The E3 ubiquitin ligase TRIM25 regulates adipocyte differentiation via proteasome-mediated degradation of PPARγ

Abstract

Metabolic disorders: TRIM-ming the fat A protein that targets peroxisome proliferator-activated receptor γ (PPARγ) (a key regulator of fat cell formation) for degradation suppresses the formation of fat. Excess fat can lead to obesity and cause type 2 diabetes and cardiovascular disease, yet little is known about the mechanisms through which fat cells arise from progenitor cells. Jang Hyun Choi and colleagues at the Ulsan National Institute of Science and Technology, Korea, have found that TRIM25, a protein implicated in cancer and antiviral immune responses, reduces the activity of PPARγ by adding a small regulatory protein that acts as a signal for degradation. Reducing the levels of TRIM25 in progenitor cells increases their ability to differentiate into fat cells. These findings suggest that TRIM25 could be a useful target for developing new therapies against obesity and metabolic disorders.