title: Phylogenetically distinct cellulose synthase genes support secondary wall thickening in arabidopsis shoot trichomes and cotton fiber.
abstract: Abstract Through exploring potential analogies between cotton seed trichomes (or cotton fiber) and arabidopsis shoot trichomes we discovered that CesAs from either the primary or secondary wall phylogenetic clades can support secondary wall thickening. CesA genes that typically support primary wall synthesis, AtCesA1,2,3,5, and 6, underpin expansion and secondary wall thickening of arabidopsis shoot trichomes. In contrast, apparent orthologs of CesA genes that support secondary wall synthesis in arabidopsis xylem, AtCesA4,7, and 8, are up-regulated for cotton fiber secondary wall deposition. These conclusions arose from: (a) analyzing the expression of CesA genes in arabidopsis shoot trichomes; (b) observing birefringent secondary walls in arabidopsis shoot trichomes with mutations in AtCesA4, 7, or 8; (c) assaying up-regulated genes during different stages of cotton fiber development; and (d) comparing genes that were co-expressed with primary or secondary wall CesAs in arabidopsis with genes up-regulated in arabidopsis trichomes, arabidopsis secondary xylem, or cotton fiber during primary or secondary wall deposition. Cumulatively, the data show that: (a) the xylem of arabidopsis provides the best model for secondary wall cellulose synthesis in cotton fiber; and (b) CesA genes within a "cell wall toolbox" are used in diverse ways for the construction of particular specialized cell walls.
authors.affiliation: Department of Plant Biology, North Carolina State University, Raleigh, NC 27695-7612, USA.
authors.forename: Lissete
authors.initials: L
authors.lastname: Betancur
authors.forename: Bir
authors.initials: B
authors.lastname: Singh
authors.forename: Ryan A
authors.initials: RA
authors.lastname: Rapp
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Wendel
authors.forename: M David
authors.initials: MD
authors.lastname: Marks
authors.forename: Alison W
authors.initials: AW
authors.lastname: Roberts
authors.forename: Candace H
authors.initials: CH
authors.lastname: Haigler
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000502:physiology; D002473:Cell Wall / Q000378:metabolism*; D032561:Cotton Fiber; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D005964:Glucosyltransferases / Q000145:classification* / Q000235:genetics / Q000502:physiology; D003368:Gossypium / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D010940:Plant Proteins / Q000145:classification* / Q000235:genetics / Q000502:physiology; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D005964:Glucosyltransferases; C478648:cellulose synthase