Abstract
BackgroundOrnithine (Orn) plays an essential role in the metabolism of plant cells through incorporation in polyamines biosynthesis, the urea cycle and nitrogen metabolism. Physiological response of the plant cells to its two enantiomers have not been widely investigated yet.ObjectivesThis study aimed to evaluate effect of ornithine enantiomers on expression of certain polyamine (PAs) biosynthetic genes in tobacco cells.Materials and MethodsSuspension-cultured tobacco cells were treated with different concentrations of L- and D- Orn for 24 h. Cell viability was assayed by Evans Blue and hydrogen peroxide content. The changes of gene expression were analyzed by semi-quantitative RT-PCR.ResultsExogenous D-Orn resulted in enhancement of expression of genes involved in Orn, arginine and S-adenosyl methionine metabolism. Additionally, exogenous D-Orn treatment resulted in sustained viability of cultured tobacco cells and normal levels of hydrogen peroxide were maintained. Supplied L-Orn increased the hydrogen peroxide level and lowered viability of cells. Treatment with L-Orn had a negative effect on the transcript levels for most analyzed PA-related genes. It was also illustrated that transcription of putrescine methyl transferase, key enzyme for nicotine production, was highly upregulated by L-Orn.ConclusionsBased on the results, D-Orn was shown to have a stereo-selective function in regulation of the PAs-related genes.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call