Hoffmann Danielle Yvonne, Shachar-Hill Yair
Department of Plant Biology, Michigan State University, East Lansing, MI, United States.
Front Plant Sci. 2023 Jan 19;14:1077347. doi: 10.3389/fpls.2023.1077347. eCollection 2023.
Acyl editing refers to a deacylation and reacylation cycle on a lipid, which allows for fatty acid desaturation and modification prior to being removed and incorporated into other pools. Acyl editing is an important determinant of glycerolipid synthesis and has been well-characterized in land plants, thus this review begins with an overview of acyl editing in plants. Much less is known about acyl editing in algae, including the extent to which acyl editing impacts lipid synthesis and on which lipid substrate(s) it occurs. This review compares what is known about acyl editing on its major hub phosphatidylcholine (PC) in land plants with the evidence for acyl editing of betaine lipids such as diacylglyceryltrimethylhomoserine (DGTS), the structural analog that replaces PC in several species of microalgae. In land plants, PC is also known to be a major source of fatty acids and diacylglycerol (DAG) for synthesis of the neutral lipid triacylglycerol (TAG). We review the evidence that DGTS contributes substantially to TAG accumulation in algae as a source of fatty acids, but not as a precursor to DAG. We conclude with evidence of acyl editing on other membrane lipid substrates in plants and algae apart from PC or DGTS, and discuss future analyses to elucidate the role of DGTS and other betaine lipids in acyl editing in microalgae.
酰基编辑是指脂质上的脱酰基和再酰基化循环,它使得脂肪酸在被移除并整合到其他库之前能够进行去饱和及修饰。酰基编辑是甘油脂质合成的一个重要决定因素,并且在陆地植物中已得到充分研究,因此本综述首先概述植物中的酰基编辑。相比之下,关于藻类中的酰基编辑我们了解得要少得多,包括酰基编辑对脂质合成的影响程度以及它发生在哪种脂质底物上。本综述将陆地植物中关于其主要枢纽磷脂酰胆碱(PC)的酰基编辑的已知信息与甜菜碱脂质(如二酰甘油基三甲基高丝氨酸,DGTS)的酰基编辑证据进行了比较,DGTS是在几种微藻中取代PC的结构类似物。在陆地植物中,PC也是合成中性脂质三酰甘油(TAG)的脂肪酸和二酰甘油(DAG)的主要来源。我们综述了相关证据,即DGTS作为脂肪酸来源对藻类中TAG积累有显著贡献,但并非作为DAG的前体。我们最后给出了除PC或DGTS之外,植物和藻类中其他膜脂质底物上酰基编辑的证据,并讨论了未来的分析方向,以阐明DGTS和其他甜菜碱脂质在微藻酰基编辑中的作用。