This entry represents protein O-fucosyltransferase 2 (POFUT2), a GDP-fucose protein O-fucosyltransferase involved in one of the two pathways responsible for protein O-linked fucosylation, a post-translational modification that regulates various biological functions in cysteine-knotted proteins []. This pathway targets proteins bearing Thrombospondin type-1 (TSP1) repeats (TSRs) in the endoplasmic reticulum.POFUT2 catalyses the attachment of fucose through an O-glycosidic linkage to a conserved serine or threonine residue within the consensus sequence C1-X-X-S/T-C2 of TSRs, where C1 and C2 are the first and second cysteines of the repeat, respectively []. It O-fucosylates members of several protein families, including the ADAMTS, thrombospondin (TSP) and spondin families [].POFUT2 is required for the proper secretion of ADAMTS (a disintegrin and metalloproteinase with thrombospondin type 1 repeats) family members such as ADAMTSL1 and ADAMTS13 [, , ]. Additionally, O-fucosylation of TSRs is required for restricting epithelial to mesenchymal transition (EMT), maintaining correct patterning of mesoderm and localisation of the definitive endoderm.This entry also includes strobilurin A biosynthesis cluster protein Stl1, a component of the gene cluster mediating the biosynthesis of strobilurin A, an antifungal polyketide characterised by a beta-methoxyacrylate toxophore that targets complex III of the mitochondrial electron transport chain [].Strobilurin A biosynthesis is initiated by the construction of benzoyl CoA from phenylalanine through sequential reactions involving a phenylalanine ammonia-lyase (Str11), an oxygenase (Str8), and a retro-Claisen reaction to yield benzoic acid, which is then activated to benzoyl CoA by the CoA ligase Str10. Benzoyl CoA serves as the starter unit for the highly reducing polyketide synthase StPKS1, which produces the intermediate prestrobilutin A. The FAD-dependent oxygenase Str9 then catalyses the key oxidative rearrangement that generates the beta-methoxyacrylate toxophore, likely through epoxidation of the 2,3 olefin of prestrobilutin A followed by Meinwald rearrangement. Final methylations by Str2 and Str3 complete the synthesis of strobilurin A, while the dehydrogenases Stl2 and Str4 are involved in a shunt pathway leading to the production of bolineol [].This entry also includes some O-fucosyltransferase (5, 14, 36) from plants. These proteins are involved in glycan metabolism [].
