Abstract
Sphingolipids are a large class of lipids ubiquitously present in eukaryotic cell membranes and essential for various cellular reactions such as signal transduction, protein transport and programmed cell death. The structural diversity of sphingolipids derives from more than 300 distinct head groups as well as various modifications on hydrocarbon chains of the hydrophobic ceramide moiety. One of the main modifications of ceramide structure is 2-hydroxylation of the fatty acids. The 2-hydroxylation of the fatty acids is catalyzed by fatty acid hydroxylase (FAH). Two Arabidopsis FAHs (AtFAH1 and AtFAH2) are localized in endoplasmic reticulum (ER) membrane. In addition, AtFAHs were activated by ER-localized cytochrome b5 through their direct interaction. Here we show the functions of AtFAHs and the roles of 2-hydroxy fatty acids in Arabidopsis.
