Multi-walled Carbon Nanotubes Functionalized Effect on Expression of TXS and DBTNBT Genes Involved in Paclitaxel Biosynthetic Pathway in Taxus baccata

The frequency of secondary metabolites is often less than 1% of total carbon in plants, therefore, biotechnologists have focused on cell culture, tissue and plant organ as an alternative way for production of secondary metabolites. Nowadays, using elicitors is one of the effective approaches to increase productivity of secondary metabolites in plants cell cultures. Abiotic elicitors contain metal ions, inorganic compounds, nanoparticles, etc. Nanoparticles are able to carry metabolites and transfer oligonucleotide molecules in plant cells. In this study, the effect of multi-walled carbon nanotube functionalized with carboxyl was evaluated on gene expression alteration of two genes involved in paclitaxel biosynthesis pathway in Taxus baccata cell suspension. Cell suspension was treated by multi-walled nanotube functionalized on 12th day of cells growth at Nano carbon concentrations of 100 and 250 mg l-1. The levels of gene expression were measured by qRT-PCR after 4 and 72 h in compare to control. Our results clearly showed that the expression level of TXS gene in upstream of paclitaxel biosynthetic pathway was increased significantly at 100 mg l-1about 2.1-fold 4 h after treatment. The expression level of this gene was also increased about 2.4 and 7.2-fold 72 h after the treatment at 100 and 250 mg l-1 concentrations, respectively. On the other hand the expression level of DBTNBT gene in downstream pathway was found to have increased about 6.9 and 7.8-fold 72 h after the treatment at 100 and 250 mg l-1 concentrations, respectively. From these results, we could conclude that the intracellular paclitaxel production have increased with metabolite passing through the pores in cell wall that created by multi-walled carbon nanotube.

Keywords:

Taxus baccata , Paclitaxel , Multi-walled Carbon Nanotube Functionalized , TXS , DBTNBT