Xu X Z, Li H S, Guggino W B, Montell C
Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Cell. 1997 Jun 27;89(7):1155-64. doi: 10.1016/s0092-8674(00)80302-5.
The Drosophila retinal-specific protein, TRP (transient receptor potential), is the founding member of a family of store-operated channels (SOCs) conserved from C. elegans to humans. In vitro studies indicate that TRP is a SOC, but that the related retinal protein, TRPL, is constitutively active. In the current work, we report that coexpression of TRP and TRPL leads to a store-operated, outwardly rectifying current distinct from that owing to either TRP or TRPL alone. TRP and TRPL interact directly, indicating that the TRP-TRPL-dependent current is mediated by heteromultimeric association between the two subunits. We propose that the light-activated current in photoreceptor cells is produced by a combination of TRP homo- and TRP-TRPL heteromultimers.
果蝇视网膜特异性蛋白TRP（瞬时受体电位）是从秀丽隐杆线虫到人类保守的储存操纵通道（SOCs）家族的创始成员。体外研究表明，TRP是一种SOC，但相关的视网膜蛋白TRPL是组成型激活的。在当前的工作中，我们报告TRP和TRPL的共表达导致一种储存操纵的外向整流电流，该电流不同于单独由TRP或TRPL引起的电流。TRP和TRPL直接相互作用，表明TRP-TRPL依赖性电流是由两个亚基之间的异源多聚体缔合介导的。我们提出光感受器细胞中的光激活电流是由TRP同多聚体和TRP-TRPL异源多聚体共同产生的。
