Arabidopsis acyl‐CoA‐binding proteins regulate the synthesis of lipid signals

Abstract

Summary Plant lipid signals are crucial developmental modulators and stress response mediators. A family of acyl‐CoA‐binding proteins (ACBPs) participates in the lipid trafficking of these signals. Isoform‐specific functions can arise from differences in their subcellular distribution, tissue‐specificity, stress‐responsiveness, and ligand selectivity. In lipid‐mediated cell signaling, plant ACBPs are not merely transporters but are also important regulators via their interaction with lipid‐metabolic enzymes and precursor lipids. In this Insight, the regulatory roles of plant ACBPs in the synthesis of various signaling lipids, including phosphatidic acid, sterols, oxylipins, and sphingolipids, are reviewed. We focus on the functional significance of these lipid signals in plant development and stress responses with an overview of recent work using reverse genetics and transgenic Arabidopsis.

Sphingolipids: towards an integrated view of metabolism during the plant stress response

“…Hypoxia leads to an increase in ceramides, hydroxyceramides, GlcCers and GIPCs (Xie et al, 2015a,b). In hypoxic conditions, GIPCs are elevated in Arabidopsis and increased further in Atacbp3 (acyl-CoA binding protein 3), whereas AtACBP3-overexpressors were hypersensitive to submergence (Xie et al, 2015b;Lung & Chye, 2019). Similarly, a reduction of unsaturated VLC-ceramides in loh1, loh2 and loh3 mutants due to the disruption of ceramide synthase is accompanied by an enhanced sensitivity to dark submergence.…”

RICE ACYL-COA-BINDING PROTEIN6 Affects Acyl-CoA Homeostasis and Growth in Rice

“…Acyl-CoA esters are not only important intermediates in lipid metabolism but also play a role in regulating multiple cellular processes (Schmidt et al 2018 ; Lung and Chye 2019 ). Recently, direct evidence showed that acyl-CoA esters function in the cellular signaling pathway in Arabidopsis (Schmidt et al 2018 ).…”

“…In plants, ACBPs are highly conserved throughout the evolution of land plants and are divided into four classes (Classes I-IV) based on domain architecture (Meng et al 2011 ). The functions of Arabidopsis ACBPs (AtACBPs) in development and stress responses have been extensively investigated (Du et al 2016 ; Lung and Chye 2016b , 2019 ). Much evidence indicates that AtACBPs mediate multiple aspects of plant physiology by regulating lipid metabolism in Arabidopsis (Du et al 2016 ; Lung and Chye 2016b , 2019 ).…”

“…The functions of Arabidopsis ACBPs (AtACBPs) in development and stress responses have been extensively investigated (Du et al 2016 ; Lung and Chye 2016b , 2019 ). Much evidence indicates that AtACBPs mediate multiple aspects of plant physiology by regulating lipid metabolism in Arabidopsis (Du et al 2016 ; Lung and Chye 2016b , 2019 ). There is only a single 10-kD Class I ACBP member in Arabidopsis, namely AtACBP6, and AtACBP6 has been reported to be a cytosolic protein (Chen et al 2008 ).…”

Crystal structure of the rice acyl‐CoA‐binding protein OsACBP2 in complex with C18:3‐CoA reveals a novel pattern of binding to acyl‐CoA esters

“…ACBPs have been found in all eukaryotes and eleven eubacterial species [2], besides being widely distributed in the plant kingdom [3]. In both Oryza sativa (rice) and Arabidopsis thaliana (thale cress), six ACBPs coexist and they are distributed among four classes (I‐IV) based on their functional domains [3–9]. Class I ACBPs are the smallest (~10 kDa) and contain only an acyl‐CoA‐binding (ACB) domain, while the other classes (II‐IV) of plant ACBPs contain additional domains, including transmembrane domains, kelch motifs and ankyrin repeats [3].…”