Starvation induced MTP expression in part through HNF4α

Hepatocyte nuclear factor 4α (HNF4α) is an important transcription factor governing the expression of genes involved in multiple metabolic pathways. Microsomal triglyceride transfer protein (MTP) is a rate-limiting enzyme played a role in the assembly and secretion of very low density lipoproteins (VLDLs). Fasting induces MTP expression in C57BL/6J mice. In HepG2 cells, we further demonstrate that starvation induces MTP expression, meanwhile enhances HNF4α mRNA level. It was found that MTP is an HNF4α target gene. Moreover, adenovirus mediated HNF4α overexpression and HNF4α agonists induce MTP expression in HepG2 cells. HNF4α specific siRNA represses HNF4α and MTP expression. These results suggest that starvation induces MTP expression in part through HNF4α.