  Conformational barcodes tag functional sites of proteins, and are decoded by
interacting molecules transmitting the incoming signal. Conformational barcodes
are modified by all co-occurring allosteric events induced by
post-translational modifications, pathogen, drug binding, etc. We argue that
fuzziness (plasticity) of conformational barcodes may be increased by
disordered protein structures, by integrative plasticity of
multi-phosphorylation events, by increased intracellular water content
(decreased molecular crowding) and by increased action of molecular chaperones.
This leads to increased plasticity of signaling and cellular networks.
Increased plasticity is both substantiated by and inducing an increased noise
level. Using the versatile network dynamics tool, Turbine
(www.turbine.linkgroup.hu), here we show that the 10% noise level expected in
cellular systems shifts a cancer-related signaling network of human cells from
its proliferative attractors to its largest, apoptotic attractor representing
their health-preserving response in the carcinogen containing and tumor
suppressor deficient environment modeled in our study. Thus, fuzzy
conformational barcodes may not only make the cellular system more plastic, and
therefore more adaptable, but may also stabilize the complex system allowing
better access to its largest attractor.
