木质素
次生细胞壁
细胞壁
拟南芥
苯丙素
次生代谢
转录因子
化学
MYB公司
生物
拟南芥
生物化学
基因
细胞生物学
转录调控
生物合成
突变体
有机化学
作者
Jianli Zhou,Chanhui Lee,Ruiqin Zhong,Zheng‐Hua Ye
出处
期刊:The Plant Cell
[Oxford University Press]
日期:2009-01-01
卷期号:21 (1): 248-266
被引量:689
标识
DOI:10.1105/tpc.108.063321
摘要
Abstract It has previously been shown that SECONDARY WALL–ASSOCIATED NAC DOMAIN PROTEIN1 (SND1) is a key transcription factor regulating secondary cell wall formation, including the biosynthesis of cellulose, xylan, and lignin. In this study, we show that two closely related SND1-regulated MYB transcription factors, MYB58 and MYB63, are transcriptional regulators specifically activating lignin biosynthetic genes during secondary wall formation in Arabidopsis thaliana. MYB58 and MYB63 are phylogenetically distinct from previously characterized MYBs shown to be associated with secondary wall formation or phenylpropanoid metabolism. Expression studies showed that MYB58 and MYB63 are specifically expressed in fibers and vessels undergoing secondary wall thickening. Dominant repression of their functions led to a reduction in secondary wall thickening and lignin content. Overexpression of MYB58 and MYB63 resulted in specific activation of lignin biosynthetic genes and concomitant ectopic deposition of lignin in cells that are normally unlignified. MYB58 was able to activate directly the expression of lignin biosynthetic genes and a secondary wall–associated laccase (LAC4) gene. Furthermore, the expression of MYB58 and MYB63 was shown to be regulated by the SND1 close homologs NST1, NST2, VND6, and VND7 and their downstream target MYB46. Together, our results indicate that MYB58 and MYB63 are specific transcriptional activators of lignin biosynthesis in the SND1-mediated transcriptional network regulating secondary wall formation.
科研通智能强力驱动
Strongly Powered by AbleSci AI