Recurrent evolution of vertebrate transcription factors by transposase capture

A recipe for new genes Most lineages contain evolutionarily novel genes, but their origin is not always clear. Cosby et al. investigated the origin of families of lineage-specific vertebrate genes (see the Perspective by Wacholder and Carvunis). Fusion between transposable elements (TEs) and host gene exons, once incorporated into the host genome, could generate new functional genes. Examination of KARABINER , a bat gene that arose through this process, shows how the retention of part of the TE within this gene allows the transcribed protein to bind throughout the genome and act as a transcriptional regulator. Thus, TEs interacting within their host genome provide the raw material to generate new combinations of functional domains that can be selected upon and incorporated within the hierarchical cellular network. Science , this issue p. eabc6405 ; see also p. 779