Key Laboratory of Molecular Module-Based Breeding of High Yield and Abiotic Resistant Plants in Universities of Shandong/College of Agriculture, Ludong Universtiy, Yantai, 264025, PR China; The Institute of Ecological Garden, Ludong University, Yantai, 264025, PR China.
College of Life Sciences, Ludong Universtiy, Yantai, 264025, PR China.
Plant Physiol Biochem. 2022 Aug 1;184:137-143. doi: 10.1016/j.plaphy.2022.05.015. Epub 2022 May 18.
Abundant studies have revealed that single-walled carbon nanotubes (SWCNTs) regulate plant growth. However, whether or how SWCNTs influence plant wood formation remains largely unknown. In this report, we found that SWCNTs had positive effects on poplar growth, as reflected by significantly increased plant height, leaf size, and fresh and dry weight. Transmission electron microscopy (TEM) images showed that the SWCNTs were absorbed in the exposed poplar root cells. A relatively higher content of cellulose and lignin was observed in the SWCNTs-treated poplar stems than in those of the control plants. It also showed darker phloroglucinol staining in the stems of exposed plants than that in control plants. Further analysis showed that the activities of key enzymes related to cellulose synthesis (cellulose synthase, CesA) and lignin biosynthesis (phenylalanine ammonia-lyase, PAL; cinnamate 4-hydroxylase, C4H; 4-coumarate:CoA ligase, 4CL; cinnamyl alcohol dehydrogenase, CAD) increased significantly after SWCNTs treatment. Consistent with the change trend of enzyme activity, the relative expression levels of a few lignin- and cellulose-related genes were activated by SWCNTs. Taken together, we proposed that SWCNTs have positive effects on poplar wood formation by modifying the expression of enzymes involved in the cellulose and lignin synthesis pathways. Our data suggest the modifications of wood formation through SWCNTs application could be a useful strategy for improvement of wood bioengineering.
大量研究表明，单壁碳纳米管（SWCNTs）可调节植物生长。然而，SWCNTs 如何影响植物木质部形成在很大程度上仍然未知。在本报告中，我们发现 SWCNTs 对杨树生长有积极影响，表现在植物高度、叶片大小、鲜重和干重显著增加。透射电子显微镜（TEM）图像显示，SWCNTs 被吸收在暴露的杨树根细胞中。与对照植株相比，SWCNTs 处理的杨树茎中纤维素和木质素的含量相对较高。在暴露植物的茎中，间苯三酚染色也比对照植物更深。进一步分析表明，与纤维素合成（纤维素合酶，CesA）和木质素生物合成（苯丙氨酸解氨酶，PAL；肉桂酸 4-羟化酶，C4H；4-香豆酸：CoA 连接酶，4CL；肉桂醇脱氢酶，CAD）相关的关键酶的活性在 SWCNTs 处理后显著增加。与酶活性的变化趋势一致，SWCNTs 激活了一些木质素和纤维素相关基因的相对表达水平。综上所述，我们提出 SWCNTs 通过修饰参与纤维素和木质素合成途径的酶的表达对杨树木质部形成有积极影响。我们的数据表明，通过 SWCNTs 应用来修饰木材形成可能是木材生物工程改良的一种有用策略。
