Cellulose microfibrils are synthesized by membrane-embedded cellulose synthesis complexes (CSCs), currently modeled as hexamers of cellulose synthase (CESA) trimers. The three paralogous CESAs involved in secondary cell wall (SCW) cellulose biosynthesis in Arabidopsis (CESA4, CESA7, CESA8) are similar, but nonredundant, with all three isoforms required for assembly and function of the CSC. The molecular basis of protein-protein recognition among the isoforms is not well understood. To investigate the locations of the interfaces that are responsible for isoform recognition, we swapped three domains between the Arabidopsis CESAs required for SCW synthesis (CESA4, CESA7, and CESA8): N-terminus, central domain containing the catalytic core, and C-terminus. Chimeric genes with all pairwise permutations of the domains were tested for in vivo functionality within knockout mutant backgrounds of , , and . Immunoblotting with isoform-specific antibodies confirmed the anticipated protein expression in transgenic plants. The percent recovery of stem height and crystalline cellulose content was assayed, as compared to wild type, the mutant background lines, and other controls. Retention of the native central domain was sufficient for CESA8 chimeras to function, with neither its N-terminal nor C-terminal domains required. The C-terminal domain is required for class-specific function of CESA4 and CESA7, and CESA7 also requires its own N-terminus. Across all isoforms, the results indicate that the central domain, as well as the N- and C-terminal regions, contributes to class-specific function variously in Arabidopsis CESA4, CESA7, and CESA8.
National Key Laboratory of Wheat and Maize Crop Science; Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China.
In summary, we characterized a maize semi-dwarf mutant, sdw9, and successfully isolated the responsible gene, which encodes a GRAS protein, through a combination of map-based cloning and Re-sequencing (Re-seq). Our findings demonstrate that the candidate gene ZmGRAS42 regulates BR signaling genes, thereby influencing internode development. This regulatory function likely involves processes such as cell division, cell cycle regulation and cell wall synthesis.
S-acylation is the addition of a fatty acid to a cysteine residue of a protein. While this modification may profoundly alter protein behaviour, its effects on the function of plant proteins remains poorly characterized, largely as a result of the lack of basic information regarding which proteins are S-acylated and where in the proteins the modification occurs. To address this gap in our knowledge, we used an optimized acyl-resin-assisted capture assay to perform a comprehensive analysis of plant protein S-acylation from six separate tissues.
Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Genomics Research Institute (GRI), University of Pretoria, Pretoria 0002, South Africa.
() is a master regulator of fibre secondary wall deposition in (Arabidopsis), with homologs in other angiosperms and gymnosperms. However, it is poorly understood to what extent the fibre-specific regulation of the promoter, and that of its orthologs, is conserved between diverged herbaceous and woody lineages. We performed a reciprocal reporter gene analysis of orthologous promoters from Arabidopsis (), () and × () relative to secondary cell wall-specific ) and promoters, in both a non-woody (Arabidopsis) and a woody (poplar) system.
Cellulose microfibrils are synthesized by membrane-embedded cellulose synthesis complexes (CSCs), currently modeled as hexamers of cellulose synthase (CESA) trimers. The three paralogous CESAs involved in secondary cell wall (SCW) cellulose biosynthesis in Arabidopsis (CESA4, CESA7, CESA8) are similar, but nonredundant, with all three isoforms required for assembly and function of the CSC. The molecular basis of protein-protein recognition among the isoforms is not well understood.
Cellulose synthase A genes (CesAs) are responsible for cellulose biosynthesis in plant cell walls. In this study, functions of secondary wall cellulose synthases PtrCesA4, PtrCesA7-A/B and PtrCesA8-A/B were characterized during wood formation in Populus trichocarpa (Torr. & Gray).
