Molecular cloning of the two very low-density lipoprotein receptor (VLDLR) subtypes in geese and the effect of overfeeding on their MRNA levels

The objectives of this study were to verify the existence of two subtypes of the very low-density lipoprotein receptor (VLDLR) gene in geese, to investigate the effect of overfeeding on the plasma concentration of triglycerides (TG) and the very low density lipoprotein (VLDL), the activity of lipoprotein lipase (LPL), and the mRNA level of VLDLR in Sichuan White geese and Landes geese. The results indicate that there are two subtypes of the VLDLR gene in geese, and that they share a high similarity with those of other species. The expression of VLDLR I and VLDLR II was found in both tissues examined. After overfeeding, the expression level of VLDLR I in adipose tissue showed about a onefold increase (P < 0.05) in both breeds. Overfeeding induced a significant decrease of VLDLR I in skeletal muscle of both breeds, and a significant decrease of VLDLR II in Sichuan White geese (P < 0.05), but an obvious increase of VLDLR II in Landes geese (P < 0.05). In addition, overfeeding induced the increase of plasma VLDL, TG concentration and plasma LPL activity. It was concluded that VLDLR may participate in the metabolism of VLDL-TG by regulating the LPL-mediated TG hydrolysis in geese. Key words: Gene expression, geese, molecular cloning, overfeeding, very low-density lipoprotein receptor