Rigidity and flexibility of biological networks

TL;DR

This paper explores the concepts of rigidity and flexibility in biological networks, analyzing their structural properties and implications for functions like allostery, stability, and network balance across various biological systems.

Contribution

It provides a comprehensive overview of rigidity theory applied to biological networks and discusses potential generalizations of these concepts to all network types.

Findings

Rigidity analysis helps explain protein allostery and thermostability.

Balance of flexibility and rigidity is crucial in biological network functions.

Network concepts of rigidity and flexibility may be universally applicable.

Abstract

The network approach became a widely used tool to understand the behaviour of complex systems in the last decade. We start from a short description of structural rigidity theory. A detailed account on the combinatorial rigidity analysis of protein structures, as well as local flexibility measures of proteins and their applications in explaining allostery and thermostability is given. We also briefly discuss the network aspects of cytoskeletal tensegrity. Finally, we show the importance of the balance between functional flexibility and rigidity in protein-protein interaction, metabolic, gene regulatory and neuronal networks. Our summary raises the possibility that the concepts of flexibility and rigidity can be generalized to all networks.