(A) design of antibody-based scaffolding system for structure analysis of small-sized proteins in EM

Abstract

Analyzing the 3D structure of a protein is fundamental in understanding the function of the protein and its interaction with other biomolecules. Recently, protein structure analysis using the cryo-EM has become prevalent among structural biologists due to the rapid advances in microscopes, detectors and the computer software that process the data. However, elucidating the 3D structure of a small-sized protein is still a challenge. There have been many different approaches to solve this problem. One of the solutions is to develop a scaffolding system that is relatively bigger in size than the target protein. By linking the small-sized target protein to the relatively bigger scaffolding system, imaging is expected to become considerably easier. In this research, we designed and tested a novel scaffolding system based on antibodies. Antibodies are connected to other proteins of renowned protein interactions to create a new protein complex. By changing the types of antibodies of the scaffolding system, we hope to develop a universal scaffolding system appropriate for analyzing 3D structures of various small-sized proteins.