Structural changes in the extracellular loop 2 of the murine KCC2 potassium chloride cotransporter modulate ion transport.

ABSTRACT: K⁺-Cl^- cotransporters (KCCs) play important roles in physiological processes such as inhibitory neurotransmission and cell-volume regulation. KCCs exhibit significant variations in K⁺ affinities, yet recent atomic structures demonstrated that K⁺- and Cl^--binding sites are highly conserved, raising the question of whether additional structural elements may contribute to ion coordination. The termini and the large extracellular domain (ECD) of KCCs exhibit only low sequence identity and were already discussed as modulators of transport activity. Here, we used the extracellular loop 2 (EL2) that links transmembrane helices (TMs) 3 and 4, as a mechanism to modulate ECD folding. We compared consequences of point mutations in the K⁺

SUBMITTER: Hartmann AM 

PROVIDER: S-EPMC8191313 | biostudies-literature | 2021 Jan-Jun

REPOSITORIES: biostudies-literature