title: Arabidopsis Deficient in Cutin Ferulate encodes a transferase required for feruloylation of ω-hydroxy fatty acids in cutin polyester.
abstract: The cuticle is a complex aliphatic polymeric layer connected to the cell wall and covers surfaces of all aerial plant organs. The cuticle prevents nonstomatal water loss, regulates gas exchange, and acts as a barrier against pathogen infection. The cuticle is synthesized by epidermal cells and predominantly consists of an aliphatic polymer matrix (cutin) and intracuticular and epicuticular waxes. Cutin monomers are primarily C(16) and C(18) unsubstituted, ω-hydroxy, and α,ω-dicarboxylic fatty acids. Phenolics such as ferulate and p-coumarate esters also contribute to a minor extent to the cutin polymer. Here, we present the characterization of a novel acyl-coenzyme A (CoA)-dependent acyl-transferase that is encoded by a gene designated Deficient in Cutin Ferulate (DCF). The DCF protein is responsible for the feruloylation of ω-hydroxy fatty acids incorporated into the cutin polymer of aerial Arabidopsis (Arabidopsis thaliana) organs. The enzyme specifically transfers hydroxycinnamic acids using ω-hydroxy fatty acids as acyl acceptors and hydroxycinnamoyl-CoAs, preferentially feruloyl-CoA and sinapoyl-CoA, as acyl donors in vitro. Arabidopsis mutant lines carrying DCF loss-of-function alleles are devoid of rosette leaf cutin ferulate and exhibit a 50% reduction in ferulic acid content in stem insoluble residues. DCF is specifically expressed in the epidermis throughout all green Arabidopsis organs. The DCF protein localizes to the cytosol, suggesting that the feruloylation of cutin monomers takes place in the cytoplasm.
authors.affiliation: Feedstocks Division, Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, California 94608, USA.
authors.forename: Carsten
authors.initials: C
authors.lastname: Rautengarten
authors.forename: Berit
authors.initials: B
authors.lastname: Ebert
authors.forename: Mario
authors.initials: M
authors.lastname: Ouellet
authors.forename: Majse
authors.initials: M
authors.lastname: Nafisi
authors.forename: Edward E K
authors.initials: EE
authors.lastname: Baidoo
authors.forename: Peter
authors.initials: P
authors.lastname: Benke
authors.forename: Maria
authors.initials: M
authors.lastname: Stranne
authors.forename: Aindrila
authors.initials: A
authors.lastname: Mukhopadhyay
authors.forename: Jay D
authors.initials: JD
authors.lastname: Keasling
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Sakuragi
authors.forename: Henrik Vibe
authors.initials: HV
authors.lastname: Scheller
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003373:Coumaric Acids / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D013058:Mass Spectrometry; D008563:Membrane Lipids / Q000378:metabolism*; D011091:Polyesters / Q000378:metabolism*; D014166:Transferases / Q000235:genetics* / Q000378:metabolism
chemical_list: D003373:Coumaric Acids; D005227:Fatty Acids; D008563:Membrane Lipids; D011091:Polyesters; C000521:cutin; C004999:ferulic acid; D014166:Transferases