PECR (peroxisomal trans-2-enoyl-CoA reductase) is a key enzyme in fatty acid metabolism that catalyzes the reduction of trans-2-enoyl-CoAs with chain lengths from 6:1 to 16:1, showing maximum activity with 10:1 CoA substrates 1. The enzyme participates in chain elongation of fatty acids and operates within peroxisomes as part of the unsaturated fatty acid biosynthesis pathway 1. PECR functions upstream of ELOVL2 (extension of very long chain fatty acid protein 2) in this metabolic cascade, where its regulation directly affects downstream lipid metabolism 1. The gene is subject to post-transcriptional regulation, as demonstrated by bta-miR-124a directly targeting PECR's 3'-untranslated region to downregulate its expression, subsequently affecting triglyceride and free fatty acid levels 1. PECR has been implicated in various disease contexts, including sepsis-induced lung injury and sepsis-associated acute kidney injury, where it appears as a key gene in disease development and immune regulation 23. Additionally, PECR variants have been associated with alcohol dependence in genome-wide association studies, though with less robust evidence compared to other loci 4. The enzyme shows predominant expression in specific kidney cell types, particularly proximal tubule and Loop of Henle cells 3.