The VLDL receptor: wayward brother of the LDL receptor

The VLDL receptor binds lipoproteins that contain apolipoprotein E and consists of five functional domains that resemble the LDL receptor. Although the LDL- and VLDL-receptor genes are located on different chromosomes, their gene structure and organization are almost the same. Despite the presence of sterol regulatory element-1-like sequences in the VLDL-receptor gene, the transcription of the gene is not down-regulated by sterols. The VLDL-receptor messenger RNA is highly expressed in tissues that actively metabolize fatty acids as their source of energy. The physiological role of the chicken cognate of the VLDL receptor has been revealed recently, but its function in mammals is still debatable.