Figure 10: Hybrid split channels yield voltage-dependent currents.
(a) Voltage-dependent activation of the KV10.1 N-terminal/KV11.1 C-terminal assembled demi-channels. Current traces as result of 500 ms depolarizations to potentials ranging between −80 and +80 mV in 20 mV intervals in both 2 and 50 mM extracellular K+ are shown at the top. The normalized I/V relationships at both potassium concentrations are shown at the bottom. (b) Voltage-dependent activation of the KV10.2 N-terminal/KV10.1 C-terminal assembled demi-channels. Representative current records in 2 mM extracellular K+ are shown. Note the much higher current level obtained with this mixture as compared with a. Normalized I/V relationships of the mixed demi-channels (n=18) as compared with KV10.1 demi-channels (n=23) and KV10.2 continuous channels (n=17) are shown at the bottom. Error bars represent s.e. (c). Acceleration of current activation (‘Cole–Moore’ shift) by holding the KV10.1 N-terminal/KV11.1 C-terminal mixed demi-channels at more depolarized potentials. The traces correspond to representative currents obtained from oocytes held at the indicated holding potentials upon stimulation to +40 mV using the protocol represented at the top.
