Phenotypic plasticity can facilitate adaptive evolution in gene regulatory circuits

BMC Evolutionary Biology

Andreas Wagner¹  Olivier C Martin²  Carlos Espinosa-Soto³ 

[1] INRA, UMR 0320/UMR 8120 Gntique Vgtale, Gif-sur- Yvette, France;The Swiss Institute of Bioinformatics. Quartier Sorge, Batiment Genopode, Lausanne, Switzerland;University of Zurich, Dept. of Biochemistry, Zurich, Switzerland

关键词: Phenotypic Plasticity;    Adaptive Evolution;    Evolutionary Search;    Interaction Density;    Alternative Phenotype;   

DOI  :  10.1186/1471-2148-11-5

学科分类：生物科学（综合）

来源: BioMed Central

【 摘 要 】

Many important evolutionary adaptations originate in the modification of gene regulatory circuits to produce new gene activity phenotypes. How do evolving populations sift through an astronomical number of circuits to find circuits with new adaptive phenotypes? The answer may often involve phenotypic plasticity. Phenotypic plasticity allows a genotype to produce different - alternative - phenotypes after non-genetic perturbations that include gene expression noise, environmental change, or epigenetic modification. We here analyze a well-studied model of gene regulatory circuits. A circuit's genotype encodes the regulatory interactions among circuit genes, and its phenotype corresponds to a stable gene activity pattern the circuit forms. For this model, we study how genotypes are arranged in genotype space, where the distance between two genotypes reflects the number of regulatory mutations that set those genotypes apart. Specifically, we address whether this arrangement favors adaptive evolution mediated by plasticity. We find that plasticity facilitates the origin of genotypes that produce a new phenotype in response to non-genetic perturbations. We also find that selection can then stabilize the new phenotype genetically, allowing it to become a circuit's dominant gene expression phenotype. These are generic properties of the circuits we study here. Taken together, our observations suggest that phenotypic plasticity frequently facilitates the evolution of novel beneficial gene activity patterns in gene regulatory circuits.

【 授权许可】

CC BY