Structural determinants of Kvβ1.3‐induced channel inactivation: a hairpin modulated by PIP2

@article{Decher2008StructuralDO,
  title={Structural determinants of Kv$\beta$1.3‐induced channel inactivation: a hairpin modulated by PIP2},
  author={Niels Decher and Teresa Gonzalez and Anne Kathrin Streit and Frank B. Sachse and Vijay Renigunta and Malle Soom and Stefan H. Heinemann and J{\"u}rgen Daut and Michael C Sanguinetti},
  journal={The EMBO Journal},
  year={2008},
  volume={27}
}
Inactivation of voltage‐gated Kv1 channels can be altered by Kvβ subunits, which block the ion‐conducting pore to induce a rapid (‘N‐type’) inactivation. Here, we investigate the mechanisms and structural basis of Kvβ1.3 interaction with the pore domain of Kv1.5 channels. Inactivation induced by Kvβ1.3 was antagonized by intracellular PIP2. Mutations of R5 or T6 in Kvβ1.3 enhanced Kv1.5 inactivation and markedly reduced the effects of PIP2. R5C or T6C Kvβ1.3 also exhibited diminished binding of… Expand
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