Identification of an Arabidopsis Feruloyl-Coenzyme A Transferase Required for Suberin Synthesis

• DOI: 10.1104/pp.109.144907
• Publication Date: 2009-09-17T02:15:35Z
• Authors: Isabel Molina; Yonghua Li-Beisson; Fred Beisson; John B. Ohlrogge; Mike Pollard
• Keywords: Suberin; Acyltransferases; Cutin; Heterologous expression

Abstract All plants produce suberin, a lipophilic barrier of the cell wall that controls water and solute fluxes restricts pathogen infection. It is often described as heteropolymer comprised polyaliphatic polyaromatic domains. Major monomers include ω-hydroxy α,ω-dicarboxylic fatty acids, glycerol, ferulate. No genes have yet been identified for aromatic suberin pathway. Here we demonstrate Arabidopsis (Arabidopsis thaliana) gene AT5G41040, member BAHD family acyltransferases, essential incorporation ferulate into suberin. In transformed with AT5G41040 promoter:YFP fusion, reporter expression localized to layers undergoing suberization. Knockout mutants show almost complete elimination suberin-associated ester-linked However, classic lamellar structure in root periderm at5g41040 not disrupted. The reduction at5g41040-knockout seeds associated an approximate stoichiometric decrease aliphatic containing ω-hydroxyl groups. Recombinant AT5G41040p catalyzed acyl transfer from feruloyl-coenzyme A ω-hydroxyfatty acids alcohols, demonstrating encodes feruloyl transferase. CYP86B1, cytochrome P450 monooxygenase whose transcript levels correlate expression, was also investigated. Knockouts overexpression confirmed CYP86B1 oxidase required biosynthesis very-long-chain saturated α,ω-bifunctional seed composition cyp86b1 knockout surprisingly dominated by unsubstituted are incapable polymeric linkages. Together, these results challenge our current view questioning both function component existence extended polyester.