1.14.18.7 physiological function expression of Arabidopsis thaliana FAH1 gene, which does not contain the cytochrome b5 domain, in the Saccharomyces cerevisiae DELTAfah1 strain produces an approximately 25fold increase in alpha-hydroxyfatty acid 26:0 and reduces the levels of its 26-carbon precursor 734124 1.14.18.7 physiological function Arabidopsis thaliana Bax inhibitor-1 -mediated suppression of cell death in yeast requires Saccharomyces cerevisiae fatty acid hydroxylase 1, which has a Cb5-like domain at the N terminus and interacts with Bax inhibitor-1 734909 1.14.18.7 physiological function interaction with Arabidopsis cytochrome b5 is needed for sufficient activity. Isoform FAH1 mainly 2-hydroxylates very-long-chain fatty acids. In FAH1 knock-down lines, levels of hydroxylated fatty acids 22:0, 24:0, and 26:0 are considerably lower than in wild type, whereas the level of hydroxylated fatty acid 16:0 is marginally decreased. 2-Hydroxyfatty acids are related to resistance to oxidative stress, and isoform FAH1 or 2-hydroxy very-long-chain fatty acids show particularly strong responses to oxidative stress. Isoform FAH1 interacts with Bax inhibitor-1 via cytochrome b5 and is a key factor in Bax inhibitor-1-mediated cell death suppression 734960 1.14.18.7 physiological function interaction with Arabidopsis cytochrome b5 is needed for sufficient activity. Isoform FAH2 selectively 2-hydroxylates palmitic acid in Arabidopsis. In FAH2 knock-down lines, the level of hydroxylated fatty acid 16:0 is reduced by 22.9%, whereas the levels of other 2-hydroxyfatty acids are similar to those in wild type 734960