Fengcheng Li1,2,3,4, Guosheng Xie1,2,4, Jiangfeng Huang1,2,4, Ran Zhang1,2,4, Li Yu1,2,4, Miaomiao Zhang1,5,4, Yanting Wang1,2,4, Ao Li1,2,4, Xukai Li1,2,4, Tao Xia1,5,4, Chengcheng Qu6, Fan Hu7,8, Arthur J. Ragauskas7,8, Liangcai Peng1,2,4
1Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan, China
2College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
3Key Laboratory of Crop Physiology, Ecology, Genetics and Breeding, Ministry of Agriculture, Rice Research Institute, Shenyang Agricultural University, Shenyang, China
4National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
5College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
6State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
7Department of Chemical and Biomolecular Engineering, The University of Tennessee- Knoxville, Knoxville, TN, USA
8Department of Forestry, The University of Tennessee-Knoxville, Knoxville, TN, USA
Tóm tắt
SummaryGenetic modification of plant cell walls has been posed to reduce lignocellulose recalcitrance for enhancing biomass saccharification. Since cellulose synthase (CESA) gene was first identified, several dozen CESA mutants have been reported, but almost all mutants exhibit the defective phenotypes in plant growth and development. In this study, the rice (Oryza sativa) Osfc16 mutant with substitutions (W481C, P482S) at P‐CR conserved site in CESA9 shows a slightly affected plant growth and higher biomass yield by 25%–41% compared with wild type (Nipponbare, a japonica variety). Chemical and ultrastructural analyses indicate that Osfc16 has a significantly reduced cellulose crystallinity (CrI) and thinner secondary cell walls compared with wild type. CESA co‐IP detection, together with implementations of a proteasome inhibitor (MG132) and two distinct cellulose inhibitors (Calcofluor, CGA), shows that CESA9 mutation could affect integrity of CESA4/7/9 complexes, which may lead to rapid CESA proteasome degradation for low‐DP cellulose biosynthesis. These may reduce cellulose CrI, which improves plant lodging resistance, a major and integrated agronomic trait on plant growth and grain production, and enhances biomass enzymatic saccharification by up to 2.3‐fold and ethanol productivity by 34%–42%. This study has for the first time reported a direct modification for the low‐DP cellulose production that has broad applications in biomass industries.
