Evolution of RNA-Binding Proteins in Animals: Insights from Genome-Wide Analysis in the Sponge Amphimedon queenslandica

• Published in: Molecular biology and evolution 2011-08, Vol.28 (8), p.2289-2303
• Main Authors: Kerner, Pierre, Degnan, Sandie M., Marchand, Lauriane, Degnan, Bernard M., Vervoort, Michel
• Format: Article
• Language: English
• Subjects: Amino Acid Motifs; Amphimedon; Animals; Bilateria; Binding sites; Binding Sites - physiology; Biochemistry, Molecular Biology; Coral reefs; Drosophila; Evolution, Molecular; Evolutionary biology; Gene expression; Genomes; Genomics; Humans; Life Sciences; Marine; Metazoa; Molecular biology; Phylogeny; Porifera - classification; Porifera - genetics; Proteomics; Ribonucleic acid; RNA; RNA-Binding Proteins - chemistry; RNA-Binding Proteins - genetics
• ISSN: 0737-4038; 1537-1719
• DOI: 10.1093/molbev/msr046

RNA-binding proteins (RBPs) are key players in various biological processes, most notably regulation of gene expression at the posttranscriptional level. Although many RBPs have been carefully studied in model organisms, very few studies have addressed the evolution of these proteins at the scale of the animal kingdom. We identified a large set of putative RBPs encoded by the genome of the demosponge Amphimedon queenslandica, a species representing a basal animal lineage. We compared the Amphimedon RBPs with those encoded by the genomes of two bilaterians (human and Drosophila), representatives of two other basal metazoan lineages (a placozoan and a cnidarian), a choanoflagellate (probable sister group of animals), and two fungi. We established the evolutionary history of 32 families of RBPs and found that most of the diversity of RBPs present in contemporary metazoans, including humans, was already established in the last common ancestor (LCA) of animals. This includes RBPs known to be involved in key processes in bilaterians, such as development, stem and/or germ cells properties, and noncoding RNA pathways. From this analysis, we infer that a complex toolkit of RBPs was present in the LCA of animals and that it has been recruited to perform new functions during early animal evolution, in particular in relation to the acquisition of multicellularity.