Transcription of genes associated with nickel resistance induced by different doses of nickel nitrate in Quercus rubra. Issue 9 (21st October 2019) - Djeukam, Charnelle L.
ABSTRACT: Knowledge of the mechanism of genetic resistance to nickel (Ni) toxicity in red oak ( Quercus rubra ) is limited. The main objective of the present study was to evaluate the level of transcription of genes associated with nickel resistance in Q. rubra plants exposed to different doses of potassium nitrate and nickel nitrate. All the Q. rubra genotypes screened were highly resistant to nickel nitrate and potassium nitrate. An unexpected high level of transcription of ( ACC ) deaminase was induced in leaves by the low dose of potassium nitrate (150 mg/kg). This gene response decreased as the dose was increased to reach the lowest level at the high dose (1600 mg/kg). On the other hand, nickel induced significantly higher level of ACC deaminase transcription only for 1600 mg/kg of nickel nitrate. This transcription was higher in leaves compared to roots. For serine acetyltransferase (SAT) gene, the transcription was higher in roots than in leaves. Surprisingly, potassium nitrate (a common plant fertiliser) induced an upregulation of nicotianamine synthase (NAS3) gene in leaves of samples exposed to 150 mg/kg dose and a downregulation for the 1600 mg/kg treatment. An opposite trend attributed to nickel was observed with nickel nitrate treatments.