Covalent Immobilization of Microtubules on Glass Surfaces for Molecular Motor Force Measurements and Other Single-Molecule Assays

We present an MT-surface coupling protocol in which aminosilanized glass is formylated using the cross-linker glutaraldehyde, fluorescence-labeled MTs are covalently attached, and the surface is passivated with highly pure beta-casein. The technique presented here yields rigid MT immobilization while simultaneously blocking the remaining glass surface against nonspecific binding by polystyrene optical trapping microspheres. This surface chemistry is straightforward and relatively cheap and uses a minimum of specialized equipment or hazardous reagents. These methods provide a foundation for a variety of optical tweezers experiments with MT-associated molecular motors and may also be useful in other assays requiring surface-immobilized proteins.
Source: Springer protocols feed by Cell Biology - Category: Cytology Source Type: news