Cloning and characterization of defense related genes from Piper colubrinum by subtractive cDNA approach

Piper colubrinum is an exotic wild species of Piper which shows high degree of resistance to many devastating diseases of cultivated pepper including foot rot and slow decline diseases caused by Phytophthora capsici and Rhadopholus similes, respectively.It has good potential as donor plant in breeding programmes for the improvement of the cultivated species, Piper nigrum. Biotechnological approaches such as molecular resistance breeding would provide immense potential for the improvement of cultivated black pepper. Salicylic acid (SA), the phenyl propanoid derivative plays a key role in disease resistance and has been implicated as a signal in systemic acquired resistance (SAR). Our group is currently working on identifying and characterizing SA- induction-specific defense related genes from P. colubrinum by suppression subtractive hybridization (SSH) technique. Only limited reports are available for Piper colubrinum and this is the first report of a molecular study for elucidation of the resistance mechanism operational in the plant.

Cloning and characterization of an anti fungal gene osmotin from resistant wild pepper

Osmotin an antifungal PR-5 gene homologue from P.colubrinum has been cloned full length and work is in progress to express and purify the recombinant protein and analyse the antifungal activity. Two isoforms of osmotin, which were differentially expressed in response to the defense signaling molecule, salicylic acid have been sequence characterized. The larger form of the gene is 693 bp long, encoding a 21.5 kDa protein. The other form comprises of a 543 bp long coding sequence which code for a smaller protein of 16.4kD. A notable feature of the smaller form was a prominent internal deletion of 150 bp besides certain point mutations. Cloned isoforms of osmotin from resistant species could be candidates for molecular breeding for the improvement of black pepper as well as for the study of structure based mechanism of antifungal activity attributed to PR-5 family. This and other candidate genes identified from the resistance source could be utilized for the genetic improvement of pepper and other important crop plants.

Optimization of Recombinant Human Therapeutic Granulocyte Colony Stimulating Growth Factor (GCSF) Production in Tobacco

Colony stimulating factors are a family of proteins that regulate the proliferation and differentiation of the progenitor cells for granulocytes and macrophages. Human Granulocyte colony stimulating factor (r hGCSF) is a cytokine produced by monocytes, macrophages and other immune cells. GCSF is now therapeutically used in the treatment of transient phases of leucopenia that may follow chemotherapy or radiotherapy. It is also used to enhance immune system deficiency caused by diseases such as AIDS.
Plants represent a suitable alternative to other host systems like mammalian cell cultures, and prokaryotic system because of the advantageous economics of growing plant crops. Plant cell derived proteins are likely to be safer for human use since plant cell contaminants and viruses are not pathogenic to humans. Through genetic engineering, plants can now be used to produce pharmacologically active proteins, including mammalian antibodies, blood product substitutes, vaccines, hormones, cytokines, and many other therapeutic agents.
For green matter production, Tobacco is well suited as a factory for recombinant protein production because it is easy to alter genetically and produces great deal of biomass. It is a non food, non feed crop and has no chances of entering the food chain.