title: How Transcription Networks Evolve and Produce Biological Novelty.
abstract: The rewiring of gene regulatory networks over evolutionary timescales produces changes in the patterns of gene expression and is a major source of diversity among species. Yet the molecular mechanisms underlying evolutionary rewiring are only beginning to be understood. Here, we discuss recent analyses in ascomycete yeasts that have revealed several general principles of network rewiring. Specifically, we discuss how transcription networks can maintain a functional output despite changes in mechanism, how specific types of constraints alter available evolutionary trajectories, and how regulatory rewiring can ultimately lead to phenotypic novelty. We also argue that the structure and "logic" of extant gene regulatory networks can largely be accounted for by constraints that shape their evolutionary trajectories.
authors.affiliation: Departments of Microbiology and Immunology and of Biochemistry and Biophysics, University of California, San Francisco, California 94158.
authors.forename: Isabel
authors.initials: I
authors.lastname: Nocedal
authors.affiliation: Departments of Microbiology and Immunology and of Biochemistry and Biophysics, University of California, San Francisco, California 94158.
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Johnson
mesh_terms: D001203:Ascomycota / Q000235:genetics*; D005075:Biological Evolution; D019143:Evolution, Molecular; D053263:Gene Regulatory Networks / Q000235:genetics*; D010641:Phenotype