RT Journal Article SR Electronic T1 Enhanced plasticity of programmed DNA elimination boosts adaptive potential in suboptimal environments JF bioRxiv FD Cold Spring Harbor Laboratory SP 448316 DO 10.1101/448316 A1 Valerio Vitali A1 Rebecca Hagen A1 Francesco Catania YR 2018 UL http://biorxiv.org/content/early/2018/10/20/448316.abstract AB The impact of ecological changes on the development of new somatic genomes has thus far been neglected. This oversight yields an incomplete understanding of the mechanisms that underlie environmental adaptation and can be tackled leveraging the biological properties of ciliates. When Paramecium reproduces sexually, its polyploid somatic genome regenerates from the germline genome via a developmental process, Programmed DNA elimination (PDE), that involves the removal of thousands of ORF-interrupting germline sequences. Here, we demonstrate that exposure to sub-optimal temperatures impacts PDE efficiency, prompting the emergence of hundreds of alternative DNA splicing variants that dually embody cryptic (germline) variation and de novo induced (somatic) mutations. In contrast to trivial biological errors, many of these alternative DNA isoforms display a patterned genomic topography, are epigenetically controlled, inherited trans-somatically, and under purifying selection. Developmental thermoplasticity in Paramecium is a likely source of evolutionary innovation.