title: Genetic evidence for three unique components in primary cell-wall cellulose synthase complexes in Arabidopsis.
abstract: In higher plants, cellulose is synthesized at the plasma membrane by the cellulose synthase (CESA) complex. The catalytic core of the complex is believed to be composed of three types of CESA subunits. Indirect evidence suggests that the complex associated with primary wall cellulose deposition consists of CESA1, -3, and -6 in Arabidopsis thaliana. However, phenotypes associated with mutations in two of these genes, CESA1 and -6, suggest unequal contribution by the different CESAs to overall enzymatic activity of the complex. We present evidence that the primary complex requires three unique types of components, CESA1-, CESA3-, and CESA6-related, for activity. Removal of any of these components results in gametophytic lethality due to pollen defects, demonstrating that primary-wall cellulose synthesis is necessary for pollen development. We also show that the CESA6-related CESAs are partially functionally redundant.
authors: Department of Plant Biology, Carnegie Institution, Stanford, CA 94305, USA.
authors: Staffan
authors: S
authors: Persson
authors: Alexander
authors: A
authors: Paredez
authors: Andrew
authors: A
authors: Carroll
authors: Hildur
authors: H
authors: Palsdottir
authors: Monika
authors: M
authors: Doblin
authors: Patricia
authors: P
authors: Poindexter
authors: Natalie
authors: N
authors: Khitrov
authors: Manfred
authors: M
authors: Auer
authors: Chris R
authors: CR
authors: Somerville
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D002384:Catalysis; D002473:Cell Wall / Q000201:enzymology*; D002482:Cellulose / Q000737:chemistry; D018506:Gene Expression Regulation, Plant; D005821:Genetic Techniques; D005838:Genotype; D005964:Glucosyltransferases / Q000737:chemistry*; D008027:Light; D008854:Microscopy, Electron; D008957:Models, Genetic; D009154:Mutation; D010641:Phenotype; D011058:Pollen / Q000378:metabolism; D020033:Protein Isoforms
chemical_list: D020033:Protein Isoforms; D002482:Cellulose; D005964:Glucosyltransferases; C478648:cellulose synthase