Shannon Capacity of Signal Transduction for Multiple Independent Receptors

TL;DR

This paper extends the calculation of Shannon capacity from a single cAMP receptor to multiple independent receptors, showing capacity scales linearly with the number of receptors and is achieved by IID inputs.

Contribution

It provides a theoretical analysis of the capacity of multiple independent receptors in signal transduction, revealing linear scaling and optimal input distribution.

Findings

Capacity for n receptors is n times that of a single receptor.

IID input distribution achieves the capacity.

Capacity is achieved by leveraging feedback capacity results.

Abstract

Cyclic adenosine monophosphate (cAMP) is considered a model system for signal transduction, the mechanism by which cells exchange chemical messages. Our previous work calculated the Shannon capacity of a single cAMP receptor; however, a typical cell may have thousands of receptors operating in parallel. In this paper, we calculate the capacity of a cAMP signal transduction system with an arbitrary number of independent, indistinguishable receptors. By leveraging prior results on feedback capacity for a single receptor, we show (somewhat unexpectedly) that the capacity is achieved by an IID input distribution, and that the capacity for n receptors is n times the capacity for a single receptor.