Role of aggregate size, multistability and communication in determining cell fate and patterning in M. xanthus

Abstract

1.The emergence of multicellular organisms that exhibit cell differentiation and stereotypic spatial arrangements has been recognized as one of the major transitions in evolution. Myxobacteria have emerged as a useful study model to investigate multicellular evolution and development. Here, we propose a multiscale model that considers cellular adhesion and movement, molecular regulatory networks (MRNs), and cell-to-cell communication to study the emergence of cell fate determination and spatial patterning of Myxococcus xanthus fruiting bodies. The model provides a dynamic accounting of the roles of MRN multistability, intercellular communication and conglomerate size in determining cell fate and patterning during M. xanthus development. It also suggests that for cell fate determination and patterning to occur, the cell aggregate must surpass a minimum size. The model also allows us to contrast alternative scenarios for the C-signal mechanism and provides stronger support for an indirect effect (as a diffusible molecule) than a direct one (as a membrane protein).