Summary of Research
Project: Isolation of Plant Genes and Promoters
Sub-project: Isolation, Cloning and Validation of Novel Genes and Promoters for Developing Insect resistant Crop Plants
Losses caused by insect pests are as old as plants themselves. Crop losses due to insect pests are estimated at 13% of all crop production by U.N. In the tropical countries like India, this problem is even more acute with higher incidence of insect activity. Synthetic pesticides have a strong impact on the human health and environment. Considerable progress has been made with developing transgenic crop plants expressing Bt endotoxins. However, there are no Bt genes affording protection against pests like Diabrotica, aphids, hoppers etc.
The promising area of research is return to an old approach with new technology i.e. the characterization of secondary plant products including lectins, protease inhibitor, amylase inhibitor etc. The insecticidal activity of these metabolites has been demonstrated against a wide range of insect pests i.e. Lepidopterans, Coleopterans, Orthopterans and Homopterans. By transferring single defensive gene from one plant species to another under the control of their own tissue specific promoters or constitutive promoters would impart resistance against insect pests.
At the Plant Gene Exploration Laboratory, we are isolating genes (lectins, protease inhibitors and amylase inhibitors) from the naturally occurring secondary metabolites of plant origin (legumes). These genes have an added advantage, as when transferred, they are correctly transcribed, translated and processed in a plant host. Also, most of the lectins and protease inhibitors are devoid of introns hence the cDNA clones can be exploited as well.
For an organism to be able to activate or turn off its own gene, each gene has its own molecular switch, called as promoter. They control gene expression in a tissue-dependent manner and according to the developmental stage of the plant. The transgenes driven by these type of promoters will only be expressed in tissues where the transgene product is desired, leaving the rest of the tissues in the plant unmodified by transgene expression. Unlike constitutive expression of genes, tissue-specific expression is the result of several interacting levels of gene regulation. As such, it is preferable to use promoters from homologous or closely related plant species to achieve efficient and reliable expression of transgenes in particular tissues. Even one gene can be placed under two tissue specific promoters and expressed at the desired site in the same plant. We at this lab are also trying to isolate tissue specific promoters and making transgenes using genes of secondary metabolites of plant origin.
Brassica juncea (Indian mustard) is an important source of edible oil cultivated in many countries across the globe. India is one of the largest rapeseed-mustard growing countries in the world, occupying the first position in Area and second position in production after China. A major constraint on productivity is an aphid species, Lipaphis erysimi which causes yield losses from 35.4 to 91.3%. The average yield loss has been reported at around 56.2%. The damage is mostly caused by nymphs and adults, which suck away the plant sap, often covering the entire surface of the shoots, floral buds and pods. The developed transgene including lectin gene under the control of tissue specific promoter is underway to control the damage cause by Aphids.
- Kansal, Rekha; Kumar, Akhilesh; Koundal, K.R. and Gupta, V.K. (2009) Lectins: Their Proposed Biological Functions In: Biotechnology: Cracking New Pastures Ed C P Malik and Aman Verma MD Publishers, New Delhi pp 1-18.
- Kuhar, Kalika; Kansal, Rekha; Koundal, Kirpa Ram and Gupta, Vijay Kumar (2010) Protease Inhibitors: Potential Defense Compounds in Plants. In: 'Genetic Engineering- A new hope for crop production & improvement', pp 1-55, Aavishkar Publishers & Distributors, Jaipur, India.
- Kansal, Rekha; Kuhar, Kalika; Gupta, Ram N; Gupta, Vijay K. and Koundal, K.R. (2008) Purification, characterization and evaluation ofinsecticidal potential of trypsin Inhibitor from mungbean (Vigna radiata L. Wilczek) seeds. Acta Physiol. Plant. 30:761-768.
- Kansal, Rekha; Kuhar, Kalika; Verma , Isha; Gupta, Ram N; Gupta, Vijay K. and Koundal, K.R. (2008) Improved and convenient method of RNA isolation from polyphenols and poly saccharide rich plant tissues. Ind. J. Exptl. Biol. 47: 842-845.
- Kansal, Rekha; Kuhar, Kalika; Gupta, Ram N; Gupta, Vijay K. and Koundal, K.R. (2008) Screening of Indegenous legumes for Trypsin inhibitor protein activity. Ind. J. Agri. Biochem. 21:54-56.
- Kansal, Rekha; Kumar, Mukesh; Kuhar, Kalika; Gupta, Ram N.; Subrahmanyam, Bhattiprolu; Koundal, Kirpa R. and Gupta,Vijay K. (2008). Purification and characterization of trypsin inhibitor from Cicer arietinum L. and its efficacy against Helicoverpa armigera. Braz. J. Plant Physiol., 20(4): 313-322.
- Sharma, Manju, Sahni, Rohini, Kansal, Rekha and Koundal, K. R. (2004). Transformation of oil seed mustard Brassica juncea (L) cv Pusa Jai Kissan with snow drop lectin gene. Ind. J. Biotechnology. 3: 97-102.
- Koundal, K. R., Dash, Prasanta K. and Kansal Rekha (2003). Plant defense proteins; Mechanism and potential of pest control through genetic manipulation. J. Plant Biology, 30 (2): 211-227.
- Qureshi, Insaf A., Dash P K, Kansal Rekha, Srivastava P.S. and Koundal K R (2003). Isolation and characterization of a lectin from seed of Cicer arietinum. Indian Journal of Plant Physiology. 8(2): 625-629.
- Datta Subhojit, Kansal Rekha and Koundal K.R. (2000). Construction and screening of cowpea (Vigna unguiculata L.) cDNA library for lectin genes. J. Plant Biochem. & Biotech. 6: 67-71.
- Koundal K.R., Mandaokar,A.D. and Kansal Rekha (2000). Isolation, cloning and characterization of storage protein genes of chickpea (Cicer arietinum L.) In Proceedings of the National Symposium on Biochemistry- Environment and Agriculture.
- Saha, Sanghamitra; Kansal, Rekha and Koundal K.R.(1996). Use of polymerase chain reaction in analyzing recombinant cDNA clones encoding storage proteins of chickpea (Cicer arietinum L.) Ind. J. Expt. Biol. 34:1019-1025.
- Kansal, Rekha; Ramkumar, T.P. and Koundal K.R. (1995). Construction of chickpea (Cicer arietinum L.) cDNA library in lambda gt11. Genetic Research and Education: Current Trends and the Next Fifty Years pp 1727-1732.
- Khitha, Seema; Kansal, Rekha and Koundal K.R.(1995). Isolation and characterization of genomic DNA of chickpea (Cicer arietinum L.) Plant Physiology and Biochemistry 22(1): 1-5.