Energetic costs for information processing with ion channels

Communication between multiple ion channels is often necessary for a biological system to process and integrate information. Previous work has shown that sending information, electrically, from one ion channel to another has an associated energetic cost, in k_BT/bit. Here we extend this framework towards estimating energetic bounds for information processing tasks. A system where the molecular information processing needs are precisely defined is an individual nerve fiber in the snake pit organ. A single nerve fiber must integrate information from approximately 10⁶ individually noisy temperature sensitive ion channels to reliably sense mK temperature changes. To model this system, we extend the previous results on communication between pairs of channels embedded in a planar membrane, to communication between multiple channels in a more realistic geometry. By considering ion channels that simultaneously obtain information from the environment and communicate with each other, we can calculate the energetic requirements of aggregating external signals. This is a step towards understanding design principles and energetic requirements for more complex information processing systems, ranging from ion channels to neurons and intercellular neural circuits.