Precise and Reversible Protein-Microtubule-Like Structure with Helicity Driven by Dual Supramolecular Interactions

Area of Science:

• Biomaterials Science
• Supramolecular Chemistry
• Structural Biology

Background:

• Protein microtubules are vital natural structures with complex biological roles.
• Replicating their precise structure and controllable self-assembly is a significant scientific challenge.
• Existing methods often require chemical or biological modification of proteins.

Purpose of the Study:

• To develop a method for creating homogeneous protein microtubules without altering the protein.
• To elucidate the precise structure and self-assembly mechanism of these novel protein microtubules.
• To explore the potential biological applications of the engineered protein microtubules.

Main Methods:

• Utilized dual supramolecular interactions: protein-sugar interactions and π-π stacking.
• Employed tetrameric soybean agglutinin as the protein building block.
• Combined cryo-electron microscopy (cryo-EM) single-particle reconstruction and computational modeling.

Main Results:

• Achieved highly homogeneous protein microtubules through designed ligands.
• Determined the helical structure composed of three protofilaments, each with soybean agglutinin tetramers.
• Observed structural and dynamic resemblance to natural microtubules, including controllable and reversible assembly.
• Demonstrated the protein microtubules' capacity to enhance immune response.

Conclusions:

• Successfully engineered protein microtubules with high homogeneity and biomimetic properties.
• The study provides a novel strategy for designing self-assembled protein architectures.
• The developed protein microtubules hold significant promise for diverse biological applications, particularly in immunology.