular distribution of conjugated sterols in plants and the enzymes involved in their biosynthesis. We also discuss novel aspects on the role of conjugated sterols in plant development and stress responses recently unveiled using forward- and reverse-genetic approaches.

Abbreviations

ASG
acyl steryl glycoside
DIM
detergent-insoluble membrane
ER
endoplasmic reticulum
FS
free sterol
LD
lipid droplet
SE
steryl ester
SG
steryl glycoside
PM
plasma membrane

Keywords

Sterol
Conjugated sterol
Steryl ester
Steryl glycoside
Acyl steryl glycoside

Cited by (0)