Generalized, Switch-Like Competitive Heterodimerization Networks

• DOI: 10.1007/s11538-006-9114-8
• Publication Date: 2007-01-10T18:08:21Z
• Authors: Olivier Cinquin; Karen M. Page
• Keywords: EXPRESSION; 0301 basic medicine; COMPLEX; signaling networks; Cell Differentiation; AUTOREGULATION; bHLH dimerization; GENE; Models, Biological; cellular differentiation; TRANSCRIPTION FACTORS; DROSOPHILA; 03 medical and health sciences; DIFFERENTIATION; Basic Helix-Loop-Helix Transcription Factors; network motifs; LOOP-HELIX PROTEINS; competitive heterodimerization; inhibitors of differentiation (Id); PHOSPHORYLATION; MYOD; Signal Transduction

High-dimensional switches have been proposed as a way to model cellular differentiation, particularly in the context of basic Helix-Loop-Helix (bHLH) competitive heterodimerization networks. A previous study derived a simple rule showing how many elements can be co-expressed, depending on the rate of competition within the network. A limitation to that rule, however, is that many biochemical parameters were considered to be identical. Here, we derive a generalized rule. This in turns allows one to study more ways in which these networks could be regulated, linking intrinsic cellular differentiation determinants to extracellular cues.