CaenorhabditiselegansTolerates Hyperaccelerations up to 400,000 x g

Abstract

One of the most important laboratory animal species is the nematode Caenorhabditis elegans, which has been used in a range of research fields such as neurobiology, body development, and molecular biology. The scientific progress obtained by employing C. elegans as a model in these areas has encouraged its use in new fields. One of the new potential applications concerns the biological responses to hyperacceleration stress (g-force), but only a few studies have evaluated the response of multicellular organisms to extreme hypergravity conditions at the order of magnitude 10 x g, which is the theorized force experienced by rocks ejected from Mars (or similar planets). Therefore, we subjected the nematode C. elegans to 400,000 x g (equivalent to that force) and evaluated viability, general morphology, and behavior of C. elegans after exposure to this stress. The metabolic activity of this nematode in response to the gravitational spectrum of 50-400,000 x g was also evaluated by means of the MTT assay. Surprisingly, we found that this organism showed no decrease in viability, no changes in behavior and development, and no drastic metabolic depression after hyperacceleration. Thus, we demonstrated for the first time that this multicellular research model can withstand extremely high g-forces, which prompts the use of C. elegans as a new model for extreme hypergravity. Key Words: Caenorhabditis elegans-Hypergravity-Ultracentrifugation-Acceleration-Panspermia-Astrobiology. Astrobiology 18, 825-833.

Nicotiana benthamiana seeds tolerate hyperaccelerations up to 400,000 x g

“…The findings of Kwon and Oono (1992 a,b), along with others, reporting survival of organisms submitted to g-forces ≥105 x g (Deguchi et al, 2011;Gao et al, 2013;Montgomery et al, 1963;Souza and Pereira, 2018;Yoshida et al, 1999), call into attention that a special type of tolerance, to extreme hyperaccelerations, may have been largely ignored until now.…”

“…To our knowledge, the only plant species tested so far, as an entire structure instead of detached parts, is Oryza sativa (rice) (Kwon et al, 1992;Kwon and Oono, 1992), whose seeds (i.e., the embryo and accessory tissues) were able to germinate after 450,000 x g. More recently, we have revealed that two free-living nematode species are able to withstand 400,000 x g (Souza et al, 2017;Souza and Pereira, 2018). Here, we decided to evaluate the effects of exposing seeds of the plant model Nicotiana benthamiana to 400,000 x g, followed by analyses on their capabilities to germinate.…”

The First Interstellar Astronauts Will Not Be Human

“…Microgravity research on Earth requires setups such as drop tubes and parabolic flights, whereas hypergravity experiments require only a centrifuge, which can simulate gravitational accelerations within the range of our spacecraft (10 4 to 10 6 g). Tardigrade species are adversely affected by hypergravity but are more resistant than larger organisms, such as the fruit fly, D. melanogaster, while species like C. elegans fare quite well under hyperacceleration [18,19,20]. However, tardigrades can be launched in a cryptobiotic state, with the hope that this will mitigate deleterious acceleration-dependent effects of hypergravity on their survival rate [20].…”

Panagrolaimus superbus tolerates hypoxia within Gallium metal cage: implications for the understanding of the phenomenon of anhydrobiosis

“…Notoriously, in the dry state, anhydrobiotic organisms exhibit polyextremotolerance, i.e. tolerance to harsh conditions for life, such as high and low temperatures (from −273°C to +151°C) (Rahm, 1923;Becquerel, 1950); ionizing radiation (Keilin, 1959); high hydrostatic pressures (Seki and Toyoshima, 1998); vacuum (Rebecchi et al, 2009); and hyperacceleration (Souza and Pereira, 2018). Biological activity is fully restored after rehydration.…”