The modulation of the rate of inactivation of the mKv1.1 K+ channel by the beta subunit, Kv beta 1 and lack of effect of a Kv beta 1 N-terminal peptide.
The coexpression of the rat Kv beta 1 subunit with the mouse Kv1.1 (mKv1.1) K+ channel in Chinese hamster ovary cells caused an increase in the rate of inactivation of whole-cell current. Current decayed in a bi-exponential fashion with a fast voltage-dependent and a slower voltage-independent component. The inactivating current component accounted for around 40% of the total outward current. In contrast to previous studies using K+ channel alpha subunits, peptides based on the N-terminal of the Kv beta 1 subunit were unable to mimic the action of the entire subunit. The findings indicate differences between the inactivation induced by the Kv beta 1 subunit and the N-type inactivation mechanism associated with certain rapidly-inactivating cloned K+ channel alpha subunits.
Stephens
G J
GJ
Electrophysiology Laboratory, Wyeth Research-UK, Taplow, Berkshire, UK.
Cockett
M I
MI
Nawoschik
S P
SP
Schecter
L E
LE
Owen
D G
DG
D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D004594:Electrophysiology; D051662:Kv1.1 Potassium Channel; D008969:Molecular Sequence Data; D018408:Patch-Clamp Techniques; D010446:Peptide Fragments / Q000096:biosynthesis / Q000502:physiology*; D015221:Potassium Channels / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D024642:Potassium Channels, Voltage-Gated; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D014162:Transfection
D010446:Peptide Fragments; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D011994:Recombinant Proteins; D051662:Kv1.1 Potassium Channel