These mating gains appear to emerge as by-products of compensatory evolution, involving functional modules such as signaling and polarized morphogenesis. In some evolved lines, enhanced pheromone response suggests rewiring of existing regulatory circuits.
We tested 18 compensated lines on 10 alternative carbon sources. Nearly half of the lines showed at least one collateral growth gain. In several cases, the original knockout did not grow, meaning compensation generated latent functional gains—not just repair.
In sum: evolutionary recovery from gene loss can rapidly generate metabolic pre-adaptations without direct selection in those future environments.
The mechanism points to regulatory reprogramming, especially altered catabolite repression and nutrient uptake. Repairing one metabolic defect can reshape the cell in ways that pre-adapt it to future environments.
This work was led by @balazs-papp-lab.bsky.social at HUN-REN Biological Research Centre, Szeged, in collaboration with @csabapallab.bsky.social , the Tamás Fehér lab and @osilander.
Can harmful gene loss become an evolutionary opportunity?
In our new work in @molbioevol.bsky.social , lab-evolved E. coli lines recovering from metabolic gene loss did more than return to normal: some surpassed wild type on nutrients never seen during lab evolution.
📎 doi.org/10.1093/molb...
Using laboratory-evolved budding yeast lineages, the work shows that recovery after gene loss does not merely compensate for reduced fitness. It can also generate unexpected phenotypic changes, including improved mating-related traits.
The broader implication: evolutionary novelty can arise through detours. Gene loss followed by growth recovery may not simply repair damage, but reshape the genotype–phenotype map and reveal hidden routes toward new cellular functions.
#ExperimentalEvolution #YeastGenetics #EvolutionaryBiology
Deleterious mutations are often viewed as evolutionary dead ends. Yet, if subsequent compensatory mutations restore growth, they may also open new adaptive trajectories that were previously inaccessible.
How can harmful gene loss contribute to evolutionary innovation? Zsuzsa Sarkadi presented new results on this question at the #EMBORulesOfTheGame. Talk title: Growth recovery after gene loss drives mating gains in yeast. @embo.org