title: Profiling candidate genes involved in wax biosynthesis in Arabidopsis thaliana by microarray analysis.
abstract: Plant epidermal wax forms a hydrophobic layer covering aerial plant organs which constitutes a barrier against uncontrolled water loss and biotic stresses. Wax biosynthesis requires the coordinated activity of a large number of enzymes for the formation of saturated very-long-chain fatty acids and their further transformation in several aliphatic compounds. We found in the available database 282 candidate genes that may play a role in wax synthesis, regulation and transport. To identify the most interesting candidates, we measured the level of expression of 204 genes in the aerial parts of 15-day-old Arabidopsis seedlings by performing microarray experiments. We showed that only 25% of the putative candidates were expressed to significant levels in our samples, thus significantly reducing the number of genes which will be worth studying using reverse genetics to demonstrate their involvement in wax accumulation. We identified a beta-keto acyl-CoA synthase gene, At5g43760, which is co-regulated with the wax gene CER6 in a number of conditions and organs. By contrast, we showed that neither the fatty acyl-CoA reductase genes nor the wax synthase genes were expressed in 15-day-old leaves and stems, raising questions about the identity of the enzymes involved in the acyl-reduction pathway that accounts for 20% of the total wax amount.
authors.affiliation: Laboratoire de Biogenèse Membranaire, CNRS, UMR 5200, Université Victor Segalen Bordeaux 2, 146 rue léo Saignat, Case 92, 33076 Bordeaux Cedex, France. Patricia.costaglioli@estbb.u-bordeaux2.fr
authors.forename: Patricia
authors.initials: P
authors.lastname: Costaglioli
authors.forename: Jérôme
authors.initials: J
authors.lastname: Joubès
authors.forename: Christel
authors.initials: C
authors.lastname: Garcia
authors.forename: Marianne
authors.initials: M
authors.lastname: Stef
authors.forename: Benoît
authors.initials: B
authors.lastname: Arveiler
authors.forename: René
authors.initials: R
authors.lastname: Lessire
authors.forename: Bertrand
authors.initials: B
authors.lastname: Garbay
mesh_terms: D000217:Acyltransferases / Q000096:biosynthesis / Q000235:genetics; D000445:Aldehyde Oxidoreductases / Q000096:biosynthesis / Q000235:genetics; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics; D019755:Carbon-Carbon Lyases; D020869:Gene Expression Profiling; D017343:Genes, Plant; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D036226:Seedlings / Q000378:metabolism; D013214:Starch Synthase / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D013997:Time Factors
chemical_list: D000217:Acyltransferases; D000445:Aldehyde Oxidoreductases; D029681:Arabidopsis Proteins; D019755:Carbon-Carbon Lyases; D009687:Nuclear Proteins; D010940:Plant Proteins; D013214:Starch Synthase; C101547:CER protein, Arabidopsis; C060756:waxy protein, plant; C021351:hexadecanal dehydrogenase (acylating); C120018:CUT1 protein, Arabidopsis; C103487:At5g57800 protein, Arabidopsis