Wang Yi-Ming, Yang Qi, Liu Yan-Jing, Yang Hai-Ling
Department of Biochemistry and Molecular Biology, College of Biological Sciences and Biotechnology, Beijing Forestry University Beijing, China.
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences Beijing, China.
Front Plant Sci. 2016 Dec 12;7:1879. doi: 10.3389/fpls.2016.01879. eCollection 2016.
Aconitase (ACO) is a key enzyme that catalyzes the isomerization of citrate to isocitrate in the tricarboxylic acid (TCA) and glyoxylate cycles. The function of ACOs has been well studied in model plants, such as . In contrast, the evolutionary patterns of the ACO family in land plants are poorly understood. In this study, we systematically examined the molecular evolution and expression divergence of the ACO gene family in 12 land plant species. Thirty-six ACO genes were identified from the 12 land plant species representing the four major land plant lineages: Bryophytes, lycophytes, gymnosperms, and angiosperms. All of these ACOs belong to the cytosolic isoform. Three gene duplication events contributed to the expansion of the ACO family in angiosperms. The ancestor of angiosperms may have contained only one ACO gene. One gene duplication event split angiosperm ACOs into two distinct clades. Two clades showed a divergence in selective pressure and gene expression patterns. The -acting elements that function in light responsiveness were most abundant in the promoter region of the ACO genes, indicating that plant ACO genes might participate in light regulatory pathways. Our findings provide comprehensive insights into the ACO gene family in land plants.
乌头酸酶（ACO）是一种关键酶，它在三羧酸（TCA）循环和乙醛酸循环中催化柠檬酸异构化为异柠檬酸。ACO在模式植物（如……）中的功能已得到充分研究。相比之下，陆地植物中ACO家族的进化模式却知之甚少。在本研究中，我们系统地研究了12种陆地植物物种中ACO基因家族的分子进化和表达差异。从代表四大陆地植物谱系（苔藓植物、石松植物、裸子植物和被子植物）的12种陆地植物物种中鉴定出36个ACO基因。所有这些ACO都属于胞质异构体。三次基因复制事件促成了ACO家族在被子植物中的扩张。被子植物的祖先可能仅含有一个ACO基因。一次基因复制事件将被子植物的ACO分为两个不同的分支。两个分支在选择压力和基因表达模式上存在差异。在ACO基因启动子区域中，参与光响应的顺式作用元件最为丰富，这表明植物ACO基因可能参与光调节途径。我们的研究结果为陆地植物中的ACO基因家族提供了全面的见解。
