Hypergravity hinders axonal development of motor neurons in Caenorhabditis elegans
- Published
- Accepted
- Subject Areas
- Developmental Biology, Genetics, Neuroscience
- Keywords
- C. elegans, gravity, motor neurons, axon, space flight
- Copyright
- © 2016 Kalichamy et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. Hypergravity hinders axonal development of motor neurons in Caenorhabditis elegans. PeerJ Preprints 4:e2363v1 https://doi.org/10.7287/peerj.preprints.2363v1
Abstract
As space flight becomes more accessible in the future, humans will be exposed to gravity conditions other than our 1G environment on Earth. Changes in physiology and anatomy in altered gravity conditions have long been observed, especially the loss of muscle mass during long-term space habitation, the reason for which is not fully understood. Although much effort has gone into studying the effects of gravity in muscle physiology, its effect on the development of neurons has not been thoroughly assessed. Using the nematode model organism Caenorhabditis elegans, we examined changes in response to hypergravity in the development of the 19 GABAergic DD/VD motor neurons that innervate body muscle. We found that a high gravity force above 10G significantly increases the number of animals with defects in the development of axonal projections from the DD/VD neurons. We showed that a critical period of hypergravity exposure during the embryonic/early larval stage was sufficient to induce defects. While characterizing the nature of the axonal defects, we found that in normal 1G gravity conditions, DD/VD axonal defects occasionally occurred, with the majority of defects occurring on the dorsal side of the animal and in the mid-body region, and a significantly higher rate of error in the 13 VD axons than the 6 DD axons. Hypergravity exposure increased the rate of DD/VD axonal defects, but did not change the distribution or the characteristics of the defects. Our study demonstrates that in addition to gravity’s effects on muscle development, gravity can also impact motor neuron development.
Author Comment
This is a submission to PeerJ for review.