TY - JOUR TI - Dynamics of genomic innovation in the unicellular ancestry of animals AU - Grau-Bové, Xavier AU - Torruella, Guifré AU - Donachie, Stuart AU - Suga, Hiroshi AU - Leonard, Guy AU - Richards, Thomas A AU - Ruiz-Trillo, Iñaki A2 - Tautz, Diethard VL - 6 PY - 2017 DA - 2017/07/20 SP - e26036 C1 - eLife 2017;6:e26036 DO - 10.7554/eLife.26036 UR - https://doi.org/10.7554/eLife.26036 AB - Which genomic innovations underpinned the origin of multicellular animals is still an open debate. Here, we investigate this question by reconstructing the genome architecture and gene family diversity of ancestral premetazoans, aiming to date the emergence of animal-like traits. Our comparative analysis involves genomes from animals and their closest unicellular relatives (the Holozoa), including four new genomes: three Ichthyosporea and Corallochytrium limacisporum. Here, we show that the earliest animals were shaped by dynamic changes in genome architecture before the emergence of multicellularity: an early burst of gene diversity in the ancestor of Holozoa, enriched in transcription factors and cell adhesion machinery, was followed by multiple and differently-timed episodes of synteny disruption, intron gain and genome expansions. Thus, the foundations of animal genome architecture were laid before the origin of complex multicellularity – highlighting the necessity of a unicellular perspective to understand early animal evolution. KW - holozoans KW - ichthyosporeans KW - comparative genomics KW - animal origins KW - gene family evolution KW - introns JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -