Chattopadhyay, TirtharthaKUMAR, Pawan2017-02-172017-02-172016-06http://krishikosh.egranth.ac.in/handle/1/5810001383Germin-like proteins are plant glycoproteins-familybelonging. Theyare to structurally similar but functionally diverse, and have been found to be involved in resistance of plants against several biotic and abiotic factors. Though characterized in different crop plants, detailed characterization of germin-like proteins in the important vegetable crop tomato has remained unexplored. In this study, a gene (SlGLPH) encoding a germin-like protein belonging to GER 2 sub-family of tomato has been characterized. Different physico-chemical properties of the SlGLPH protein was analysed in silico. The SlGLPH protein was found to share sequence similarity with plant auxin binding proteins with a predicted sub-cellular location at plant cell wall, indicating its possible involvement in auxin signalling in tomato plants. Structural model of the SlGLPH protein revealed characteristic-jellyrollstructurewithconservedβactive site architecture for metal ion (Mn2+) binding. Through semi-quantitative reverse transcriptase (RT)-polymerase chain reaction (PCR), the relative abundance of the SlGLPH transcript was found to be increased under abiotic stress conditions (salt, heat, and cold), indicating the stress-responsiveness of the gene. Conditions for recombinant SlGLPH protein expression [coded by either by the last 573 base pair (bp) partial coding DNA sequence or by the last 384 bp partial coding DNA sequence of the SlGLPH gene] in bacterial system were optimized, where the recombinant SlGLPH protein was observed to be solubilized in presence of low concentration (0.5 %, w/v) of ionic detergent (SDS) only. Hence, strategies were optimized for purification of the recombinant SlGLPH protein through immobilized metal affinity chromatography in presence of the ionic detergent (SDS). Through optimized purification strategy, purified recombinant SlGLPH protein was obtained at high yield and purity. This purified protein is suitable for use as antigen in order to raise polyclonal antibody against the SlGLPH protein, which will be indispensable for expression analysis of the SlGLPH gene at protein level. Thus, the present study paves the way for further detailed functional characterization of the SlGLPH protein in near future.en---Thesis