We work on environmental contamination caused by extensive use of persistent pesticides like hexachlorocyclohexane (HCH) and other organochlorine compounds. We have attempted bioremediation of HCH contaminated agricultural sites by ‘bioaugmentation’ and ‘biostimulation’ with encouraging results. Currently we are exploring the potential of ‘enzymatic bioremediation’ by deploying enzymes involved in degradation of HCH for clean-up of such sites, and have completed the genome of a bacterium that produces rifamycin.
We focus on purification and characterization of a novel SWI/SNF family of ATP-dependent chromatin remodeler from chicken liver. We have found a novel H3-specific protease that specifically cleaves N-terminal portion of histone H3, thereby removes epigenetic marks on it. We have established a model of liver regeneration in mouse, to study epigenetic regulation of regeneration process. Using an inflammatory model system in mouse, we study changes in oscillatory response of the key inflammatory transcription factor, NF-B.
Our research is focused on comparative immuno-endocrinology and reproductive physiology, using both in-vivo and in-vitro approaches. We also investigate cell-cell interactions in the testis, Leydig cell activities by Sertoli cells, mast cells and testicular macrophages. In ectotherm vertebrates, we are working on endocrine and paracrine regulation of testicular immune responses. We also work fish: immunoregulatory role of hypothalamo-hypophsial-adrenocortical axis, symathoadrenomedullary system, pineal gland and endogenous opioid peptides.
We work on nutritional physiology of carp larvae. We evaluate digestive enzyme profiles in carps during ontogenic development, and carry out purification and characterization of proteases (trypsin and chymotrypsin) in digestive system of Indian major carps. Our research interests extends to the development of aquaculture techniques for fish and fish feed, e.g. zooplankton, and the role of zooplankton in larviculture. We have designed an eco-friendly recirculating system using a combination of biological filter and hydroponic system.
Our studies have established that estrogens regulate the synthesis of vitellogenin and choriogenin in the liver. We have (i) shown the expression of Vg (A and B) and ER (α and β) genes in response to estrogenic compounds, (ii) developed specific and highly sensitive ELISA for detection of vitellogenin and choriogenin in fish blood, and (iii) standardized techniques for isolation of viable hepatocytes, and used them in in-vitro investigation of metabolism and biosynthetic activities in liver cells. Our current focus is on the mechanism of egg hardening, that is essential for successful embryogenesis and hatching of viable young fishes.
Our research centers on understanding the mechanisms by which daily clocks and yearly calendars control temporal organization of behaviours, physiology and life history in song birds. We focus on: (i) to demonstrate the involvement of biological clocks in pre-migratory and migratory behaviours, (ii) changes in the brain (neurogenesis/ synaptogenesis) in response to seasons and life history stage, (iii) endocrinology of seasonal behaviours, and (iv) gene and protein expression in relation to changes in the life history status.
We are involved in developing an environmentally safe biorational pest management strategy using nuclear techniques in radio-genetic methods and augmentation of biological control, with continuous support of IAEA. ‘Inherited Sterility Technique’ (a modified SIT) using sub-sterilizing gamma doses is established for the suppression of a serious tropical pest, Spodopteralitura. Studies on use of radiation as phyto-sanitary treatment, radiation biology of mosquitoes and Sf9 (a highly radio-resistant insect cell line) as a eukaryoticmodel, and radiation hormesis are in progress.
My laboratory works on pesticide residue analysis and microbial biodiversity and ecology of soil from different regions and condition. We focus on isolation and identification of unexplored free living nitrogen fixing bacteria, and have isolated nif H gene from unculturable bacteria, a nitrogen metabolizing bacteria with role in nitrogen fixation. We also work on endosulfan degradation, and have isolated microbes Bordetella sp. B9, Pseudomonas aeruginosa S9 and Pseudomonas aeruginosa S2, which can quickly degrade endosulfan.
Our current research focus is on the identification of disease susceptibility genes in granulosa cells of human PCOS patients with and without Insulin resistance”. We also look into the “signaling mechanism involved in the regulation of glucose metabaolism in granulosa cells by FSH and LH”. Another major area we focus on is “Proteomics of human Plasma from Lung, Breast and Ovarian cancer Patients for discovering Cancer Biomarkers.
We are trying to understand the pathogenicity of A. hydrophila using both fish and mouse model. We have identified the role of virulence plasmid in the pathogenicity and suggested mechanisms by which the bacterium induces host cell apoptosis. We also work on the mechanisms of arsenic toxicity and are currently engaged in studying the signal transduction pathways induced by arsenic with aim of using this information to induce apoptosis of cancer cell, especially of chemo-resistant variety.
We have three major research interests. (i) To understand the biology of macrophages and dendritic cells (DCs) under stress conditions, and the regulatory mechanisms in signal transduction during interaction of macrophages/DC cells with other cells of the immune system. (ii) To assess the regulation of signaling mechanism involved in tumorigenesis and tumor progression. (iii) Nanomedicine: Developing nanoparticles as novel carrier and adjuvant for DNA Vaccine and for effective enzyme-prodrug therapy wherein the benign prodrug can be converted in functional drug at the targeted site.
My research is presently in the area of Molecular Genetics. We are studying the role of the oxidative stress inducible gene Hemeoxygenase 1 (Hmox1) in development. We are analysing the expression of this gene during normal mouse development and studying the consequences of its mutation in the gene-targeted mouse. Our results show that mutation of this gene does not cause marked developmental abnormalities. We are also studying the molecular phylogeny of the heme degradation pathway.
We use insects as a model to understand the role of gut microbial community in their hosts. Using Helicoverpaarmigera and Bemisiatabaci, we aim to study the gut microbial structure and the functional role played by these microbes in the insect’s growth and development. We propose that understanding the microbial diversity in insect guts and their critical roles in insect growth and development will offer crucial information for designing future pest management strategies.
Our laboratory aims to understand the dynamics of life-history trait associations in Drosophila melanogaster through simultaneous selection on two traits that are shown to be negatively genetically correlated. There has been positive selection response for the two divergent traits, for more than 100 generations now. Through comparative studies of these selected and their unselected ancestral populations, we aim to provide a better understanding to the fine print associated with evolution of life-history traits using various experimental approaches.
We aim to understand the mechanisms of late onset neurodegeneration in human with particular focus on the polyglutamine diseases including Huntington’s Disease. We have humanized flies (Drosophila) by inserting mutant human disease genes such as the Huntington’s gene into flies. Using the transgenic fly model, which mimics the disease symptoms, we are trying to understand the mechanisms of neurodegeneration and also identify therapeutic strategies with least side effect for the treatment of these devastating disease.
Thrust areas: Cancer Epidemiology, Cancer Cell Signaling and Identification of Novel Targets for Drug Development. Epidemiological studies are being performed to unveil the novel biological markers for early and easy identification of various cancers. Investigations on cancer cell signaling are being performed to understand the molecular signaling that contributes to carcinogenesis. We are also trying to identify novel molecular targets for anti-cancer drug development. We also plan to identify and test the natural compounds to ascertain their anti-cancer properties for their commercial exploitation.