Regulation of secondary cell wall biosynthesis by a NAC transcription factor from Miscanthus
Regulation of secondary cell wall biosynthesis by a NAC transcription factor from Miscanthus
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DOI：
10.1002/pld3.24
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发表时间：
2017-11-01
期刊：
影响因子：
3
通讯作者：
Wolf, Sebastian
中科院分区：
文献类型：
--
作者：
Golfier, Philippe;Volkert, Christopher;Wolf, Sebastian
细胞壁顽抗性是木质纤维素生物质作为可再生资源可持续利用的主要限制。芒属的物种和杂交种已成为温带气候下生产木质纤维素原料的候选作物，并且正在努力提高生物量产量。然而，对于参与芒草细胞壁生物合成以促进针对定制生物量的育种工作的分子参与者一无所知。在这里，我们鉴定了与次生壁相关NAC域1（SND1）相关的芒草转录因子，其充当调节次生细胞壁形成和木质素生物合成的主开关。 MsSND1 在与次生细胞壁形成相关的生长阶段及其潜在靶标表达。与这一观察结果一致，MsSND1能够补充拟南芥snd1 nst1双突变体的次生细胞壁缺陷，并且MsSND1在烟草叶中的异位表达足以触发纤维素、半纤维素和木质素的图案化沉积，让人想起木质部元素。拟南芥植物转基因研究表明，MsSND1 直接和间接调节涉及次生细胞壁形成的多种基因的表达，包括仅调节 SCW 分化程序的子集的 MYB 转录因子。总之，我们的研究结果表明，MsSND1 是芒草中协调次生细胞壁生物合成的转录主调节因子。
Cell wall recalcitrance is a major limitation for the sustainable exploitation of lignocellulosic biomass as a renewable resource. Species and hybrids of the genus Miscanthus have emerged as candidate crops for the production of lignocellulosic feedstock in temperate climates, and dedicated efforts are underway to improve biomass yield. However, nothing is known about the molecular players involved in Miscanthus cell wall biosynthesis to facilitate breeding efforts towards tailored biomass. Here, we identify a Miscanthus sinensis transcription factor related to SECONDARY WALL-ASSOCIATED NAC DOMAIN1 (SND1), which acts as a master switch for the regulation of secondary cell wall formation and lignin biosynthesis. MsSND1 is expressed in growth stages associated with secondary cell wall formation, together with its potential targets. Consistent with this observation, MsSND1 was able to complement the secondary cell wall defects of the Arabidopsis snd1 nst1 double mutant, and ectopic expression of MsSND1 in tobacco leaves was sufficient to trigger patterned deposition of cellulose, hemicellulose, and lignin reminiscent of xylem elements. Transgenic studies in Arabidopsis thaliana plants revealed that MsSND1 regulates, directly and indirectly, the expression of a broad range of genes involved in secondary cell wall formation, including MYB transcription factors which regulate only a subset of the SCW differentiation program. Together, our findings suggest that MsSND1 is a transcriptional master regulator orchestrating secondary cell wall biosynthesis in Miscanthus.