Key Laboratory of National Forestry and Grassland Administration for Fast-Growing Tree Breeding and Cultivation in Central and Southern China, College of Forestry, Guangxi University, Nanning 530004, China.
College of Agronomy, Northwest A&F University, Xianyang 712000, China.
Int J Mol Sci. 2023 Aug 4;24(15):12430. doi: 10.3390/ijms241512430.
R2R3-MYB transcription factors (TFs) form one of the most important TF families involved in regulating various physiological functions in plants. The heartwood of is a kind of high-grade mahogany and valuable herbal medicine with wide application. However, the role of R2R3-MYB genes in the growth and development of , especially their relevance to heartwood formation, has not been revealed. A total of 126 R2R3-MYBs were screened from the genome and named DodMYB1-126 based on their location on 10 chromosomes. The collinearity results showed that purification selection was the main driving force for the evolution of the R2R3-MYB TFs family, and whole genome/fragment replication event was the main form for expanding the R2R3-MYB family, generating a divergence of gene structure and function. Comparative phylogenetic analysis classified the R2R3-MYB TFs into 33 subfamilies. S3-7,10,12-13,21 and N4-7 were extensively involved in the metabolic process; S9,13,16-19,24-25 and N1-3,8 were associated with the growth and development of . Based on the differential transcriptional expression levels of R2R3-MYBs in different tissues, DodMYB32, DodMYB55, and DodMYB89 were tentatively screened for involvement in the regulatory process of heartwood. Further studies have shown that the DodMYB89, localized in the nucleus, has transcriptional activation activity and is involved in regulating the biosynthesis of the secondary metabolites of heartwood by activating the promoters of the structural genes and . This study aimed to comprehensively analyze the functions of the R2R3-MYB TFs and screen for candidate genes that might be involved in heartwood formation of .
R2R3-MYB 转录因子（TFs）是参与调控植物各种生理功能的最重要的 TF 家族之一。 的心材是一种高档桃花心木和有价值的草药，应用广泛。然而，R2R3-MYB 基因在 生长和发育中的作用，特别是它们与心材形成的相关性，尚未被揭示。从 基因组中筛选出 126 个 R2R3-MYB，并根据它们在 10 条染色体上的位置命名为 DodMYB1-126。共线性结果表明，纯化选择是 R2R3-MYB TF 家族进化的主要驱动力，而全基因组/片段复制事件是扩展 R2R3-MYB 家族的主要形式，导致基因结构和功能的分化。比较系统发育分析将 R2R3-MYB TFs 分为 33 个亚家族。S3-7、10、12-13、21 和 N4-7 广泛参与代谢过程；S9、13、16-19、24-25 和 N1-3、8 与 的生长和发育有关。基于 R2R3-MYB 在不同组织中的差异转录表达水平，初步筛选 DodMYB32、DodMYB55 和 DodMYB89 参与调控心材的调节过程。进一步的研究表明，定位于核内的 DodMYB89 具有转录激活活性，通过激活结构基因 和 的启动子，参与调控心材次生代谢物的生物合成。本研究旨在全面分析 R2R3-MYB TFs 的功能，并筛选可能参与 心材形成的候选基因。
