Nickel induces changes in expression of genes encoding 1-aminocyclopropane-1-carboxylic acid deaminase and glutathione reductase in Picea glauca

ABSTRACT

Nickel (Ni) in trace amounts is important in plant nutrition; it can also be toxic in excess. The objective of this study was to determine if nickel affects gene expression in white spruce (Picea glauca). Nickel toxicity was assessed by treating seedlings with an aqueous solution of nickel nitrate salt [Ni(NO₃)₂] at different doses (150, 800 mg/kg, and 1600 mg/kg) using a completely randomised design. Expression of the genes encoding 1-aminocyclopropane-1-carboxylic acid deaminase (ACCD) and glutathione reductase (GR) in roots and needles were investigated using RT qPCR analysis. No damage was observed on P. glauca seedlings. This study revealed that Ni induces an upregulation of ACCD at low and high doses tested in roots. Nickel treatments resulted in a downregulation of GR at low dose (150 mg/kg) in needles and an upregulation at low and high doses in roots. This suggests that the low level of bioavailable nickel in mining sites in Ontario and other regions can trigger changes in gene expression. The results also show that potassium nitrate induces a significant effect on gene expression in P. glauca mostly at high concentrations.

KEYWORDS:

• Gene expression
• metal resistance
• nickel toxicity
• RT-qPCR
• white spruce (Picea glauca)

Acknowledgements

Technical support of Dr. Paul Michael is greatly appreciated. Thanks to Marc Hebert, College Boreal, Sudbury for providing the seedlings used in this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work received financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC), Canada [Grant numbers NSERC-CRD-470535-14, NSERC-RGPIN-5323-4].

Notes on contributors

Meagan Boyd

Meagan Boyd is a M.Sc. student in the Department of Biology at Laurentian University, Ontario, Canada.

Kabwe K. Nkongolo

Kabwe Nkongolo is a Professor of Genetics in the Department of Biology and the Biomolecular Science Program at Laurentian University in Sudbury (Ontario, Canada). He is the Coordinator of the Environmental Genetics and Biotechnology Research Laboratory. He runs a very productive research program with a focus on genetic adaptation to soil metal contamination in plants.