Adaptive response and enlargement of dynamic range

TL;DR

This paper investigates the relationship between adaptive responses and dynamic range enlargement in cellular signaling, revealing that specific adaptive responses are not necessary for dynamic range expansion, which can be achieved through biochemical modifications.

Contribution

It demonstrates that dynamic range enlargement arises from activity-dependent modulation of protein responsiveness, independent of the type of adaptive response.

Findings

Precise adaptive response does not guarantee large dynamic range.

Dynamic range can be expanded via biochemical modifications like methylation and phosphorylation.

Adaptive response and dynamic range enlargement are related but distinct phenomena.

Abstract

Many membrane channels and receptors exhibit adaptive, or desensitized, response to a strong sustained input stimulus, often supported by protein activity-dependent inactivation. Adaptive response is thought to be related to various cellular functions such as homeostasis and enlargement of dynamic range by background compensation. Here we study the quantitative relation between adaptive response and background compensation within a modeling framework. We show that any particular type of adaptive response is neither sufficient nor necessary for adaptive enlargement of dynamic range. In particular a precise adaptive response, where system activity is maintained at a constant level at steady state, does not ensure a large dynamic range neither in input signal nor in system output. A general mechanism for input dynamic range enlargement can come about from the activity-dependent modulation of protein responsiveness by multiple biochemical modification, regardless of the type of adaptive response it induces. Therefore hierarchical biochemical processes such as methylation and phosphorylation are natural candidates to induce this property in signaling systems.