title: Genetic evidence that cellulose synthase activity influences microtubule cortical array organization.
abstract: To identify factors that influence cytoskeletal organization we screened for Arabidopsis (Arabidopsis thaliana) mutants that show hypersensitivity to the microtubule destabilizing drug oryzalin. We cloned the genes corresponding to two of the 131 mutant lines obtained. The genes encoded mutant alleles of PROCUSTE1 and KORRIGAN, which both encode proteins that have previously been implicated in cellulose synthesis. Analysis of microtubules in the mutants revealed that both mutants have altered orientation of root cortical microtubules. Similarly, isoxaben, an inhibitor of cellulose synthesis, also altered the orientation of cortical microtubules while exogenous cellulose degradation did not. Thus, our results substantiate that proteins involved in cell wall biosynthesis influence cytoskeletal organization and indicate that this influence on cortical microtubule stability and orientation is correlated with cellulose synthesis rather than the integrity of the cell wall.
authors.affiliation: Department of Plant Biology, Carnegie Institution, Stanford, California 94305, USA.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Paredez
authors.forename: Staffan
authors.initials: S
authors.lastname: Persson
authors.forename: David W
authors.initials: DW
authors.lastname: Ehrhardt
authors.forename: Chris R
authors.initials: CR
authors.lastname: Somerville
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D001549:Benzamides / Q000494:pharmacology; D002480:Cellulase / Q000235:genetics / Q000502:physiology*; D002482:Cellulose / Q000096:biosynthesis*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004136:Dinitrobenzenes / Q000494:pharmacology; D005964:Glucosyltransferases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000032:analysis; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D008870:Microtubules / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure*; D009154:Mutation; D010641:Phenotype; D011993:Recombinant Fusion Proteins / Q000032:analysis; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D013424:Sulfanilamides / Q000494:pharmacology; D050257:Tubulin Modulators / Q000494:pharmacology
chemical_list: D029681:Arabidopsis Proteins; D001549:Benzamides; D004136:Dinitrobenzenes; C429844:KOR1 protein, Arabidopsis; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D013424:Sulfanilamides; D050257:Tubulin Modulators; D049452:Green Fluorescent Proteins; C012465:oryzalin; C057467:isoxaben; D002482:Cellulose; D005964:Glucosyltransferases; C457769:PRC1 protein, Arabidopsis; D002480:Cellulase