Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
Int J Mol Sci. 2022 Feb 14;23(4):2079. doi: 10.3390/ijms23042079.
In vascular plants, the importance of R2R3-myeloblastosis (R2R3-MYB) transcription factors (TFs) in the formation of secondary cell walls (SCWs) has long been a controversial topic due to the lack of empirical evidence of an association between TFs and downstream target genes. Here, we found that the transcription factor , which belongs to the R2R3-MYB subfamily, is involved in lignin biosynthesis in . was highly expressed in lignified tissues and upon abiotic stress. As a bait carrier, the PmMYB7 protein had no toxicity or autoactivation in the nucleus. Forty-seven proteins were screened from the yeast library. These proteins were predicted to be mainly involved in resistance, abiotic stress, cell wall biosynthesis, and cell development. We found that the PmMYB7 protein interacted with caffeoyl CoA 3-O-methyltransferase-2 (PmCCoAOMT2)-which is involved in lignin biosynthesis-but not with beta-1, 2-xylosyltransferase (PmXYXT1) yeast two-hybrid (Y2H) studies. Our in vivo coimmunoprecipitation (Co-IP) assay further showed that the PmMYB7 and PmCCoAOMT2 proteins could interact. Therefore, we concluded that is an upstream TF that can interact with PmCCoAOMT2 in plant cells. These findings lay a foundation for further research on the function of , lignin biosynthesis and molecular breeding in
在维管植物中，R2R3-MYB（R2R3-髓细胞白血病）转录因子（TFs）在次生细胞壁（SCWs）形成中的重要性一直是一个有争议的话题，因为缺乏 TFs 与下游靶基因之间关联的经验证据。在这里，我们发现属于 R2R3-MYB 亚家族的转录因子 参与了 的木质素生物合成。 在木质化组织和非生物胁迫下高度表达。作为诱饵载体，PmMYB7 蛋白在核内没有毒性或自动激活。从 酵母文库中筛选出 47 种蛋白质。这些蛋白质被预测主要参与抵抗、非生物胁迫、细胞壁生物合成和细胞发育。我们发现 PmMYB7 蛋白与咖啡酰辅酶 A 3-O-甲基转移酶-2（PmCCoAOMT2）相互作用-参与木质素生物合成-但不与β-1,2-木糖基转移酶（PmXYXT1）酵母双杂交（Y2H）研究。我们的体内共免疫沉淀（Co-IP）实验进一步表明，PmMYB7 和 PmCCoAOMT2 蛋白可以相互作用。因此，我们得出结论， 是一种可以与植物细胞中的 PmCCoAOMT2 相互作用的上游 TF。这些发现为进一步研究 、木质素生物合成和分子育种在 中的功能奠定了基础。
