中图分类号：S562：Q786 文献标识号：A 文章编号：1001-4942（2025）06-0001-14

AbstractR2R3-MYB transcription factors play crucial roles in the process of plants responding to stress. In this study，based on the genomic data of Gosspium barbadense，the members of the R2R3-MYB gene family in G .barbadense were systematically identified. Bioinformatics methods were used to analyze the phyletic evolution，structure，physicochemical properties，and cis-acting elements of the promoter of the R2R3-MYB gene family in G . barbadense. Five candidate genes for Verticillium wilt resistance were screened out using transcriptome expression profiles，and the expression patterns of each candidate gene under the induction of Verticillium wilt，salicylic acid （SA）and methyl jasmonate （MeJA） were analyzed by real-time fluorescence quantitative PCR. The results showed that there were 98 R2R3-MYB genes in the genome of G .barbadense，which distributed on 25 chromosomes.The phylogenetic tree analysis indicated that the members of the R2R3-MYB gene family in G. barbadense could be divided into three large subgroups，and they were relatively conserved in evolution.Promoter analysis revealed multiple cis-acting elements related to plant hormonesand stress responses.The expression patern analysis after Verticillium wilt stress showed that all the R2R3-MYB genes in G barbadense had different degrees of diferential expression after Verticillium wilt stress.Five candidate genes for Verticillium wilt resistance in G. barbadense （GbMYB-21，GbMYB-34，GbMYB-39， GbMYB-76，and GbMYB83）were screened out，which were all induced by Verticillum wilt stress，SA and MeJA.In conclusion，this study demonstrated that the R2R3-MYB gene family in G. barbadense played an important role in coton disease resistance，which could provide a theoretical basis for further research on the functions of R2R3-MYB genes in G. barbadense and the molecular mechanism of cotton resistance to Verticillium wilt.

KeywordsGossypium barbadense； R2R3-MYB gene family； Bioinformatics analysis； Verticillium wiltstress ； Expression analysis

棉花是我国重要的经济作物，在纺织、国防、医药和汽车等领域有着重要的用途。然而随着棉花种植面积的扩大以及连年种植，黄萎病危害越发严重，造成棉花产量的损失。由于缺乏可利用的抗性资源且棉花抗黄萎病的分子机制尚不清晰，使棉花抗黄萎病育种成为世界性难题。海岛棉具有较高的黄萎病抗性，因此解析海岛棉抗黄萎病的分子机制成为了一个热门且亟需解决的问题。

转录因子又称反式作用因子，通过与真核基因的顺式作用元件产生特异性相互作用激活或抑制基因的转录[1]。MYB是植物中一类最大的转录因子家族，第一个MYB转录因子是从玉米中分离鉴定出来的 ZmMYBC1^[2] 。基于其N端所包含的MYB保守结构域的数目将MYB蛋白归于4个亚类：1R-MYB（R1/2或R3MYB）、2R-MYB（R2R3-MYB）3R-MYB（R1R2R3-MYB）和4R-MYB（R1/R2-like）[3]。每个MYB 保守结构域均由50个左右氨基酸组成并编码3个a螺旋，形成螺旋-转角-螺旋结构嵌合在DNA大沟中，而在MYB蛋白的C端通常包含1个转录激活域或1个发挥转录抑制功能的EAR结构[4]。这4个亚类的MYB蛋白在功能上存在巨大的差异，其中1R蛋白参与次生代谢、响应磷饥饿信号以及花与果实的发育调控[5];3R蛋白通常与细胞周期的调控紧密相关[；4R蛋白是最小的一个亚类，目前尚无功能报道;2R蛋白是成员最多的一个亚类，根据其C端保守氨基酸结构域分为28个亚组，分别参与初生代谢和次生代谢、激素信号传导、发育调控及生物逆境胁迫和非生物逆境胁迫响应等[7-8]

R2R3-MYB转录因子在植物抗病过程中发挥着重要作用。……