Role of HXXXD-motif acyltransferases in suberin biosynthesis
Abstract
Suberin is a complex polymer comprising an aliphatic polyester and an aromatic polymer, co-deposited with soluble waxes. The aliphatic polyester is composed of fatty acids, ω-hydroxy fatty acids, α,ω-dicarboxylic acids, fatty alcohols, glycerol, and ferulate. In potato, alkyl ferulates, are a major component of suberin-associated waxes. The lignin-like aromatic polymer is comprised of hydroxycinnamic acids and monolignols. Members of the HXXXD/BAHD acyltransferase family are required for the biosynthesis of the aliphatic suberin polyester and suberin-associated waxes, but their possible role in the biosynthesis of the phenolic domain of suberin remains unexplored. Here I studied the function of three BAHD candidate genes (StFHT and StFACT and St430) in the formation of the poly(phenolic) domain of suberin by characterization of wound-induced suberization in tubers from RNAi-knockdown lines. Overall, my results indicated that these genes may not function in the biosynthesis of the phenolic domain of suberin.