The present study was initiated to elucidate the role of lipid rafts in lung surfactant secretion. Lipid rafts were isolated and probed for the association of SNARE proteins. Cholesterol depletion was done to study its role in modulating the surfactant secretion and membrane fusion. Flotillin proteins were silenced to examine their role in surfactant secretion. Finally, we determined the proteomic profile of type II cell lipid rafts to identify novel proteins in this unique subproteome and study the roles of one of the identified proteins, namely, v-ATPases, in surfactant secretion. We have used a number of techniques including RT-PCR, immunoblotting, immunoflorescence, secretion assay, membrane fusion assay, isolation of plasma membrane and lamellar bodies, and RNA interference to address the biological phenomenon. 1. SNARE proteins were differentially associated with lipid rafts in a cholesterol-dependent manner. 2. Cholesterol depletion drastically reduced surfactant secretion, membrane fusion and fusion pVeterinary Pathobiolog
