Catalyzes the third of the four reactions of the long-chainfatty acids elongation cycle. This endoplasmic reticulum-boundenzymatic process, allows the addition of two carbons to the chain oflong- and very long-chain fatty acids/VLCFAs per cycle. This enzymecatalyzes the dehydration of the 3-hydroxyacyl-CoA intermediate intotrans-2, 3-enoyl-CoA, within each cycle of fatty acid elongation. Thereby, it participates in the production of VLCFAs of different chainlengths that are involved in multiple biological processes asprecursors of membrane lipids and lipid mediators. May be involved inRac1-signaling pathways leading to the modulation of gene expression. Promotes insulin receptor/INSR autophosphorylation and is involved inINSR internalization. [1-3]

MENQVLTPHVYWAQRHRELYLRVELSDVQNPAISITENVLHFKAQGHGAKGDNVYEFHLEFLDLVKPEPVYKLTQRQVNITVQKKVSQWWERLTKQEKRPLFLAPDFDRWLDESDAEMELRAKEEERLNKLRLESEGSPETLTNLRKGYLFMYNLVQFLGFSWIFVNLTVRFCILGKESFYDTFHTVADMMYFCQMLAVVETINAAIGVTTSPVLPSLIQLLGRNFILFIIFGTMEEMQNKAVVFFVFYLWSAIEIFRYSFYMLTCIDMDWKVLTWLRYTLWIPLYPLGCLAEAVSVIQSIPIFNETGRFSFTLPYPVKIKVRFSFFLQIYLIMIFLGLYINFRHLYKQRRRRYGQKKKKIH