News from IMIM, IBE, DCEXS-UPF
What makes mammals different than other groups? A group of researchers from the IMIM, IBE and DCEXS-UPF have tried to find out in a recent study where they analysed the already-sequenced genomes of 68 mammals. First author of the article, José Luis Villanueva-Cañas, designed a set of programs that enabled comparison of all the genomes, which led to a catalogue of 6,000 families of genes exclusive to mammals. These genes represent 2.5% of the genes that code for proteins in humans.
The researchers assigned each gene a possible age of origin according to the species in which they are present, and used expression data (RNA sequencing) from different tissues to see where and how the genes are expressed, as well as proteomic data to check if they are translated, i.e. if they produce proteins.
They identified the functions of some of the genes, several of which were de novo genes, which are important for acquiring new functions during evolution. Some genes were related to how the skin is structured and why it is different from that of, for example, reptiles, others produced antimicrobial peptides and others were involved in the mammary glands characteristic of mammals.
The researchers stress that the genes they found are short and usually only expressed in one, or just a few tissues. "Cataloguing mammal genes is the first step in understanding their functions", concludes Mar Albà, head of the lab where the work was done.
The work was led by José Luis Villanueva-Cañas, a member of the IMIM's Evolutionary Genomics research group, and currently a researcher at the IBE (UPF-CSIC), and ICREA researcher Mar Albà, at the IMIM and the GRIB. The study also involved David Andreu's group from the DCEXS-UPF. It has been published in the journal Genome Biology and Evolution.
Villanueva-Cañas, J.L., Ruiz-Orera, J., Agea, M.I., Gallo, M., Andreu, D. & Albà, M.M. (2017). New Genes and Functional Innovation in Mammals. Genome Biology and Evolution, 9, 1886–1900.