李积胜,王晓峰等《Journal of Experimental Botany》2020年
论文题目:Hydrogen sulfide promotes hypocotyl elongation via increasing cellulose content and changing the arrangement of cellulose fibrils inalfalfa
论文作者:李积胜1,†,王晓峰1,†, 王肖2,马佩云2,印伟力1,王晏清3,陈莹1,陈少林1,*,贾红磊2,*
论文摘要:Hydrogen sulfide (H2S) is known to have positive physiological functions in plant growth, but limited data are available on its influence on cell walls. Here, we demonstrate a novel mechanism by which H2S regulates the biosynthesis and deposition of cell wall cellulose in alfalfa (Medicago sativa). Treatment with NaHS was found to increase the length of epidermal cells in the hypocotyl, and transcriptome analysis indicated that it caused the differential expression of numerous of cell wall-related genes. These differentially expressed genes were directly associated with the biosynthesis of cellulose and hemicellulose, and with the degradation of pectin. Analysis of cell wall composition showed that NaHS treatment increased the contents of cellulose and hemicellulose, but decreased the pectin content. Atomic force microscopy revealed that treatment with NaHS decreased the diameter of cellulose fibrils, altered the arrangement of the fibrillar bundles, and increased the spacing between the bundles. The dynamics of cellulose synthase complexes (CSCs) were closely related to cellulose synthesis, and NaHS increased the rate of mobility of the particles. Overall, our results suggest that the H2S signal enhances the plasticity of the cell wall by regulating the deposition of cellulose fibrils and by decreasing the pectin content. The resulting increases in cellulose and hemicellulose contents lead to cell wall expansion and cell elongation.
论文链接:https://doi:10.1093/jxb/eraa318