A hydroxycinnamoyltransferase responsible for synthesizing suberin aromatics in Arabidopsis.
Suberin, a polyester polymer in the cell wall of terrestrial plants, controls the transport of water and nutrients and protects plant from pathogenic infections and environmental stresses. Structurally, suberin consists of aliphatic and aromatic domains; p-hydroxycinnamates, such as ferulate, p-coumarate, and/or sinapate, are the major phenolic constituents of the latter. By analyzing the "wall-bound" phenolics of mutant lines of Arabidopsis deficient in a family of acyl-CoA dependent acyltransferase (BAHD) genes, we discovered that the formation of aromatic suberin in Arabidopsis, primarily in seed and root tissues, depends on a member of the BAHD superfamily of enzymes encoded by At5g41040. This enzyme exhibits an omega-hydroxyacid hydroxycinnamoyltransferase activity with an in vitro kinetic preference for feruloyl-CoA and 16-hydroxypalmitic acid. Knocking down or knocking out the At5g41040 gene in Arabidopsis reduces specifically the quantity of ferulate in suberin, but does not affect the accumulation of p-coumarate or sinapate. The loss of the suberin phenolic differentially affects the aliphatic monomer loads and alters the permeability and sensitivity of seeds and roots to salt stress. This highlights the importance of suberin aromatics in the polymer's function.
Gou
Jin-Ying
JY
Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
Yu
Xiao-Hong
XH
Liu
Chang-Jun
CJ
D000217:Acyltransferases / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001704:Biopolymers / Q000096:biosynthesis; D002473:Cell Wall / Q000187:drug effects / Q000201:enzymology; D003373:Coumaric Acids / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects; D006841:Hydrocarbons, Aromatic / Q000378:metabolism*; D007700:Kinetics; D008055:Lipids / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional / Q000187:drug effects; D009154:Mutation / Q000235:genetics; D010539:Permeability / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology; D011994:Recombinant Proteins / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000201:enzymology; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects
D029681:Arabidopsis Proteins; D001704:Biopolymers; D003373:Coumaric Acids; D004269:DNA, Bacterial; D006841:Hydrocarbons, Aromatic; D008055:Lipids; D011994:Recombinant Proteins; C036483:T-DNA; D012965:Sodium Chloride; C065875:suberin; C004999:ferulic acid; D000217:Acyltransferases; C545205:RWP1 protein, Arabidopsis