Genomic response of the nematode Caenorhabditis elegans to spaceflight

Abstract

On Earth, it is common to employ laboratory animals such as the nematode Caenorhabditis elegans to help understand human health concerns. Similar studies in Earth orbit should help understand and address the concerns associated with spaceflight. The "International Caenorhabditis elegans Experiment FIRST" (ICE FIRST), was carried out onboard the Dutch Taxiflight in April of 2004 by an international collaboration of laboratories in France, Canada, Japan and the United States. With the exception of a slight movement defect upon return to Earth, the result of altered muscle development, no significant abnormalities were detected in spaceflown C. elegans. Work from Japan revealed apoptosis proceeds normally and work from Canada revealed no significant increase in the rate of mutation. These results suggest that C. elegans can be used to study non-lethal responses to spaceflight and can possibly be developed as a biological sensor. To further our understanding of C. elegans response to spaceflight, we examined the gene transcription response to the 10 days in space using a near full genome microarray analysis. The transcriptional response is consistent with the observed normal developmental timing, apoptosis, DNA repair, and altered muscle development. The genes identified as altered in response to spaceflight are enriched for genes known to be regulated, in C. elegans, in response to altered environmental conditions (Insulin and TGF-beta regulated). These results demonstrate C. elegans can be used to study the effects of altered gravity and suggest that C. elegans responds to spaceflight by altering the expression of at least some of the same metabolic genes that are altered in response to differing terrestrial environments.

The behavioural-driven response of the Drosophila imago transcriptome to different types of modified gravity

“…In Drosophila, Hsp70 seems to be a mediator of the aging-protective effect induced by mild hypergravity [28], a relation also highlighted in mammals [33,34]. A preliminary genome scale analysis of spaceflight response in nematodes [6] has also detected stress links, though this is the first time that microgravity conditions have been linked to a genome-scale stress related response in Drosophila.…”

“…Although previous investigations [1][2][3][4][5] have not yet led to a consensus on how the environment in spacecraft affects the genetic behaviour of living organisms, studies of the overall transcriptome response to microgravity of some species [6], including Drosophila [7], have revealed interesting effects.…”

Reproductive and Locomotory Capacities of Caenorhabditis elegans Were Not Affected by Simulated Variable Gravities and Spaceflight During the Shenzhou-8 Mission

“…For example, earlier studies have suggested that cosmic radiation can cause an increased rate of mutations in C. elegans (Nelson et al, 1994;Hartman et al, 2001), but no significant difference in mutation rate was found in another spaceflight study (Zhao et al, 2006). Also, a decreased expression of myogenic transcription factors and myosin heavy chains has been detected, but no significant abnormality in muscle development was observed in C. elegans after spaceflight (Higashibata et al, 2006;Selch et al, 2008). Further, little information is available on the alteration of reproductive capacity and locomotory ability of C. elegans in response to variable gravities and spaceflight.…”

Spaceflight and Ageing: Reflecting on <b><i>Caenorhabditis elegans</i></b> in Space

“…Consequently, C. elegans remains at the forefront of animals used in experiments to understand how the genome controls health. Other experiments with this worm have led to the discovery of programmed cell death, the phenomena of gene silencing by RNA interference, the discovery of microRNAs, evolutionarily conserved genes that contribute to maximal lifespan [12], and a reproducible genomic response to spaceflight [13] (and subsequent flights).…”