Paine-Saunders S, Viviano B L, Saunders S
Department of Pediatrics, Washington University Medical School, St. Louis, Missouri 63110, USA.
Genomics. 1999 May 1;57(3):455-8. doi: 10.1006/geno.1999.5793.
Glypicans are a family of cell surface heparan sulfate proteoglycans that appear to play an important role in cellular growth control and differentiation, as is supported by the observation that mutations in GPC3 are responsible for Simpson-Golabi-Behmel syndrome (SGBS) in humans. Recently it has been shown that the GPC4 gene is tightly clustered with GPC3 on the X chromosome and that some patients with SGBS apparently have deletions affecting both genes. We report here the identification of a human cDNA encoding a novel glypican family member, glypican-6. This cDNA encodes a predicted protein of 554 amino acids and is structurally analogous to other members of the glypican gene family, but most highly related to glypican-4. A single GPC6 mRNA of 6.2 kb is detected most abundantly in the ovary, liver, and kidney, with lower levels of mRNA expression also detected in a wide range of other adult tissues. Radiation hybrid analysis mapped the GPC6 gene to human chromosome 13 very near the GPC5 gene, a member of the glypican family bearing strong similarity to GPC3.
磷脂酰肌醇蛋白聚糖是一类细胞表面硫酸乙酰肝素蛋白聚糖，似乎在细胞生长控制和分化中发挥重要作用，这一观点得到了如下观察结果的支持：GPC3突变会导致人类的辛普森-戈拉比-贝梅尔综合征（SGBS）。最近有研究表明，GPC4基因与GPC3在X染色体上紧密聚集，一些SGBS患者显然存在影响这两个基因的缺失。我们在此报告了一种编码新型磷脂酰肌醇蛋白聚糖家族成员——磷脂酰肌醇蛋白聚糖-6的人类cDNA的鉴定。该cDNA编码一个由554个氨基酸组成的预测蛋白，其结构与磷脂酰肌醇蛋白聚糖基因家族的其他成员相似，但与磷脂酰肌醇蛋白聚糖-4的关系最为密切。在卵巢、肝脏和肾脏中最丰富地检测到一种6.2 kb的单一GPC6 mRNA，在其他多种成人组织中也检测到较低水平的mRNA表达。辐射杂种分析将GPC6基因定位到人类13号染色体上，非常靠近GPC5基因，GPC5基因是磷脂酰肌醇蛋白聚糖家族的一个成员，与GPC3有很强的相似性。
