文献类型：期刊文献

英文题名：Chemical and Structural Responses to Downregulated p-Hydroxycinnamoyl-Coenzyme A: Quinate/Shikimate p-Hydroxycinnamoyltransferase in Poplar Cell Walls

作者：Su, Minglei[1,2] Liu, Yingli[3] Lyu, Jianxiong[1] Zhao, Shutang[3] Wang, Yurong[1]

第一作者：Su, Minglei

通信作者：Wang, YR[1]|[a0005066e07bcca30717f]王玉荣;

机构：[1]Chinese Acad Forestry, Res Inst Wood Ind, Beijing, Peoples R China;[2]Int Ctr Bamboo & Rattan, Beijing Bamboo & Rattan Sci & Technol, Key Lab Natl Forestry & Grassland Adm, Beijing, Peoples R China;[3]Chinese Acad Forestry, Res Inst Forestry, State Key Lab Tree Genet & Breeding, Beijing, Peoples R China

年份：2022

卷号：12

外文期刊名：FRONTIERS IN PLANT SCIENCE

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000753733400001)】；

基金：This work was funded by the Central Public Interest Scientific Institution Basal Research Fund (CAFYBB2018GD001) and the National Natural Science Foundation of China (31370562).

语种：英文

外文关键词：poplar; HCT; lignin; cell wall components; structural properties

摘要：Unraveling the impact of lignin reduction on cell wall construction of poplar stems is important for accurate understanding the regulatory role of biosynthetic genes. However, few cell-level studies have been conducted on the changes in lignin, other important cell wall composition, and the structural properties of transgenic poplar stems at different developmental stages. In this work, the content and microdistributions of cell wall composition as well as the morphological characteristics of cells were studied for p-hydroxycinnamoyl-coenzyme A:quinate/shikimate p-hydroxycinnamoyltransferase (HCT) downregulated transgenic poplar 84K (Populus alba x P. glandulosa cl. '84k') at different developmental stages. Results show that the lignin contents of the upper, middle, and basal parts of HCT transgenic poplar stems were significantly decreased by 10.84, 7.40, and 7.75%, respectively; and the cellulose contents increased by 8.20, 6.45, and 3.31%, respectively, compared with the control group. The cellulose/lignin ratio of HCT transgenic poplars was therefore increased, especially in the upper sections, where it was 23.2% higher. Raman results indicate the appearance of p-hydroxyphenyl units (H) and a decrease in the ratio of syringyl/guaiacyl (S/G) lignin monomers in fiber cell walls of HCT transgenic poplars. In addition, microstructure observations revealed that the fiber and vessel cells of the HCT transgenic poplars exhibited thin cell walls and large lumen diameters. Compared with the control group, the cell wall thickness of fiber and vessel cells decreased by 6.50 and 10.93% on average, respectively. There was a 13.6% decrease in the average ratio of the cell wall thickness to the lumen diameter and an increase in fiber length and width of 5.60 and 6.11%, respectively. In addition, downregulation of HCT did not change the orientation of cellulosic microfibrils, but it led to an 11.1% increase of the cellulose crystallinity in cell walls compared to the control poplars. The information obtained herein could lead to a better understanding of the effects of genetic modifications on wood cell walls.