Specific association of the gene product of PKD2 with the TRPC1 channel
Specific association of the gene product of PKD2 with the TRPC1 channel
复制标题
DOI：
10.1073/pnas.96.7.3934
复制
发表时间：
1999-03-30
影响因子：
11.1
通讯作者：
Sukhatme, VP
中科院分区：
文献类型：
--
作者：
Tsiokas, L;Arnould, T;Sukhatme, VP
导致大多数常染色体显性多囊肾病病例的基因（PKD 1和PKD 2）的功能尚不清楚。PKD 1编码一个大的膜蛋白，包含几个结构基序，这些结构基序存在于参与细胞-细胞或细胞-基质相互作用的已知蛋白质中，PKD 2与PKD 1和电压激活的Ca 2+通道的主要亚基具有同源性。我们现在描述PKD 2和哺乳动物瞬时受体电位通道（TRPC）蛋白质的各种成员之间的序列同源性，被认为是由G蛋白偶联受体激活和/或耗尽内部Ca 2+商店激活。我们发现，PKD 2可以直接与TRPC 1，但不TRPC 3在转染细胞和体外。这种结合是由PKD 2的两个不同的结构域介导的，一个结构域涉及PKD 2的C-末端胞质尾区中的73个氨基酸的最小区域，该区域先前显示为构成与PKD 1的相互作用结构域，然而，该区域内的不同残基介导与TRPC 1或PKD 1的特异性相互作用。C-末端结构域对于PKD 2-TRPC 1缔合是足够的，但不是必需的。位于跨膜区段S2和S5内的更N-末端结构域（包括S5和S6之间的推定孔螺旋区域）也负责该缔合。考虑到TRPC形成功能性同源和异源多聚体复合物的能力，这些数据提供了PKD 2可能与TRPC蛋白功能相关的证据，并表明PKD 2在响应G蛋白偶联受体激活和/或储存耗尽而调节Ca 2+进入中可能起作用。
The function(s) of the genes (PKD1 and PKD2) responsible for the majority of cases of autosomal dominant polycystic kidney disease is unknown. While PKD1 encodes a large integral membrane protein containing several structural motifs found in known proteins involved in cell-cell or cell-matrix interactions, PKD2 has homology to PKD1 and the major subunit of the voltage-activated Ca2+ channels. We now describe sequence homology between PKD2 and various members of the mammalian transient receptor potential channel (TRPC) proteins, thought to be activated by G protein-coupled receptor activation and/or depletion of internal Ca2+ stores. We show that PKD2 can directly associate with TRPC1 but not TRPC3 in transfected cells and in vitro. This association is mediated by two distinct domains in PKD2, One domain involves a minimal region of 73 amino acids in the C-terminal cytoplasmic tail of PKD2 shown previously to constitute an interacting domain with PKD1, However, distinct residues within this region mediate specific interactions with TRPC1 or PKD1. The C-terminal domain is sufficient but not necessary for the PKD2-TRPC1 association. A more N-terminal domain located within transmembrane segments S2 and S5, including a putative pore helical region between S5 and S6, is also responsible for the association. Given the ability of the TRPC to form functional homo- and heteromultimeric complexes, these data provide evidence that PKD2 may be functionally related to TRPC proteins and suggest a possible role of PKD2 in modulating Ca2+ entry in response to G protein-coupled receptor activation and/or store depletion.