title: Time Matters in Ecotoxicological Sampling Due to Circadian Rhythm.
abstract: As in general, technological inventions also drive the development in the field of toxicology and ecotoxicology. In the past decade, gene expression analysis has become a universally applied technology allowing many insights into toxicological pathways of environmental contaminants. Due to the novel technologies, including quantitative determination of mRNA by quantitative reverse transcription analysis (qRT-PCR), and semiquantitative methods, such as microarrays and RNA-sequencing technologies, toxicological profiles of contaminants could be identified. For instance, gene expression analysis of genes associated with the hypothalamic-pituitary-gonadal axis (HPG axis) in fish had become a conventional end point for endocrine disrupting chemicals. While these gene expression data provide novel insights into identifying potential toxicological end points and molecular mechanisms, often not enough attention is given to the question of mRNA stabilities and reliabilities of transcriptional data, in particular when links to physiological effects are difficult to make. A crucial factor in this issue is the endogenous circadian oscillations of genes during sampling.
authors.affiliation: University of Applied Sciences and Arts Northwestern Switzerland (FHNW) , School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz, Switzerland.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: University of Applied Sciences and Arts Northwestern Switzerland (FHNW) , School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz, Switzerland.|Swiss Federal Institute of Technology (ETH Zürich) , Institute of Biogeochemistry and Pollution Dynamics, Department of Environmental System Sciences, CH-8092 Zürich, Switzerland.
authors.forename: Karl
authors.initials: K
authors.lastname: Fent
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology*; D054750:Ecotoxicology / Q000379:methods*; D052244:Endocrine Disruptors / Q000633:toxicity; D004703:Endocrine System / Q000187:drug effects; D029941:Fish Proteins / Q000235:genetics*; D005399:Fishes / Q000378:metabolism / Q000502:physiology*; D020869:Gene Expression Profiling; D005819:Genetic Markers; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors
chemical_list: D052244:Endocrine Disruptors; D029941:Fish Proteins; D005819:Genetic Markers; D012333:RNA, Messenger