In Arabidopsis, () negatively regulates drought tolerance by interacting with the key autophagy adaptor. However, the biological functions of family genes in other plants remain unknown. In this study, a total number of 11 genes, distributed on 8 chromosomes, were identified in the poplar genome. Phylogenetic analysis indicated that they were classified into 4 groups, and have gone through 2 tandem and 7 segmental duplication events. The structures of genes were highly conserved, with similar characteristics and an N-terminal DUF641 (domain of unknown function 641) domain. Cis-acting element analysis revealed that the promoter regions of genes contained a variety of environmental stress, hormone and light response elements. Quantitative real-time PCR analysis displayed that were constitutively expressed with overlapped but distinct expression patterns, and most of them were induced by salt stress. Further Arabidopsis mutant complementation experiments demonstrated that was a functional homolog of , and functioned as a negative regulator in response to salt stress. Our results provide fundamental information for further mechanism study of family genes in the growth, development and response to salinity stress in wooden plants.

中文翻译：

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杨树组成性胁迫（COST）家族基因的全基因组特征及其对盐胁迫的响应

在拟南芥中，()通过与关键的自噬适配器相互作用来负向调节耐旱性。然而，其他植物中家族基因的生物学功能仍然未知。本研究在杨树基因组中鉴定出共有11个基因，分布在8条染色体上。系统发育分析表明它们分为4个类群，并经历了2次串联重复和7次分段重复事件。基因结构高度保守，具有相似的特征和N端DUF641（未知功能641的结构域）结构域。顺式作用元件分析表明，该基因的启动子区含有多种环境胁迫、激素和光响应元件。实时定量PCR分析显示，组成型表达具有重叠但不同的表达模式，并且大多数是由盐胁迫诱导的。进一步的拟南芥突变体互补实验表明，它是 的功能同源物，并作为响应盐胁迫的负调节因子。我们的研究结果为进一步研究木质植物生长、发育和响应盐胁迫的家族基因机制提供了基础信息。