RT Journal Article
SR Electronic
T1 Multicellularity Makes Somatic Differentiation Evolutionarily Stable
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 010728
DO 10.1101/010728
A1 Mary E. Wahl
A1 Andrew W. Murray
YR 2015
UL http://biorxiv.org/content/early/2015/01/16/010728.abstract
AB Many multicellular organisms produce two cell lineages: germ cells, whose descendants form the next generation, and somatic cells which support, protect, and disperse the germ cells. This distinction has evolved independently in dozens of multicellular taxa but is absent in unicellular species. We propose that unicellular, soma-producing populations are intrinsically susceptible to invasion by non-differentiating mutants which ultimately eradicate the differentiating lineage. We argue that multicellularity can prevent the victory of such mutants. To test this hypothesis, we engineer strains of the budding yeast Saccharomyces cerevisiae that differ only in the presence or absence of multicellularity and somatic differentiation, permitting direct comparisons between organisms with different lifestyles. We find that non-differentiating mutants overtake unicellular populations but are outcompeted by multicellular differentiating strains, suggesting that multicellularity confers evolutionary stability to somatic differentiation.One Sentence Summary Using a synthetic biological approach, we show that multicellularity protects species that produce somatic cells from exploitation by common mutants.