Kctd17-mediated Chop degradation promotes adipogenic differentiation

Abstract

Obesity is commonly associated with excessive adipogenesis, a process by which preadipocytes undergo differentiation into mature adipocytes; however, the mechanisms underlying adipogenesis are not completely understood. Potassium channel tetramerization domain-containing 17 (Kctd17) belongs to the Kctd superfamily and act as a substrate adaptor of the Cullin 3-RING E3 ubiquitin ligase, which is involved in a wide variety of cell functions. However, its function in the adipose tissue remains largely unknown. Here, we found that Kctd17 expression levels were increased in white adipose tissue, especially in adipocytes, in obese mice compared to lean control mice. Gain or loss of function of Kctd17 in preadipocytes inhibited or promoted adipogenesis, respectively. Furthermore, we found that Kctd17 bound to C/EBP homologous protein (Chop) to target it for ubiquitin-mediated degradation, and this process was likely associated with increased adipogenesis. In conclusion, these data suggest that Kctd17 plays an important role in adipogenesis and can be a novel therapeutic target for obesity.