PT  - JOURNAL ARTICLE
AU  - Somya Mani
AU  - Tsvi Tlusty
TI  - Frequent non-genic adaptation and gene birth through the interplay of functionality and expression in a population model
AID  - 10.1101/2022.07.31.502179
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.07.31.502179
4099  - http://biorxiv.org/content/early/2022/08/02/2022.07.31.502179.short
4100  - http://biorxiv.org/content/early/2022/08/02/2022.07.31.502179.full
AB  - Over evolutionary timescales, genomic loci switch between functional and non-functional states through processes such as pseudogenization and de novo gene birth. Here we ask about the likelihood and rate of functionalization of non-functional loci. We simulate an evolutionary model to look at the contributions of mutations and structural variation using biologically reasonable distributions of mutational effects. We find that a wide range of mutational effects are conducive to functionalization, thus indicating the ubiquity of this process. During functionalization, loci transition from a mutation dominated ’learning’ phase to a selection dominated adaptation phase. Interestingly, in the special case of de novo gene birth, whereby non-functional loci begin to express a functional product, we find that expression level changes lead to rare, extreme jumps in fitness, whereas sustained adaptation is driven by product functionality. Our work supports the idea that the potential for adaptation is spread widely across the genome, and our results offer mechanistic insights into the process of de novo gene birth.Competing Interest StatementThe authors have declared no competing interest.