瞬时受体电位通道蛋白的跨膜片段分析

Transmembrane Segment Analysis of Transient Receptor Potential Channel

目的分析瞬时受体电位（TRP）通道的膜拓扑结构。方法采用糖基化的方法,对传统TRP通道TRPC5的各疏水片段进行膜整合分析。结果 TRPC5通道中,S4～S8片段按顺序分别以Ncyt/Cexo和Nexo/Ccyt的方式插入到膜中,C末端位于细胞内。而S1～S3片段可能存在2种膜整合方式：一种是S1和S3整合到膜上,S2位于细胞外;另一种是混合模式,S1和S3分别位于细胞内,其N末端均位于细胞内。结论 TRPC5通道的S4～S8为跨膜片段,S1～S3片段需进一步实验验证。

Objective To investigate the membrane topology of transient receptor potential（TRP）channel. Methods Glycosylation method was used to investigate the membrane integrations of each hydrophobic segment of canonical TRP（TRPC5）. Results In TRPC5 channel,S4-S8 segments were integrated into membrane with Ncyt/Cexo and Nexo/Ccyt orientations sequentially,and C-terminus was intracellular. S1-S3 segments were integrated into membrane with two possible types. One was that S1 and S3 were integrated into membrane,whereas S2 was left out of the membrane on the cytosolic side;and the other was a mixed type that S1 and S3 were exposed to cytoplasm respectively. Both of them,the N-terminus was intracellular. Conclusion S4-S8 segments of TRPC5 are transmembrane segments. The integrations of S1-S3 segments into membrane need to be further investigated.