Phenotypic plasticity can facilitate adaptive evolution in gene regulatory circuits

Area of Science:

• Evolutionary biology
• Systems biology
• Genetics

Background:

• Evolutionary adaptations often arise from modifications in gene regulatory circuits, leading to new gene activity phenotypes.
• Evolving populations face the challenge of navigating vast numbers of potential circuits to find adaptive ones.
• Phenotypic plasticity, enabling genotypes to produce diverse phenotypes in response to non-genetic factors, is a key mechanism in this process.

Purpose of the Study:

• To investigate how the arrangement of genotypes in genotype space influences adaptive evolution mediated by phenotypic plasticity.
• To determine if phenotypic plasticity facilitates the discovery and genetic stabilization of novel gene activity patterns.

Main Methods:

• Analysis of a well-established model of gene regulatory circuits.
• Examination of genotype space, where distance represents regulatory mutations.
• Assessment of how genotype arrangement supports plasticity-driven evolution.

Main Results:

• Phenotypic plasticity promotes the emergence of genotypes that yield new phenotypes upon non-genetic perturbations.
• Genetic selection can subsequently stabilize these novel phenotypes, making them dominant.
• These findings apply broadly to the studied circuit models.

Conclusions:

• Phenotypic plasticity plays a frequent and significant role in the evolution of novel, beneficial gene activity patterns within gene regulatory circuits.