Involvement of pore helix in voltage-dependent inactivation of TRPM5 channel.

ABSTRACT: The transient receptor potential melastatin 5 (TRPM5) channel is a monovalent-permeable cation channel that is activated by intracellular Ca²⁺. Expression of TRPM5 has been shown in taste cells, pancreas, brainstem and olfactory epithelium, and this channel is thought to be involved in controlling membrane potentials. In whole-cell patch-clamp recordings, TRPM5 exhibited voltage-dependent inactivation at negative membrane potentials and time constant of voltage-dependent inactivation of TRPM5 did not depend on the intracellular Ca²⁺ concentrations between 100 and 500 nM. Alanine substitution at Y913 and I916 in the pore helix of TRPM5 increased time constant of voltage-dependent inactivation. Meanwhile, voltage-dependent inactivation was reduced in TRPM5 mutants havin

SUBMITTER: Uchida K 

PROVIDER: S-EPMC7848652 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature