Development of a non-lethal method for evaluating transcriptomic endpoints in Arctic grayling (Thymallus arcticus).
With increases in active mining and continued discharge associated with former mine operations, evaluating the health of watersheds in the Canadian Yukon Territory is warranted. Current environmental assessment approaches often employ guidelines established using sentinel species not relevant to Arctic monitoring programs. The present study focused on the successful development of a quantitative real-time polymerase chain reaction (qPCR) assay directed towards the indigenous Arctic grayling (Thymallus arcticus) and examines the feasibility of using non-lethal sampling from the caudal fin as a means for evaluation of mRNA abundance profiles reflective of environmental conditions. In a proof of concept study performed blind, qPCR results from animals in an area with elevated water concentrations of cadmium (Cd) and zinc (Zn) and higher body burdens of Cd, Zn, and lead (Pb) were compared to a reference location in the Yukon Territory. Lower condition factor and a higher abundance of hepatic and caudal fin gene transcripts encoding the metallothionein isoforms (mta/mtb), in addition to elevated heat shock protein 70 (hsp70) and catalase (cat) mRNAs in liver, were observed in fish from the test site. The strong positive correlation between metal body burden and caudal fin mta/mtb mRNA abundance demonstrates a high potential for use of the Arctic grayling assay in non-lethal environmental monitoring programs.
Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, STN CSC, Victoria, BC, Canada V8W 3P6. Electronic address: veldhoen@uvic.ca.
Nik
N
Veldhoen
Water Resources Branch, Environment Yukon, Government of Yukon, Box 2703 (V-310), Whitehorse, Yukon, Canada Y1A 2C6. Electronic address: Jean.Beckerton@gov.yk.ca.
Jean E
JE
Beckerton
Fisheries and Oceans Canada, 100-419 Range Road, Whitehorse, Yukon, Canada Y1A 3V1. Electronic address: Jody.Mackenzie-Grieve@dfo-mpo.gc.ca.
Jody
J
Mackenzie-Grieve
Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, STN CSC, Victoria, BC, Canada V8W 3P6. Electronic address: mitchs@uvic.ca.
Mitchel R
MR
Stevenson
Water Resources Branch, Environment Yukon, Government of Yukon, Box 2703 (V-310), Whitehorse, Yukon, Canada Y1A 2C6. Electronic address: Bob.Truelson@gov.yk.ca.
Robert L
RL
Truelson
Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, STN CSC, Victoria, BC, Canada V8W 3P6. Electronic address: chelbing@uvic.ca.
Caren C
CC
Helbing
D000818:Animals; D004784:Environmental Monitoring / Q000379:methods*; D005786:Gene Expression Regulation / Q000187:drug effects; D008099:Liver / Q000187:drug effects; D019216:Metals, Heavy / Q000633:toxicity*; D008906:Mining; D012487:Salmonidae / Q000235:genetics*; D013312:Stress, Physiological / Q000187:drug effects*; D059467:Transcriptome / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
Fish; Mining; Non-lethal assay; Quantitative real time polymerase chain reaction; Sentinel species; Wildlife conservation