摘要
在ATP门控离子通道P2X受体家族中,P2X7受体由于在结构和功能上与其他(P2X1-P2X6)受体的显著差别而备受关注。P2X7受体是由3个同源亚基组成的多聚体,其C端为P2X受体家族中最长的,与其他已知蛋白没有同源性。P2X7受体具有独特的双功能性,被ATP激活后形成非选择性阳离子通道,允许钾、钠、钙等阳离子跨膜流动,而对二价阳离子表现出相对较强的选择性,在低浓度二价阳离子环境及ATP的持续刺激下,激活的P2X7受体能形成大的孔通道。P2X7受体广泛分布在血液系统、免疫系统和骨组织等多种组织器官中,通过信号转导参与细胞增殖、蛋白合成和细胞凋亡等事件。近年来在中枢神经系统中的研究发现,P2X7受体参与神经突触传递等生理过程,并在神经性退变等病理过程中发挥重要的调节作用。其中,多种假说支持它与少突胶质细胞的损伤有密切关系。
P2X7 receptor is a member of the P2X family of ATP-gated ion channels.It received much concern for its remarkable difference from the P2X1-P2X6 subtypes in structure and function.P2X7 receptor is a trimer of homologous subunits,whose C-terminal is the longest among P2X family and is heterogenous from other known protein.P2X7 receptor is unique in that it can function as an ion channel or a nonselective pore.It can form a non-selective cation channel when activated by ATP,permeable to K＋,Na＋ and Ca2＋,especially to divalent cations.Low divalent cation concentration and continuous ATP stimulation result in pore formation.It is not clear that how P2X7 receptor can be transformed from small cation channel to large pores.P2X7 receptor is widely distributed in many tissues and organs like hematological system,hematological system and bone tissue,with the function as a signaling complex couple with multiple downstream components in events like cell proliferation,protein synthesis and apoptosis.Recent findings suggest that P2X7 receptor may play important roles not only in physiological transmitter communication but also in pathological neural injury.In the pathological process,P2X7 is important in oligodendrocyte and oligodendrocyte precursor cells（OPC） injuries with different hypothesis.
出处
《现代生物医学进展》
CAS
2010年第21期4156-4159,共4页
Progress in Modern Biomedicine
基金
湖南省自然科学基金(09JJ3070)
中南大学大学生创新性实验课题(YD09201)
