Department of Genetics, Texas Biomedical Research Institute, San Antonio, USA.
Comp Biochem Physiol Part D Genomics Proteomics. 2011 Jun;6(2):224-34. doi: 10.1016/j.cbd.2011.04.003. Epub 2011 Apr 22.
Lipoprotein lipase (LIPL or LPL; E.C.3.1.1.34) serves a dual function as a triglyceride lipase of circulating chylomicrons and very-low-density lipoproteins (VLDL) and facilitates receptor-mediated lipoprotein uptake into heart, muscle and adipose tissue. Comparative LPL amino acid sequences and protein structures and LPL gene locations were examined using data from several vertebrate genome projects. Mammalian LPL genes usually contained 9 coding exons on the positive strand. Vertebrate LPL sequences shared 58-99% identity as compared with 33-49% sequence identities with other vascular triglyceride lipases, hepatic lipase (HL) and endothelial lipase (EL). Two human LPL N-glycosylation sites were conserved among seven predicted sites for the vertebrate LPL sequences examined. Sequence alignments, key amino acid residues and conserved predicted secondary and tertiary structures were also studied. A CpG island was identified within the 5'-untranslated region of the human LPL gene which may contribute to the higher than average (×4.5 times) level of expression reported. Phylogenetic analyses examined the relationships and potential evolutionary origins of vertebrate lipase genes, LPL, LIPG (encoding EL) and LIPC (encoding HL) which suggested that these have been derived from gene duplication events of an ancestral neutral lipase gene, prior to the appearance of fish during vertebrate evolution. Comparative divergence rates for these vertebrate sequences indicated that LPL is evolving more slowly (2-3 times) than for LIPC and LIPG genes and proteins.
脂蛋白脂肪酶（LIPL 或 LPL；E.C.3.1.1.34）具有双重功能，既是循环乳糜微粒和极低密度脂蛋白（VLDL）的甘油三酯脂肪酶，又能促进脂蛋白经受体介导进入心脏、肌肉和脂肪组织。使用来自几个脊椎动物基因组计划的数据，比较了 LPL 氨基酸序列和蛋白质结构以及 LPL 基因位置。哺乳动物 LPL 基因通常在正链上包含 9 个编码外显子。脊椎动物 LPL 序列与其他血管甘油三酯脂肪酶、肝脂肪酶（HL）和内皮脂肪酶（EL）的序列同一性为 33-49%，而与其他血管甘油三酯脂肪酶、肝脂肪酶（HL）和内皮脂肪酶（EL）的序列同一性为 58-99%。在检查的 7 个脊椎动物 LPL 序列的预测位点中，有 2 个人类 LPL N-糖基化位点保守。还研究了序列比对、关键氨基酸残基以及保守的预测二级和三级结构。在人类 LPL 基因的 5'-非翻译区中鉴定出一个 CpG 岛，这可能有助于解释报道的高于平均水平（×4.5 倍）的表达。系统发育分析检查了脊椎动物脂肪酶基因、LPL、LIPG（编码 EL）和 LIPC（编码 HL）的关系和潜在进化起源，这表明这些基因是在脊椎动物进化过程中鱼类出现之前，由一个祖先中性脂肪酶基因的基因复制事件产生的。这些脊椎动物序列的比较进化率表明，LPL 的进化速度比 LIPC 和 LIPG 基因和蛋白质慢（2-3 倍）。
