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Research Interests: 

My research interests are centered on the structure, function and biogenesis of multi-subunit enzymatic complexes present in the membranes of chloroplasts and mitochondria and their pivotal role in growth, development and survival of organisms.  Presently, I am pursuing research and supervising research in a project aimed to elucidate regulatory pathways that control protein synthesis and targeting of chloroplast encoded integral membrane proteins in Arabidopsis thaliana, using biochemical, reverse genetics and genetic approaches. 

In past, I studied translational control mechanisms in mitochondria, with specific focus on the biogenesis of the cytochrome c oxidase complex (located in the inner Mitochondrial membrane) using S. cerevisiae, the only eukaryote capable of surviving in absence of functional mitochondria.  The core of the cytochrome c oxidase is composed of three mitochondrially-coded subunits Cox1p, Cox2p and Cox3p, which are inserted into the inner membrane from the inside.  Translation of the COX1, COX2, and COX3 mRNAs is activated by the nuclear-coded proteins Pet309p, Pet111p, and the concerted action of Pet54p, Pet122p and Pet494p respectively.   My work showed that COX1, COX2 and COX3 m-RNA specific translational activators bound to inner mitochondrial membrane interact physically among themselves suggesting co-localized synthesis of Cox1p, Cox2p and Cox3p on inner membrane in a way that facilitates assembly of the core complex.  In addition, protein-protein interaction data suggested involvement of Nam1p in organized delivery of nascent mt-mRNAs from matrix to the membrane localized translation system.

I also used unicellular cyanobacterium Synecocyctis PCC 6803 to study function of small subunits PsaK and PsaM associated with Photosystem I and to elucidate biosynthetic pathway of Phylloquinone, an electron transfer co-factor in photosystem I & studied gene organization and expression profile of photosystem genes in a tree sp. poplar under varying seasonal, developmental and diurnal condition.  Additionally, I share an interest in plastid gene evolution.