Modulating mechanical stability of heterodimerization between engineered orthogonal helical domains

Nat Commun. 2020 Sep 8;11(1):4476. doi: 10.1038/s41467-020-18323-w.

Abstract

Mechanically stable specific heterodimerization between small protein domains have a wide scope of applications, from using as a molecular anchorage in single-molecule force spectroscopy studies of protein mechanics, to serving as force-bearing protein linker for modulation of mechanotransduction of cells, and potentially acting as a molecular crosslinker for functional materials. Here, we explore the possibility to develop heterodimerization system with a range of mechanical stability from a set of recently engineered helix-heterotetramers whose mechanical properties have yet to be characterized. We demonstrate this possibility using two randomly chosen helix-heterotetramers, showing that their mechanical properties can be modulated by changing the stretching geometry and the number of interacting helices. These helix-heterotetramers and their derivatives are sufficiently stable over physiological temperature range. Using it as mechanically stable anchorage, we demonstrate the applications in single-molecule manipulation studies of the temperature dependent unfolding and refolding of a titin immunoglobulin domain and α-actinin spectrin repeats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinin / chemistry
  • Biomechanical Phenomena
  • Connectin / chemistry
  • Models, Molecular
  • Molecular Dynamics Simulation
  • Protein Conformation, alpha-Helical
  • Protein Domains
  • Protein Engineering*
  • Protein Folding
  • Protein Multimerization*
  • Protein Stability*
  • Protein Structure, Quaternary
  • Protein Unfolding
  • Single Molecule Imaging
  • Temperature

Substances

  • Connectin
  • Actinin