Department of Biology, Syracuse University, Syracuse, NY, 13244, USA.
Sci Rep. 2024 Jun 1;14(1):12592. doi: 10.1038/s41598-024-63408-x.
The plant cell wall serves as a critical interface between the plant and its environment, offering protection against various stresses and contributing to biomass production. Hemicellulose is one of the major components of the cell wall, and understanding the transcriptional regulation of its production is essential to fully understanding cell wall formation. This study explores the regulatory mechanisms underlying one of the genes involved in hemicellulose biosynthesis, PtrPARVUS2. Six transcription factors (TFs) were identified from a xylem-biased library to negatively regulate PtrPARVUS2 expression. These TFs, belonging to diverse TF families, were confirmed to bind to specific cis-elements in the PtrPARVUS2 promoter region, as validated by Yeast One-Hybrid (Y1H) assays, transient expression analysis, and Chromatin Immunoprecipitation sequencing (ChIP-seq) assays. Furthermore, motif analysis identified putative cis-regulatory elements bound by these TFs, shedding light on the transcriptional regulation of SCW biosynthesis genes. Notably, several TFs targeted genes encoding uridine diphosphate glycosyltransferases (UGTs), crucial enzymes involved in hemicellulose glycosylation. Phylogenetic analysis of UGTs regulated by these TFs highlighted their diverse roles in modulating hemicellulose synthesis. Overall, this study identifies a set of TFs that regulate PARVUS2 in poplar, providing insights into the intricate coordination of TFs and PtrPARVUS2 in SCW formation. Understanding these regulatory mechanisms enhances our ability to engineer plant biomass for tailored applications, including biofuel production and bioproduct development.
植物细胞壁作为植物与其环境之间的关键界面，提供了对各种胁迫的保护，并有助于生物质的产生。半纤维素是细胞壁的主要成分之一，了解其生物合成的转录调控对于全面理解细胞壁的形成至关重要。本研究探讨了参与半纤维素生物合成的基因之一 PtrPARVUS2 的调控机制。从木质部偏向文库中鉴定出 6 个转录因子（TFs），它们负调控 PtrPARVUS2 的表达。这些 TF 属于不同的 TF 家族，通过酵母单杂交（Y1H）分析、瞬时表达分析和染色质免疫沉淀测序（ChIP-seq）分析证实它们可以结合 PtrPARVUS2 启动子区域的特定顺式元件。此外， motif 分析鉴定出这些 TF 结合的潜在顺式调控元件，揭示了 SCW 生物合成基因的转录调控。值得注意的是，一些 TF 靶向编码尿苷二磷酸糖基转移酶（UGTs）的基因，UGTs 是参与半纤维素糖基化的关键酶。受这些 TF 调控的 UGTs 的系统发育分析突出了它们在调节半纤维素合成中的多样化作用。总的来说，本研究鉴定了一组在杨树中调控 PARVUS2 的 TF，为深入了解 TF 和 PtrPARVUS2 在 SCW 形成中的复杂协调提供了线索。理解这些调控机制提高了我们为特定应用工程植物生物质的能力，包括生物燃料生产和生物制品开发。
