Anastasia Shatilovich, Vamshidhar R. Gade, Martin Pippel, Tarja T. Hoffmeyer, Alexei V. Tchesunov, Lewis Stevens, Sylke Winkler, Graham M. Hughes, Sofia Traikov, Michael Hiller, Elizaveta Rivkina, Philipp H. Schiffer, Eugene W Myers, Teymuras V. KurzchaliaPlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"
<p style="text-align: justify;">Some organisms in nature have developed the ability to enter a state of suspended metabolism called cryptobiosis1 when environmental conditions are unfavorable. This state-transition requires the execution of complex genetic and biochemical programs1,2,3, that enables the organism to survive for prolonged periods. Recently, nematode individuals have been reanimated from Siberian permafrost after remaining in cryptobiosis. Preliminary analysis indicates that these nematodes belong to the genera Panagrolaimus and Plectus4. Here, we present precise radiocarbon dating indicating that the Panagrolaimus individuals have remained in cryptobiosis since the late Pleistocene (~46,000 years). Phylogenetic inference based on our genome assembly and a detailed morphological analysis demonstrate that they belong to an undescribed species, which we named <em>Panagrolaimus n.</em> sp. Comparative genome analysis revealed that the molecular toolkit for cryptobiosis in <em>Panagrolaimus n.</em> sp. and in <em>C. elegans</em> is partly orthologous. We show that biochemical mechanisms employed by these two species to survive desiccation and freezing under laboratory conditions are similar. Our experimental evidence also reveals that <em>C. elegans</em> dauer larvae can remain viable for longer periods in suspended animation than previously reported. Altogether, our findings demonstrate that nematodes evolved mechanisms potentially allowing them to suspend life over geological time scales. </p>
Cryptobiosis, Pleistocene, C. elegans, Permafrost, Suspended animation
Bob Goldstein, bobg@email.unc.edu, Marie ann felix, felix@bio.ens.psl.eu, Asher cutter, asher.cutter@utoronto.ca, Paul de ley, paul.deley@ucr.edu, Davide Pisani, Davide.Pisani@bristol.ac.uk, Tim Barraclough, tim.barraclough@zoo.ox.ac.uk
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