| description |
Fish have been highly exposed to radiation in freshwater systems after the Chernobyl Nuclear Power Plant (NPP) accident in 1986, and in freshwater and marine systems after the more recent Fukushima NPP accident in 2011. In the years after the accident the radioactivity levels rapidly declined due to the short half-life of some radionuclides and the decay of long-lived radionuclides. A recent study showed that, after several generations of exposure to environmental radiation at Chernobyl, perch displayed a delay in the maturation of gonads in the most contaminated lakes. Some undeveloped phenotypes were also observed in two of the three contaminated lakes. In order to gain insights into the long term effect of environmental low dose radiation on gonad development, a high throughput transcriptomic approach, including a de novo assembly, was applied to different gonad phenotypes of perch: normal from reference lake, apparently normal from low contaminated lake and apparently normal and undeveloped from more highly contaminated lakes. |
| abstract |
Fish have been highly exposed to radiation in freshwater systems after the Chernobyl Nuclear Power Plant (NPP) accident in 1986 and in freshwater and marine systems after the more recent Fukushima NPP accident in 2011. In the years after the accident, the radioactivity levels rapidly declined due to radioactive decay and environmental processes, but chronic lower dose exposures persisted. To gain insights into the long-term effects of environmental low dose radiation on fish ovaries development, a high-throughput transcriptomic approach including a de novo assembly was applied to different gonad phenotypes of female perch: developed gonads from reference lakes, developed/irradiated from medium contaminated lake, and both developed/irradiated and undeveloped from more highly contaminated lakes. This is the most comprehensive analysis to date of the gene responses in wildlife reproductive system to radiation. Some gene responses that were modulated in irradiated gonads were found to be involved in biological processes including cell differentiation and proliferation (ggnb2, mod5, rergl), cytoskeleton organization (k1C18, mtpn), gonad development (nell2, tcp4), lipid metabolism (ldah, at11b, nltp), reproduction (cyb5, cyp17A, ovos), DNA damage repair (wdhd1, rad51, hus1), and epigenetic mechanisms (dmap1). Identification of these genes provides a better understanding of the underlying molecular mechanisms underpinning the development of the gonad phenotypes of wild perch and how fish may respond to chronic exposure to radiation in their natural environment, though causal attribution of gene responses remains unclear in the undeveloped gonads. |
Gene
RNA