MiRP2 forms potassium channels in skeletal muscle with Kv3.4 and is associated with periodic paralysis.
Article Details
- CitationCopy to clipboard
Abbott GW, Butler MH, Bendahhou S, Dalakas MC, Ptacek LJ, Goldstein SA
MiRP2 forms potassium channels in skeletal muscle with Kv3.4 and is associated with periodic paralysis.
Cell. 2001 Jan 26;104(2):217-31. doi: 10.1016/s0092-8674(01)00207-0.
- PubMed ID
- 11207363 [ View in PubMed]
- Abstract
The subthreshold, voltage-gated potassium channel of skeletal muscle is shown to contain MinK-related peptide 2 (MiRP2) and the pore-forming subunit Kv3.4. MiRP2-Kv3.4 channels differ from Kv3.4 channels in unitary conductance, voltage-dependent activation, recovery from inactivation, steady-state open probability, and block by a peptide toxin. Thus, MiRP2-Kv3.4 channels set resting membrane potential (RMP) and do not produce afterhyperpolarization or cumulative inactivation to limit action potential frequency. A missense mutation is identified in the gene for MiRP2 (KCNE3) in two families with periodic paralysis and found to segregate with the disease. Mutant MiRP2-Kv3.4 complexes exhibit reduced current density and diminished capacity to set RMP. Thus, MiRP2 operates with a classical potassium channel subunit to govern skeletal muscle function and pathophysiology.