Study of mechanism of huntingtin aggregation by monitoring the pathological toxic intermediates (like dimers, tetramers and soluble oligomers) formed on pathway using single molecule fluorescence technique Fluorescence correlation spectroscopy (FCS). Studied aggregation kinetics of full length huntingtin exon1 using HPLC based sedimentation assay (RP- HPLC and SEC), and dynamic light scattering (DLS) methods. Investigated the conformational dynamics of N-terminal region in huntingtin using fluorescence resonance energy transfer (FRET) and FTIR.