FNDC4 (rec.) (untagged)

Irisin is a recently described exercise-induced hormone secreted by skeletal muscle in mice and humans. Irisin activates beige fat cells (beige cells have a gene expression pattern distinct from either white or brown fat and are preferentially sensitive to the polypeptide hormone irisin). Irisin is cleaved from the type I membrane protein FNDC5 and improves systemic metabolism by increasing energy expenditure. FNDC4 is an ortholog of FNDC5 with 50% identity and 86% similarity compared to Irisin. FNDC4 as well as FNDC5 are extremely well conserved between species. The human FNDC4 gene is highly enriched in liver, brain tissue and adipocytes. FNDC4 is a factor with direct therapeutic potential in inflammatory bowel disease and possibly other inflammatory diseases.