Tyrosine phosphorylation of Kir6.2 subunit negatively regulates cardiac K_ATP channel activity.

ABSTRACT: The plasma membrane ATP-sensitive potassium (K_ATP) channel in cardiac myocytes plays a critical role in protecting the heart against ischemic injury. Post-translational modifications regulate K_ATP channel activity and play a role in cardioprotection. However, the role of tyrosine phosphorylation in K_ATP channel regulation remains unclear. In this study, we investigated the cardiac K_ATP channel subtype Kir6.2/SUR2A and demonstrated that a protein tyrosine kinase inhibitor significantly increased the current amplitude through blunting the ATP sensitivity of K_ATP channels without altering the single-channel current or the channel surface expression. Mutation screening identified Y258 in the Kir6.2 subunit as the tyrosine phosphorylation s

SUBMITTER: Zhi Y 

PROVIDER: S-EPMC12159108 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature