Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
Am J Hum Genet. 2011 Aug 12;89(2):313-9. doi: 10.1016/j.ajhg.2011.07.010.
Insulin-like growth factor binding proteins (IGFBPs) play important physiological functions through the modulation of IGF signaling as well as IGF-independent mechanisms. Despite the established role of IGFs in development, a similar role for the seven known IGFBPs has not been established in humans. Here, we show that an autosomal-recessive syndrome that consists of progressive retinal arterial macroaneurysms and supravalvular pulmonic stenosis is caused by mutation of IGFBP7. Consistent with the recently established inhibitory role of IGFBP7 on BRAF signaling, the BRAF/MEK/ERK pathway is upregulated in these patients, which may explain why the cardiac phenotype overlaps with other disorders characterized by germline mutations in this pathway. The retinal phenotype appears to be mediated by a role in vascular endothelium, where IGFBP7 is highly expressed.
胰岛素样生长因子结合蛋白 (IGFBPs) 通过调节 IGF 信号以及 IGF 独立机制发挥重要的生理功能。尽管 IGF 在发育过程中具有重要作用,但在人类中,七种已知的 IGFBPs 是否具有类似作用尚未确定。在这里,我们发现一种由进行性视网膜动脉大动脉瘤和瓣上肺动脉狭窄组成的常染色体隐性综合征是由 IGFBP7 突变引起的。与最近确立的 IGFBP7 对 BRAF 信号的抑制作用一致,这些患者中的 BRAF/MEK/ERK 通路被上调,这可能解释了为什么心脏表型与其他由该通路中的种系突变引起的疾病重叠。视网膜表型似乎通过在血管内皮细胞中发挥作用来介导,IGFBP7 在血管内皮细胞中高度表达。