Does sumoylation control K2P1/TWIK1 background K+ channels?

Cell. 2007 Aug 10;130(3):563-9. doi: 10.1016/j.cell.2007.06.012.


A novel model for the regulation of cell excitability has recently been proposed. It originates from the observation that the background K(+) channel K2P1 (TWIK1) may be silenced by sumoylation in Xenopus oocytes and that inactivation of the putative sumoylation site (mutation K274E) gives rise to robust current expression in transfected COS-7 cells. Here, we show that only the mutation K274E, and not K274R, is associated with an increase of K2P1 current density, suggesting a charge effect of K274E. Furthermore, we failed to observe any band shift by western blot analysis that would confirm an eventual sumoylation of K2P1 in COS-7 cells and oocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Humans
  • Potassium Channels, Tandem Pore Domain / biosynthesis
  • Potassium Channels, Tandem Pore Domain / genetics
  • Potassium Channels, Tandem Pore Domain / metabolism*
  • Small Ubiquitin-Related Modifier Proteins / metabolism*
  • Xenopus laevis


  • KCNK1 protein, human
  • Potassium Channels, Tandem Pore Domain
  • Small Ubiquitin-Related Modifier Proteins