PagERF81 regulates lignin biosynthesis and xylem cell differentiation in poplar  

作　　者：Xin-Wei Zhao Qiao Wang Dian Wang Wei Guo Meng-Xuan Hu Ying-Li Liu Gong-Ke Zhou Guo-Hua Chai Shu-Tang Zhao Meng-Zhu Lu 

机构地区：[1]State Key Laboratory of Tree Genetics and Breeding,Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091,China [2]Collegeof Resources and Environment,QingdaoAgricultural University,Qingdao 266109,China [3]CollegeofAgronomy,QingdaoAgriculturalUniversity,Qingdao 266109,China [4]TaishanAcademyof Forestry Sciences,Taian271000,China [5]College of Landscape Architecture and Forestry,Qingdao Agricultural University,Qingdao 266109,China [6]State Key Laboratory of Subtropical Silviculture,College of Forestry and Biotechnology,Zhejiang A&F University,Hangzhou 311300,China

出　　处：《Journal of Integrative Plant Biology》2023年第5期1134-1146,共13页植物学报（英文版）

基　　金：supported by the National Key Scientific Research Project of China (2021YFD2200205);the Ten-Thousand Talents Program of China to Meng-Zhu Lu。

摘　　要：Lignin is a major component of plant cell walls and is essential for plant growth and development. Lignin biosynthesis is controlled by a hierarchical regulatory network involving multiple transcription factors. In this study, we showed that the gene encoding an APETALA 2/ethylene-responsive element binding factor(AP2/ERF) transcription factor, PagERF81,from poplar 84 K(Populus alba × P. glandulosa) is highly expressed in expanding secondary xylem cells. Two independent homozygous Pagerf81 mutant lines created by gene editing, produced significantly more but smaller vessel cells and longer fiber cells with more lignin in cell walls, while PagERF81 overexpression lines had less lignin,compared to non-transgenic controls. Transcriptome and reverse transcription quantitative PCR data revealed that multiple lignin biosynthesis genes including Cinnamoyl CoA reductase 1(PagCCR1),Cinnamyl alcohol dehydrogenase 6(PagCAD6), and 4-Coumarate-CoA ligase-like 9(Pag4CLL9) were upregulated in Pagerf81 mutants, but down-regulated in PagERF81 overexpression lines. In addition, a transient transactivation assay revealed that PagERF81 repressed the transcription of these three genes.Furthermore, yeast one hybrid and electrophoretic mobility shift assays showed that PagERF81 directly bound to a GCC sequence in the PagCCR1 promoter. No known vessel or fiber cell differentiation related genes were differentially expressed, so the smaller vessel cells and longer fiber cells observed in the Pagerf81 lines might be caused by abnormal lignin deposition in the secondary cell walls. This study provides insight into the regulation of lignin biosynthesis, and a molecular tool to engineer wood with high lignin content, which would contribute to the lignin-related chemical industry and carbon sequestration.

关 键 词：lignin biosynthesis PagERF81 POPULUS secondary cell wall xylem development 

分 类 号：S792.11[农业科学—林木遗传育种]