6WLB

Structure of homotrimeric poplar cellulose synthase isoform 8

Summary for 6WLB

• Entry DOI: 10.2210/pdb6wlb/pdb
• EMDB information: 21820
• Related PRD ID: PRD_900016
• Descriptor: Cellulose synthase, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose (2 entities in total)
• Functional Keywords: cellulose, polysaccharide, cell wall, glycosyltransferase, membrane protein, translocation
• Biological source: Populus tremula x Populus tremuloides (Hybrid aspen)
• Total number of polymer chains: 3
• Total formula weight: 339935.23

Authors

Zimmer, J.,Pallinti, P.,Ho, R. (deposition date: 2020-04-19, release date: 2020-07-22, Last modification date: 2024-03-06)

Primary citation

Purushotham, P.,Ho, R.,Zimmer, J.
Architecture of a catalytically active homotrimeric plant cellulose synthase complex.
Science, 369:1089-1094, 2020

PubMed Abstract: Cellulose is an essential plant cell wall component and represents the most abundant biopolymer on Earth. Supramolecular plant cellulose synthase complexes organize multiple linear glucose polymers into microfibrils as load-bearing wall components. We determined the structure of a poplar cellulose synthase CesA homotrimer that suggests a molecular basis for cellulose microfibril formation. This complex, stabilized by cytosolic plant-conserved regions and helical exchange within the transmembrane segments, forms three channels occupied by nascent cellulose polymers. Secretion steers the polymers toward a common exit point, which could facilitate protofibril formation. CesA's N-terminal domains assemble into a cytosolic stalk that interacts with a microtubule-tethering protein and may thus be involved in CesA localization. Our data suggest how cellulose synthase complexes assemble and provide the molecular basis for plant cell wall engineering.

PubMed: 32646917
DOI: 10.1126/science.abb2978

Experimental method

ELECTRON MICROSCOPY (3.5 Å)