Research Groups
Plant Biology: Plant Molecular Biology
Research Interests and Description
Staff Research Scientist: Suresh Nair, PhD
Group Leader: Sunil Kumar Mukherjee
Research Interests
Biotic stress, insect-plant interaction, gene expression, crop improvement, abiotic stress.
Research Interests
The Group’s major interest is understanding insect-plant interaction. The Asian rice gall midge (Orseolia oryzae; Order Diptera, Family Cecidomyiidae) is an important insect pest of rice and is responsible for causing considerable yield and monetary loss to farmers in India, Africa, South East Asia and neighbouring countries. Another reason the gall midge is such a serious pest is that there exist many biotypes rendering resistance genes in rice ineffective after deployment. Genetically, it has been shown that resistance against gall midge, in most cases, is governed by a single, dominant gene in rice. Earlier, we mapped and tagged gall midge resistance genes in rice Gm2, Gm4, Gm7 and Gm8 and were also the first to develop a PCR-based marker aided selection (MAS) system for these genes.
Current interests are to gain insights into the molecular basis/bases of gall midge-rice interaction. In the case of rice gall midge it is known that, in all probability, the initial interaction between the pest and the host determines whether the host will succumb to the midge or be able to resist. During the infestation process and subsequent feeding on the host, the larvae inject substance(s) into the host. Therefore, as in the case of the pathogenic bacteria and fungi, these products could be determinants of the avirulence/virulence phenomenon. Extending this idea further, the genes that encode these molecules could be determinants for the gall midge biotypes. Further, the genes that encode such molecules could be those that encode secreted salivary gland proteins (SSGPs), which in turn could be determinants of gall midge virulence/avirulence. Characterizing genes that encode SSGPs will give us a handle on studying this interaction as well as valuable insights into the process of infestation of rice by this pest.
Recently, we have cloned, screened and characterized genes from the rice gall midge that are putative SSGPs. Using quantitative PCR we have shown that some of these are overexpressed when gall midge larvae are feeding on susceptible hosts (compatible interaction) while others overexpress in larvae feeding on resistant hosts (incompatible interaction). We are also in the process of studying the rice gall midge transcriptome to get a better understanding of insect defence and survival in the host plant. This will also be used to generate an invaluable database for conducting various studies involving rice-gall midge interaction. We collaborate on screening subtracted cDNA libraries for identifying genes that show differential expression during compatible and incompatible interactions of the gall midge with its host.
The Group has been involved in characterising and studying plant gene expression and the important roles these play in the cellular activities of the plants, especially when exposed to abiotic stress.
Recent Publications
Sinha, D.K., Bentur, J.S., Nair, S. 2011. Compatible interaction with its rice host leads to enhanced expression of the gamma subunit of oligosaccharyl transferase in the Asian rice gall midge, Orseolia oryzae. Insect Mol Biol doi: 10.1111/j PubMed link
Sinha, D.K., Lakshmi, M., Anuradha, G., Rahman, S.J., Siddiq, E.A., Bentur, J.S., Nair, S. 2011. Serine proteases-like genes in the Asian rice gall midge show differential expression in compatible and incompatible interactions with rice. Int J Mol Sci 12, 2842-2852 PubMed link
Bhattacharjee, B., Mohan, M., Nair, S. 2010. Transformation of chickpea: effect of genotype, explant, Agrobacterium-strain and composition of culture medium. Biol Plant 54, 21-32
Rawat, N., Sinha, D.K., Rajendrakumar, P., Shrivastava, P., Neeraja, C.N., Sundaram, R.M., Nair, S., Bentur, J.S. 2010. Role of pathogenesis-related genes in the rice-gall midge interactions. Curr Sci 99, 1361-1368
Reddy, R.A., Kumar, B., Reddy, P.S., Mishra, R.N., Mahanty, S., Kaul, T., Nair, S., Sopory, S.K., Reddy, M.K. 2009. Molecular cloning and characterization of genes encoding Pennisetum glaucum ascorbate peroxidase and heat-shock factor: Interlinking oxidative and heat-stress responses. J Plant Physiol 166, 1646-1659 PubMed link
Reddy, P.S., Mahanty, S., Kaul, T., Nair, S., Sopory, S.K., Reddy, M.K. 2008. A high-throughput genome-walking method and its use for cloning unknown flanking sequences. Anal Biochem 381, 248-253 PubMed link
