In silico and molecular cloning studies on the curcin isoforms in Jatropha (Jatropha curcas L.)

Abstract

The biodiesel crop Jatropha (Jatropha curcas L.) has gained world-wide importance during the last few decades. Itsnon-edible seed oil could be converted to biofuel for blending with fossil fuels. A number of important metabolites of Jatropha have significant commercial importance as the contents could be used in making cosmetics, soaps, fertilizers and lubricants. Curcins, a group of toxic proteins are present in Jatropha seeds and other tissues. They are basically Ribosome inactivating proteins (RIP) which render cytotoxic effects. Interestingly, curcin proteins have some pharmacological importance. Since, curcin proteins could be used as anti-tumor, anti-HIV, antiviral and immunosuppressive agents. The present study focused mainly on two curcin isoforms namely Curcin 2A (GenBank protein id: ABZ04128.1) and Curcin precursor (GenBank protein id: AAL86778.1). Several facile modern bioinformatics tools have been employed to generate data comprising of searching protein motifs, 3-D modeling, phylogenetic tree, Ramachandran plot and some other important attributes. Many of these features as obtained in this study were not reported earlier. Good quality RNA was isolated from different Jatropha tissues namely leaf, seed kernel and seed pericarp. RT-PCR approach was adopted using total RNA and oligo (dT) primer. The size of each amplicon was ~1.0 kb. A number of putative Curcin 2A specific cDNA clones were obtained using total RNA from different Jatropha tissues. The putative cDNA clones in pMD 20-T vector were partially characterized by restriction analysis and PCR. These cDNA clones will be sequenced for further use in recombinant protein expression. sequenced prior to undertake molecular approaches for recombinant expression of the individual curcin isoforms.