Relevance of the proximal domain in the amino-terminus of HERG channels for regulation by a phospholipase C-coupled hormone receptor.

Abstract

We used Xenopus oocytes co-expressing thyrotropin-releasing hormone (TRH) receptors and human ether-a-go-go-related gene (HERG) K+ channel variants carrying different amino-terminal modifications to check the relevance of the proximal domain for hormonal regulation of the channel. Deletion of the whole proximal domain (Delta 138-373) eliminates TRH-induced modifications in activation and deactivation parameters. TRH effects on activation are also suppressed with channels lacking the second half of the proximal domain or only residues 326-373. However, normal responses to TRH are obtained with Delta 346-373 channels. Thus, whereas residues 326-345 are required for the hormonal modulation of HERG activation, different proximal domain sequences contribute to set HERG gating characteristics and its regulation by TRH.

Cite this paper

@article{GmezVarela2003RelevanceOT, title={Relevance of the proximal domain in the amino-terminus of HERG channels for regulation by a phospholipase C-coupled hormone receptor.}, author={David G{\'o}mez-Varela and Francisco Barros and Cristina Guti{\'e}rrez Viloria and Teresa Giraldez and Diego G. Manso and Silvia G Dupuy and Pablo Fontes De Miranda and Pilar de la Pe{\~n}a}, journal={FEBS letters}, year={2003}, volume={535 1-3}, pages={125-30} }