Project description:Characterization of Middle Pleistocene rhinoceros proteins and the phylogenetic relationships between extinct and extanct rhinoceros was investigated by obtaining ancient protein data for two extinct rhinoceros genera (Coelodonta antiquitatis and Stephanorhinus sp.).
2017-02-02 | PXD005534 | Pride
Project description:Whole genome sequencing of Galapagos giant tortoises
Project description:The living tree sloths Choloepus and Bradypus are the only remaining members of Folivora, a major xenarthran radiation that occupied a wide range of habitats in many parts of the western hemisphere during the Cenozoic, including both continents and the West Indies (Antilles). To date, molecular evidence has played only a minor role in folivoran systematics, as most recently-extinct species lived in places not conducive to DNA preservation. Here we utilize collagen sequence information to assess the relationships of tree sloths to a large sample (13 species) of extinct Quaternary folivorans.
Project description:Here we show the potential of proteins preserved in Pleistocene eggshell for addressing a longstanding controversy in human and evolution: the identity of the extinct bird that laid the eggs which were exploited by Australia’s first inhabitants. The eggs had been originally attributed to the iconic extinct flightless Genyornis newtoni, and subsequently dated to before 50 ±5 ka by Miller et al. (2016). This was taken to represent the extinction date for this endemic megafaunal species and thus implied a role of humans in its demise. A contrasting hypothesis, according to which the eggshell was laid by a large megapode (mound-builder), would therefore acquit humans of their responsibility in the extinction of Genyornis. Ancient protein sequences were reconstructed and used to assess the evolutionary proximity of the undetermined eggshell to extant birds, rejecting the megapode hypothesis. Ancient DNA could not be retrieved from these highly degraded samples, but morphometric data supported the attribution of the eggshell to Genyornis. When used in triangulation to address well-defined hypotheses, palaeoproteomics is a precious tool for reconstructing the evolutionary history of extinct and extant species. Here we show that the identification of Genyornis eggshell implies a more nuanced understanding of the modes of interactions between humans and their environment.
Project description:High resolution Mass Spectrometry and Peptides identification uncovered ancestral giant insect viruses motifs within Histone-4 peptides in human liver cells. These peptides did not match any human sequence. This finding consolidates the dogma that molecular patterns are universal and suggests that metazoan cellular structures possibly share an evolutionary link with ancient giant viruses.
Project description:During a compatible interaction, root-knot nematodes (Meloidogyne spp.) induce the redifferentiation of root cells into multinucleate nematode feeding cells giant cells. These hypertrophied cells result from repeated nuclear divisions without cytokinesis, are metabolically active and present features typical of transfer cells. Hyperplasia of the surrounding cells leads to formation of the typical root gall. We investigate here the plant response to root-knot nematodes.
