Selective placement of actin filaments on protein patterned surfaces

Motors proteins are used by living organisms to convert chemical energy into mechanical energy. The human body uses such motors proteins to transport materials through cells and, in the case of the biomolecular motor system of actin and myosin, to contract muscle. By understanding how these biological motors work, artificial motors with improved function may be possible and may be engineered to work in complex biological and non-biological environments. Recent research efforts have focused on understanding how to harness the power of, and manipulate the functioning of biological motors for integration into useful nanoscale systems. One important step towards this integration is the binding of motor proteins onto substrates and the full characterization of the system. The aim of this thesis was to study the feasibility of selective immobilization of actin filament motor protein based on the bioaffinity reaction between patterned streptavidin on a substrate and biotinylated actin filaments on an aminopropyltriethoxysilane (APTES)-functionalized glass surface. Gelsolin was used to cap the barbed/positive end of actin and to link actin to biotin molecules on the functionalized surface. Results demonstrate significant binding of actin filaments on streptavidin patterned surfaces via bioaffinity immobilization. Fluorescent microscopy and image processing software were used to characterize these results. Characterization of the APTES-functionalized surface was conducted using atomic force microscopy (AFM). The relationship between actin and gelsolin capping protein was examined as well as non-specific binding control of actin filaments.