[关键词]
[摘要]
先天性白内障(CC)是婴幼儿视力障碍的重要原因之一,约30%的病例与单基因突变有关,是儿童防盲治盲的核心病种之一。晶状体透明性的维持与膜蛋白介导的细胞间通讯、水分转运及纤维细胞规则排列密切相关。文章围绕与晶状体膜功能相关的缝隙连接蛋白基因(GJA8、GJA3),主要固有膜蛋白基因(MIP/AQP0)及晶状体膜固有蛋白2基因(LIM2),对相关单基因突变的遗传方式、临床表型及致病机制进行综述。现有研究表明,GJA8和GJA3突变主要通过影响缝隙连接通道功能、蛋白定位及半通道开放状态,破坏晶状体细胞稳态; MIP/AQP0突变可影响水分转运和细胞间黏附,导致纤维细胞排列异常; LIM2突变除经典的常染色体隐性遗传外,显性突变亦可通过异常二硫键形成影响膜蛋白复合体组装,从而导致晶状体混浊。系统梳理上述基因的突变特点和作用机制,有助于理解膜蛋白异常参与先天性白内障发生发展的过程,并为分子诊断、遗传咨询及后续干预研究提供参考。
[Key word]
[Abstract]
Congenital cataract(CC)is one of the important causes of visual impairment in infants and young children. Approximately 30% of cases are associated with monogenic mutations. It is one of the core diseases in pediatric blindness prevention and treatment. The maintenance of lens transparency is closely related to membrane protein-mediated intercellular communication, water transport, and the orderly arrangement of fiber cells. This review focuses on the gap junction protein genes(GJA8 and GJA3), related to lens membrane function, the major intrinsic protein gene(MIP/AQP0), and the lens intrinsic membrane protein 2 gene(LIM2), and summarizes the inheritance patterns, clinical phenotypes, and pathogenic mechanisms of related monogenic mutations. Current evidence indicates that GJA8 and GJA3 mutations mainly disrupt lens cell homeostasis by affecting gap junction channel function, protein localization, and hemichannel opening; MIP/AQP0 mutations may impair water transport and intercellular adhesion, leading to abnormal fiber cell arrangement; in addition to the classic autosomal recessive inheritance pattern, dominant LIM2 mutations may affect membrane protein complex assembly through aberrant disulfide bond formation, thereby causing lens opacification. A systematic review of the mutational characteristics and mechanisms of these genes may help clarify the role of membrane protein abnormalities in the development and progression of CC and provide a reference for molecular diagnosis, genetic counseling, and subsequent intervention research.
[中图分类号]
[基金项目]
陕西省卫生健康高层次人才培育计划团队项目