Publication Date: 2016.
Macroevolutionary trends exhibited by retroviruses are complex and not entirely understood. The sloth endogenized foamy-like retrovirus (SloEFV), which demonstrates incongruence in virus-host evolution among extant sloths (Order Folivora), has not been investigated heretofore in any extinct sloth lineages and its premodern history within folivorans is therefore unknown. Determining retroviral coevolutionary trends requires a robust phylogeny of the viral host, but the highly reducedmodern sloth fauna (6 species in 2 genera) does not adequately represent whatwas once a highly diversified clade (∼100 genera) of placental mammals. At present, the amount of molecular data available for extinct sloth taxa is limited, and analytical results based on these data tend to conflict with phylogenetic inferences made on the basis of morphological studies. To augment themolecular data set, we applied hybridization capture and next-generation Illumina sequencing to two extinct and three extant sloth species to retrieve full mitochondrial genomes (mitogenomes) from the hosts and the polymerase gene of SloEFV. The results produced a fully resolved and well-supported phylogeny that supports dividing crown families into two major clades: 1) The three-toed sloth, Bradypus, and Nothrotheriidae and 2) Megalonychidae, including the two-toed sloth, Choloepus, and Mylodontidae. Our calibrated time tree indicates that the Miocene epoch (23.5 Ma), particularly its earlier part, was an important interval for folivoran diversification. Both extant and extinct sloths demonstrate multiple complex invasions of SloEFV into the ancestral sloth germline followed by subsequent introgressions across different sloth lineages. Thus, sloth mitogenome and SloEFV evolution occurred separately and in parallel among sloths.
Author affiliation: Slater, Graham J.. University of Chicago; Estados Unidos. National Museum of Natural History; Estados Unidos
Author affiliation: Cui, Pin. Leibniz Institute for Zoo and Wildlife Research; Alemania
Author affiliation: Forasiepi, Analia Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina
Author affiliation: Lenz, Dorina. Leibniz Institute for Zoo and Wildlife Research; Alemania
Author affiliation: Tsangaras, Kyriakos. Leibniz Institute for Zoo and Wildlife Research; Alemania
Author affiliation: Voirin, Bryson. Max Planck Institute For Ornithology; Alemania
Author affiliation: De Moraes Barros, Nadia. Universidad de Porto; Portugal
Author affiliation: Greenwood, Alex D.. Leibniz Institute for Zoo and Wildlife Research; Alemania. Freie Universitat Berlin; Alemania
Repository: CONICET Digital (CONICET). Consejo Nacional de Investigaciones Científicas y Técnicas