Rewired

The role of whole genome duplication in vertebrate adaptation

Summary

Genome evolution – changes in genome size, structure, and function over time – is among the most fundamental process shaping earths biodiversity. Understanding the drivers of genome evolution is therefore a key goal in evolutionary biology. One of the most dramatic genome evolution events is whole genome duplication (WGD). Intriguingly, WGD have played a crucial role in evolution of vertebrates. The complete functional redundancy following WGD has been hypothesized to catalyze evolution of novel adaptations, yet this is still hotly debated. The core of this debate boils down to the relative importance of adaptive versus neutral variation. A decade of research on vertebrate genomes, including our own work on salmonids, has revealed that accelerated evolution in one duplicate copy is a hallmark of genome evolution following WGDs. But does this increased rate of seemingly novel gene functions functional reflect the rise of novel adaptations – or simply loss of purifying selection due to redundancy (i.e. neutral evolution)?

REWIRED will address this longstanding and fundamental crux in evolutionary biology by taking advantage of salmonid fish as an emerging and powerful study system. We will apply recently developed computational methods to new extensive functional genomics datasets. This will enable us to overcome existing methodological limitations and distinguish between adaptive and neutral divergence. Finally, we will use bold and innovative experimental approaches, combining state-of-the-art gene editing with detailed molecular phenotyping of in vitro tissue function. This allows us to move beyond statistical signals, linking novel adaptive gene regulation – “REWIRING” – with biological function. The project is expected to bring our knowledge of how WGDs have impacted shape vertebrate genome evolution from a descriptive- towards a mechanistic and functional understanding, and thus make significant impact to the field of genome- and evolutionary biology.