Yuan Wenya, Yao Fengge, Liu Yijing, Xiao Hongci, Sun Siheng, Jiang Cheng, An Yi, Chen Ningning, Huang Lichao, Lu Mengzhu, Zhang Jin
State Key Laboratory of Subtropical Silviculture, College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, Zhejiang, China.
For Res (Fayettev). 2024 Dec 31;4:e039. doi: 10.48130/forres-0024-0036. eCollection 2024.
The xyloglucan endotransglycosylase/hydrolase (XTH) gene family plays a crucial role in plant cell wall remodeling, facilitating growth and structural changes. However, the divergence of paralogous genes among different species of remains inadequately understood. This study investigates the phylogenetic relationships and expression characteristics of genes in two species: and '84K'. Forty-one were identified in and 38 and 33 members in the subgenome A and G of '84K' poplar, respectively. Gene expression analysis demonstrated differences among paralogous genes within the same subgenome and between orthologous genes across species, likely influenced by variations in promoter regions. Notably, showed a specific response to drought stress among various abiotic stresses. In a population of 549 individuals, functional SNPs in 's coding region did not affect its conserved ExDxE catalytic site, highlighting its irreplaceable function. Furthermore, validation through qRT-PCR and activity, alongside -overexpression poplar lines, substantiated the role of PagXTH12 in modulating the balance between plant biomass and drought resistance. Overall, this research provides valuable insights into the biological functions of XTHs in plant environmental adaptability and offers strategies for targeted regulation of tree growth and stress resistance.
木葡聚糖内转糖基酶/水解酶（XTH）基因家族在植物细胞壁重塑中起着关键作用，促进植物生长和结构变化。然而，不同物种间旁系同源基因的分化仍未得到充分了解。本研究调查了两个杨树物种（毛果杨和‘84K’杨）中XTH基因的系统发育关系和表达特征。在毛果杨中鉴定出41个XTH基因，在‘84K’杨的A和G亚基因组中分别鉴定出38个和33个成员。基因表达分析表明，同一亚基因组内的旁系同源基因以及不同物种间的直系同源基因存在差异，这可能受启动子区域变异的影响。值得注意的是，在各种非生物胁迫中，XTH基因对干旱胁迫表现出特异性响应。在一个由549株毛果杨个体组成的群体中，毛果杨编码区的功能性单核苷酸多态性（SNP）并未影响其保守的ExDxE催化位点，突出了其不可替代的功能。此外，通过qRT-PCR和XTH活性验证以及XTH过表达杨树株系，证实了PagXTH12在调节植物生物量和抗旱性平衡中的作用。总体而言，本研究为XTH基因在植物环境适应性中的生物学功能提供了有价值的见解，并为树木生长和抗逆性的靶向调控提供了策略。
