Online Event
September 01-03, 2022 | Online Event
GPMB 2022

A bZIP transcription factor from Picrorhiza kurrooa modulates the expression of terpenoid biosynthesis genes in Nicotiana Benthamiana

Tanvi Sharma, Speaker at Plant Conferences
CSIR-Institute of Himalayan Bioresource Technology , India
Title : A bZIP transcription factor from Picrorhiza kurrooa modulates the expression of terpenoid biosynthesis genes in Nicotiana Benthamiana


Basic leucine zipper (bZIP) transcription factors are DNA-binding proteins which recognize the ACGT motif in the promoter region of genes and regulate their expression. bZIP TFs play significant roles in plant growth and development, defense, metabolic regulation and responses to environmental stresses. Till now, there is no report on the cloning and characterization of bZIP transcription factors in Picrorhiza kurrooa, an endangered medicinal herb of north western Himalayas. The medicinal properties of P. kurrooa are attributed to picrosides synthesized by isoprenoid pathway. The promoters of regulatory genes 1-deoxy-D-xylulose-5-phosphate synthase (pkdxs) and 3-hydroxy-3-methylglutaryl coenzyme A reductase (pkhmgr) of the pathway contain ACGT cis-acting elements (bzip motifs) at different locations. In this study, we showed the functionality of ACGT motifs by electrophoretic mobility shift assay (EMSA). Full length bZIP gene was cloned through RACE method. In silico analysis revealed pkbZIP contained a highly conserved bZIP domain profile (N-X7-R/K- X9-L-X6-L-X6-L). Quantitative real time PCR (RT-qPCR) was used to analyze tissue-specific expression and the expression changes in response to temperature and continuous light and dark conditions. The gene expression corroborated with the picroside (active medicinal component of the plant) content at tissue specific level, under light conditions and at 15 °C (temperature favouring picroside accumulation). Transient overexpression in tobacco modulated the expression of genes involved in terpenoid biosynthesis in tobacco suggesting in planta functionality of pkbZIP. Collectively, data suggested that pkbZIP might prove as potential candidate for metabolic engineering programs aimed at enhancing picrosides biosynthesis in P. kurrooa.


Dr. Tanvi Sharma graduated in Biotechnology from Panjab university, Chandigarh in the year 2008. She obtained her Masters degree in Biotechnology from Panjab university, Chandigarh in year 2010. She then joined research group led by Dr. Girish Sahni at Institute of microbial technology, Chandigarh and worked on engineering peptides and proteins for new generation therapies. Thereafter she joined research group led by Dr. Madhu Khullar at Post Graduate Institute of Medical Education and Research, Chandigarh and worked on detection of genetic mutations by genome sequencing in cardiomyopathy patients. She obtained her PhD degree from Institute of Himalayan Bioresource Technology, Palampur in the year 2021 wherein she sequenced genome of an endangered medicinal herb, Picrorhiza kurrooa. Thereafter she joined as “Senior Project Associate” at the same institute in the project entitled “CSIR Floriculture Mission” wherein she is involved in developing transcriptomic resources for floriculture crops.She has published two papers as first author in SCI journals.