8.A.221. The Very Long Chain Fatty Acid Elongase (VLCFA-E) Family
These integral membrane enzymes catalyze the first and rate-limiting reaction of the four reactions that constitute the long-chain fatty acid elongation cycle. This endoplasmic reticulum (ER)-bound enzymatic process allows the addition of 2 carbons to the chain of long- and very long-chain fatty acids (VLCFAs) per cycle (Leonard et al. 2000). The fatty acid elongase ELOVL5 is part of a protein family of multipass transmembrane proteins that reside in the endoplasmic reticulum (ER) where they catalyze long-chain fatty acid elongation. A missense variant (c.689G>T, p.Gly230Val) in ELOVL5 (of 299 aas and 7 TMSs) causes Spinocerebellar Ataxia subtype 38 (SCA38), a neurodegenerative disorder characterized by autosomal dominant inheritance, cerebellar Purkinje cell demise and adult-onset ataxia (Ferrero et al. 2023). This presumably alters the activities of several transporters in the ER and the plasma membrane.