Comparative Protein Profiling of Hypoxia Susceptible and Tolerant Rats

Abstract

Low availability of oxygen at higher altitudes has a great impact on the life processes newlineof tourists, mountaineers, soldiers and other population residing in these regions. The newlinecellular level of molecular oxygen affects expression and activity of cellular newlineproteins, which in turn are controlled by various pathways. There is a widespread newlineneed and interest to find out protein(s) that are possibly involved in imparting newlinehypobaric hypoxia tolerance to individuals. In the present study, male albino Sprague newlineDawley rats were segregated into susceptible, tolerant and normal groups depending newlineon their gasping time when exposed to simulated hypobaric hypoxia of 32,000 ft newline(9,754 m). Comparative proteome profiling of blood plasma and lung protein of newlinehypoxia susceptible, tolerant and normal group of rats was done using 2-D gel newlineelectrophoresis. newlineThree proteins with more than 4 fold higher expression levels in blood plasma were newlineselected separately from tolerant and susceptible samples. Characterization of these newlineproteins from tolerant sample using MALDI-TOF/TOF and MASCOT search newlineindicated their homology with two different super-families viz NADB-Rossmann newlinesuperfamily (Rab GDP dissociation inhibitor and#946;) and Transferrin superfamily (two newlineSerotransferrins). Three high level up-regulated proteins characterized from the blood newlineplasma of hypoxia susceptible rats indicated their similarity with threonine tRNA newlineligase (mitochondrial), carbohydrate sulfotransferase 7 and aspartate tRNA ligase newline(cytoplasmic) that are known to play a role in ATP binding, carbohydrate metabolism newlineand protein biosynthesis, respectively. newlineIn-silico studies of these upregulated plasma proteins in tolerant rats (Serotransferrin newlineand Rab GDP dissociation inhibitor and#946;) were done using homology modeling. 3D newlinestructures of these proteins were modeled and their interactions with other proteins were studied. Serotransferrin is a 698 amino acid long protein in Rattus norvegicus. newlineStructure predicted had an instability index of 34.15 which establishes it to be appreciablly stable.