State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
College of Forestry, Northwest A&F University, Yangling 712100, China.
Plant Sci. 2024 Oct;347:112184. doi: 10.1016/j.plantsci.2024.112184. Epub 2024 Jul 10.
Nervonic acid (C24:1) is a very-long-chain fatty acid that plays an imperative role in human brain development and other health benefits. In plants, 3-ketoacyl-CoA synthase (KCS) is the key rate-limiting enzyme for C24:1 biosynthesis. Xanthoceras sorbifolium is a valuable oil-producing economic woody species with abundant C24:1 in seed oils, but the key KCS gene responsible for C24:1 accumulation remains unknown. In this work, a correlation analysis between the transcript profiles of KCS and dynamic change of C24:1 content in developing seeds of X. sorbifolium were conducted to screen out three members of KCS, namely XsKCS4, XsKCS7 and XsKCS8, potentially involved in C24:1 biosynthesis. Of which, the XsKCS7 was highly expressed in developing seeds, while XsKCS4 and XsKCS8 displayed the highest expression in fruits and flowers, respectively. Overexpression of XsKCS4, XsKCS7 and XsKCS8 in yeast Saccharomyces cerevisiae and plant Arabidopsis thaliana indicated that only XsKCS7 possessed the ability to facilitate the biosynthesis of C24:1. These findings collectively suggested that XsKCS7 played a crucial role in specific regulation of C24:1 biosynthesis in X. sorbifolium seeds.
神经酸（C24:1）是一种超长链脂肪酸，在人类大脑发育和其他健康益处中起着至关重要的作用。在植物中，3-酮酰基辅酶 A 合酶（KCS）是 C24:1 生物合成的关键限速酶。文冠果是一种具有丰富 C24:1 的宝贵产油经济木本物种，但其负责 C24:1 积累的关键 KCS 基因尚不清楚。在这项工作中，对文冠果发育种子中 KCS 的转录谱与 C24:1 含量的动态变化之间的相关性分析，筛选出三个可能参与 C24:1 生物合成的 KCS 成员，即 XsKCS4、XsKCS7 和 XsKCS8。其中，XsKCS7 在发育种子中高度表达，而 XsKCS4 和 XsKCS8 分别在果实和花朵中表达最高。XsKCS4、XsKCS7 和 XsKCS8 在酵母酿酒酵母和植物拟南芥中的过表达表明，只有 XsKCS7 具有促进 C24:1 生物合成的能力。这些发现共同表明，XsKCS7 在文冠果种子中 C24:1 生物合成的特定调节中起着关键作用。
