Certain species of frogs in the genus Phyllobates have a powerful defensive adaptation—their skin can secrete a milky fluid that contains an extremely toxic compound called batrachotoxin (BTX). These frogs, which are found in Colombia, are known as poison dart frogs because some indigenous Colombian hunters coat the tips of their blowgun darts with the frogs' skin secretions. An animal hit by one of these darts dies quickly. What is the mechanism of action of BTX? Identify a research technique that could be used to discover how BTX affects specific membrane proteins. Based on the graph in Question 11, what would you expect this technique to show?

Verified step by step guidance

1. Identify the primary action of BTX: Batrachotoxin (BTX) works by binding to voltage-gated sodium channels on nerve and muscle cells, altering the channels' configuration so that they cannot close. This results in continuous sodium ion influx, leading to uncontrolled nerve firing and muscle contractions, eventually causing paralysis and death.
2. Choose a research technique: To study how BTX affects specific membrane proteins, electrophysiology, specifically the patch-clamp technique, can be used. This method allows researchers to measure the ionic currents passing through individual ion channels in real-time.
3. Prepare the experimental setup: In the patch-clamp technique, a glass pipette with a very fine tip is used to isolate a small patch of membrane containing ion channels. The pipette tip is sealed onto the cell membrane, and the electrical activity of the ion channels within that patch can be recorded.
4. Conduct the experiment: Apply BTX to the cells under study and use the patch-clamp setup to record changes in the sodium channel activity. Observe the behavior of the channels in the presence of BTX, noting any changes in the frequency, duration, and amplitude of channel openings.
5. Analyze and interpret the results: Based on the known mechanism of BTX, you would expect the patch-clamp recordings to show an increase in sodium channel activity, with channels remaining open longer than usual. This would confirm BTX's role in disrupting normal cellular function by modifying ion channel behavior.