The myeloblastosis (MYB) family comprises a large group of transcription factors (TFs) that has a variety of functions. Among them, the R2R3-MYB type of proteins are the largest group in plants, which are involved in controlling various biological processes such as plant growth and development, physiological metabolism, defense, and responses to abiotic and biotic stresses. In this study, bioinformatics was adopted to conduct genome-wide identification of the R2R3-MYB TFs in rice. We identified 190 MYB TFs (99 R2R3-MYBs), which are unevenly distributed on the 12 chromosomes of rice. Based on the phylogenetic clustering and protein sequence characteristics, OsMYBs were classified into five subgroups, and 59.6% of the Os2R_MYB genes contained two introns. Analysis of cis-acting elements in the 2000 bp upstream region of Os2R_MYB genes showed that all Os2R_MYB genes contained plant hormones-related or stress-responsive elements since 91.9%, 79.8%, 79.8%, and 58.6% of Os2R_MYB genes contain ABRE, TGACG, CGTCA, and MBS motifs, respectively. Protein–protein network analysis showed that the Os2R_MYBs were involved in metabolic process, biosynthetic process, and tissue development. In addition, some genes showed a tissue-specific or developmental-stage-specific expression pattern. Moreover, the transcription levels of 20 Os2R_MYB genes under polyethylene glycol (PEG) and cadmium chloride (CdCl₂) stress inducers were dissected by qRT-PCR. The results indicated genes with an altered expression upon PEG or CdCl₂ stress induction. These results potentially supply a basis for further research on the role that Os2R_MYB genes play in plant development and stress responses.

中文翻译：

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水稻非生物胁迫下R2R3-MYB转录因子的全基因组鉴定及表达分析

成髓细胞增多症 (MYB) 家族包含一大群具有多种功能的转录因子 (TF)。其中，R2R3-MYB型蛋白质是植物中最大的一类，参与控制植物生长发育、生理代谢、防御以及对非生物和生物胁迫的反应等多种生物过程。本研究采用生物信息学方法对水稻中的 R2R3-MYB 转录因子进行全基因组鉴定。我们鉴定了 190 个 MYB TF（99 个 R2R3-MYB），它们不均匀地分布在水稻的 12 条染色体上。根据系统发育聚类和蛋白质序列特征，将 OsMYB 分为 5 个亚群，其中 59.6% 的Os2R_MYB基因包含两个内含子。Os2R_MYB基因上游2000 bp区域顺式作用元件分析表明，所有Os2R_MYB基因都含有植物激素相关或胁迫响应元件，因为91.9%、79.8%、79.8%和58.6%的Os2R_MYB基因含有ABRE、TGACG 、CGTCA 和 MBS 基序。蛋白质-蛋白质网络分析表明，Os2R_MYBs参与了代谢过程、生物合成过程和组织发育。此外，一些基因表现出组织特异性或发育阶段特异性表达模式。此外，20 个Os2R_MYB基因在聚乙二醇 (PEG) 和氯化镉 (CdCl ₂) 应激诱导物通过 qRT-PCR 进行解剖。结果表明基因在 PEG 或 CdCl ₂应激诱导时表达改变。这些结果可能为进一步研究Os2R_MYB基因在植物发育和胁迫响应中的作用提供基础。