Kruppel‐like transcription factor KLF8 regulates of early adipocyte differentiation

Abstract

KLF8 is a zinc‐finger transcription factor known to play an essential role in cell cycle and differentiation. However, its physiological roles and functions in 3T3‐L1 cells remain relatively unclear. In the present study, we showed that KLF8 acts as a key regulator controlling adipocyte differentiation. In 3T3‐L1 preadipocytes, KLF8 expression was induced at an early stage of differentiation which was followed by expression of PPAR¥ã2 and C/EBP¥á. The mRNA level of KLF8 dramatically increased at 36 h and 48 h during differentiation and the protein level also gradually increased after 36 h. This induction and differentiation was attenuated significantly by the presence of small interfering RNA against KLF8, whereas overexpression of KLF8 induced 3T3‐L1 differentiation. Furthermore, overexpression of KLF8 induced PPAR¥ã2 and C/EBP¥á promoter activity and the direct binding site in C/EBP¥á promoter exists between (−205) and (−89) region. Taken together, this study provides KLF8 as a key component of the transcription factor network that controls the terminal differentiation during adipogenesis.This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2011‐0030711 and 2011‐0015665) and by Korean Research WCU grant (R31‐2008‐000‐10086‐0) from the Korean Ministry of Education, Science, and Technology.