Generating Novel Materials Using the Intrinsically Disordered Protein Ubx

The development of functionalized materials is needed to enable diverse applications. Protein-based materials are typically biocompatible and biodegradable and can exhibit a wide variety of useful mechanical properties. Most importantly, gene fusion enables facile incorporation of active proteins into the materials. However, many protocols rely on denaturing conditions to stimulate materials formation. These conditions would be expected to inactivate any appended functional proteins. This chapter describes methods to create protein fibers and films in a mild aqueous buffer near neutral pH. This facile, inexpensive single-pot approach to materials assembly does not require any special equipment. Also included in this chapter are methods to fuse fibers to form fiber bundles, and to use fibers for cell culture. Although these methods were developed to generate materials from the Drosophila Hox transcription factor Ultrabithorax, they may also work for other self-assembling proteins, many of which have sequence features in common with Ubx.