He Fang, Shi Yu-Jie, Li Jun-Lin, Lin Tian-Tian, Zhao Kuang-Ji, Chen Liang-Hua, Mi Jia-Xuan, Zhang Fan, Zhong Yu, Lu Meng-Meng, Niu Meng-Xue, Feng Cong-Hua, Ding Shan-Shan, Peng Min-Yue, Huang Jin-Liang, Yang Han-Bo, Wan Xue-Qin
Sichuan Province Key Laboratory of Ecological Forestry Engineering on the Upper Reaches of the Yangtze River, College of Forestry, Sichuan Agricultural University, Chengdu 611130, China.
College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611130, China.
Int J Biol Macromol. 2022 Apr 15;204:76-88. doi: 10.1016/j.ijbiomac.2022.01.202. Epub 2022 Feb 4.
Cadmium, a toxic heavy metal, seriously affects human health and ecological security. The cation/H exchanger (CAX) family is a unique metal transporter that plays a crucial role in Cd acquisition, transfer, and remission in plants. Although there are many studies related to the genome-wide analysis of Populus trichocarpa, little research has been done on the CAX family genes, especially concerning Cd stress. In this study, genome-wide analysis of the Populus CAX family identified seven stress-related CAX genes. The evolutionary tree indicated that the CaCA family genes were grouped into four clusters. Moreover, seven pairs of genes were derived by segmental duplication in poplars. Cis-acting element analysis identified numerous stress-related elements in the promoters of diverse PtrCAXs. Furthermore, some PtrCAXs were up-regulated by drought, beetle, and mechanical damage, indicating their possible function in regulating stress response. Under cadmium stress, all CAX genes in the roots were up-regulated. Our findings suggest that plants may regulate their response to Cd stress through the TF-CAXs module. Comprehensively investigating the CAX family provides a scientific basis for the phytoremediation of heavy metal pollution by Populus.
镉作为一种有毒重金属，严重影响人类健康和生态安全。阳离子/质子交换体（CAX）家族是一类独特的金属转运蛋白，在植物对镉的吸收、转运和解毒过程中发挥着关键作用。尽管已有许多关于毛果杨全基因组分析的研究，但针对CAX家族基因的研究较少，尤其是在镉胁迫方面。在本研究中，对毛果杨CAX家族进行全基因组分析，鉴定出7个与胁迫相关的CAX基因。进化树分析表明，CaCA家族基因被分为4个簇。此外，杨树中通过片段重复产生了7对基因。顺式作用元件分析在不同PtrCAXs基因的启动子中鉴定出大量与胁迫相关的元件。此外，一些PtrCAXs基因受干旱、甲虫侵害和机械损伤诱导上调，表明它们在调节胁迫反应中可能发挥作用。在镉胁迫下，根中所有CAX基因均上调。我们的研究结果表明，植物可能通过TF-CAXs模块调节对镉胁迫的反应。对CAX家族的全面研究为杨树修复重金属污染提供了科学依据。
