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How do KV4.1 channels DIFFER from KV2.1 channels?

You are investigating a genetic mutation in KIR channels which is preventing the passage of K+ across the membrane while voltage clamped at a membrane potential of -90 mV. Which of the following regions could be mutated and affecting the normal function?

In a voltage clamp experiment, when does the HERG channel inactivate, and when is a current for K+ seen with this channel?

Which of the following is FALSE regarding the K+ inward rectifying channel?

A voltage-gated sodium channel has more alpha subunits than a KV4.1 channel.

Tetraethyl ammonium (TEA) is applied to a neuron to block voltage gated potassium channels. The neuron is then voltage clamped above threshold and CURRENT is recorded. Compared to a recording at the same voltage clamp, but without TEA, which part of the current will change? HINT – think about how current and voltage plotted

You have isolated a channel during an experiment you conducted in lab. This channel allows for the passage of K+ and is NOT voltage sensitive, but only exhibits a high K+ conductance in 8.0 pH solution. Which channel might you have isolated?

If you applied scorpion beta toxin and voltage clamped a typical voltage-gated sodium channel, what might occur?

A neuron is treated with TEA to inhibit voltage-gated K+ channel and is voltage clamped at +10 mV and then at +50 mV. Which of the following would you expect to observe? Assume normal physiological conditions.

____________ channels do NOT have an inactivation domain.