Figure 5.

Peroxisome‐ER cooperation in PUFA synthesis at ACBD5‐mediated MCSs. PUFAs are synthesized at the ER by combined FA elongation and desaturation. However, peroxisomes cooperate with the ER in the synthesis of n‐3 long‐chain PUFAs such as docosahexaenoic acid (DHA) (22:6n‐3) as the ER appears to lack potent fatty acid Δ4‐desaturase activity. To this end, exploiting Δ6 desaturase activities, the ER produces 24:6 (n‐3) FA, which are subsequently chain‐shortened by one round of β‐oxidation in peroxisomes. In this scenario, ACBD5 may facilitate efficient transport of 24:6 (n‐3) CoA from the ER to peroxisomes at MCSs. PUFA, polyunsaturated fatty acid