Oka K, Tzung K W, Sullivan M, Lindsay E, Baldini A, Chan L
Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Genomics. 1994 Mar 15;20(2):298-300. doi: 10.1006/geno.1994.1171.
A complementary DNA for the very-low-density lipoprotein receptor (VLDLR) that codes for a protein of 873 amino acids was cloned from a human heart cDNA library. The mature protein of 846 amino acids, preceded by a 27-residue signal peptide, shares 97% amino acid sequence identity with the rabbit VLDLR. Like the low-density lipoprotein receptor, the VLDLR contains five different domains, all of which are highly conserved between human and rabbit. A tetrapeptide NPVY that potentially serves as a signal for clustering of the VLDLR on coated pits is present in the cytoplasmic domain, which is 100% conserved between human and rabbit. We localized the VLDLR gene to chromosome 9p24 by fluorescence in situ hybridization using the cloned cDNA as hybridization probe. The high amino acid sequence homology of the VLDLR between two mammalian species suggests that the receptor plays a fundamental role in lipoprotein metabolism and that energy metabolism mediated by triglyceride utilization may be an evolutionarily highly conserved mechanism.
从人心脏cDNA文库中克隆出编码873个氨基酸蛋白质的极低密度脂蛋白受体(VLDLR)的互补DNA。由27个氨基酸残基的信号肽引导的846个氨基酸的成熟蛋白与兔VLDLR的氨基酸序列一致性为97%。与低密度脂蛋白受体一样,VLDLR包含五个不同结构域,在人和兔之间所有这些结构域都高度保守。在胞质结构域中存在一个四肽NPVY,它可能作为VLDLR在被膜小窝上聚集的信号,在人和兔之间该结构域100%保守。我们使用克隆的cDNA作为杂交探针,通过荧光原位杂交将VLDLR基因定位到9号染色体p24区域。两种哺乳动物物种之间VLDLR的高氨基酸序列同源性表明,该受体在脂蛋白代谢中起基本作用,并且由甘油三酯利用介导的能量代谢可能是一种进化上高度保守的机制。