Claver Ana, Luján María Ángeles, Escuín José Manuel, Schilling Marion, Jouhet Juliette, Savirón María, López M Victoria, Picorel Rafael, Jarne Carmen, Cebolla Vicente L, Alfonso Miguel
Department of Plant Biology, Estación Experimental Aula Dei-Consejo Superior de Investigaciones Científicas (EEAD-CSIC), Zaragoza, Spain.
Instituto de Carboquímica-Consejo Superior de Investigaciones Científicas (ICB-CSIC), Zaragoza, Spain.
Front Plant Sci. 2024 Apr 26;15:1386023. doi: 10.3389/fpls.2024.1386023. eCollection 2024.
(Pennycress) is an emerging feedstock for biofuel production because of its high seed oil content enriched in erucic acid. A transcriptomic and a lipidomic study were performed to analyze the dynamics of gene expression, glycerolipid content and acyl-group distribution during seed maturation. Genes involved in fatty acid biosynthesis were expressed at the early stages of seed maturation. Genes encoding enzymes of the Kennedy pathway like diacylglycerol acyltransferase1 (, lysophosphatidic acid acyltransferase ( or glycerol 3-phosphate acyltransferase ( increased their expression with maturation, coinciding with the increase in triacylglycerol species containing 22:1. Positional analysis showed that the most abundant triacylglycerol species contained 18:2 at position in all maturation stages, suggesting no specificity of the lysophosphatidic acid acyltransferase for very long chain fatty acids. Diacylglycerol acyltransferase2 ( mRNA was more abundant at the initial maturation stages, coincident with the rapid incorporation of 22:1 to triacylglycerol, suggesting a coordination between Diacylglycerol acyltransferase enzymes for triacylglycerol biosynthesis. Genes encoding the phospholipid-diacylglycerol acyltransferase (PDAT1), lysophosphatidylcholine acyltransferase (LPCAT) or phosphatidylcholine diacylglycerolcholine phosphotransferase (PDCT), involved in acyl-editing or phosphatidyl-choline (PC)-derived diacylglycerol (DAG) biosynthesis showed also higher expression at the early maturation stages, coinciding with a higher proportion of triacylglycerol containing C18 fatty acids. These results suggested a higher contribution of these two pathways at the early stages of seed maturation. Lipidomic analysis of the content and acyl-group distribution of diacylglycerol and phosphatidyl-choline pools was compatible with the acyl content in triacylglycerol at the different maturation stages. Our data point to a model in which a strong temporal coordination between pathways and isoforms in each pathway, both at the expression and acyl-group incorporation, contribute to high erucic triacylglycerol accumulation in Pennycress.
（冬油菜）因其富含芥酸的高种子油含量，正成为生物燃料生产的新兴原料。进行了转录组学和脂质组学研究，以分析种子成熟过程中基因表达、甘油脂含量和酰基分布的动态变化。参与脂肪酸生物合成的基因在种子成熟早期表达。编码肯尼迪途径酶的基因，如二酰甘油酰基转移酶1（、溶血磷脂酸酰基转移酶（或甘油3-磷酸酰基转移酶（，随着成熟而增加其表达，这与含有22:1的三酰甘油种类的增加相吻合。位置分析表明，在所有成熟阶段，最丰富的三酰甘油种类在位置上含有18:2，这表明溶血磷脂酸酰基转移酶对超长链脂肪酸没有特异性。二酰甘油酰基转移酶2（mRNA在成熟初期更为丰富，这与22:1快速掺入三酰甘油相吻合，表明二酰甘油酰基转移酶在三酰甘油生物合成中存在协调作用。编码参与酰基编辑或磷脂酰胆碱（PC）衍生二酰甘油（DAG）生物合成的磷脂-二酰甘油酰基转移酶（PDAT1）、溶血磷脂酰胆碱酰基转移酶（LPCAT）或磷脂酰胆碱二酰甘油胆碱磷酸转移酶（PDCT）的基因，在成熟早期也表现出较高的表达，这与含有C18脂肪酸的三酰甘油比例较高相吻合。这些结果表明这两条途径在种子成熟早期的贡献更大。对二酰甘油和磷脂酰胆碱库的含量和酰基分布进行的脂质组学分析与不同成熟阶段三酰甘油中的酰基含量相符。我们的数据指向一个模型，其中各途径之间以及每个途径中的同工型在表达和酰基掺入方面都存在强烈的时间协调，这有助于冬油菜中高芥酸三酰甘油的积累。
