Historical uranium (U) mining operations resulted in the contamination of large areas, including surface waters. The effects of U on the freshwater plant Lemna minor have been investigated, although they were mainly studied on individual and cellular level. Sequencing of the L. minor genome and transcriptome gives possibilities to study the effects on molecular level. The aim of this study is to select and validate potential U-biomarker genes that can possibly predict the effects of U exposure on population level as well as on ecosystem level. Since organisms growing in contaminated waters are not only exposed to U, but also to multiple co-contaminants, it is necessary to find biomarkers that react specifically to U and not to the co-contaminants. L. minor plants were exposed to 0, 2 or 10 μM U in combination with an environmentally relevant metal mixture consisting of Cu, Ni, Zn and Pb. Plants were exposed during 1, 4 or 7 days. Expression levels of 10 primers for potential U-biomarkers genes were tested using real-time qPCR. A comet assay on L. minor was optimized as a second potential biomarker for DNA damage. The earlier discovered primer 33 could be validated as biomarker for U exposure. In addition, based on gene expression analysis two new U-biomarkers were selected within this project, i.e. primer 48 and primer 52, since their related genes reacted specifically to U already after 4 days of exposure and to the lowest tested U concentration (2 μM). However, further investigations and validation is necessary.
|State||Published - 21 Jun 2019|