Mechanical regulation of integrin conformation
Abstract
The scientific objective of this research is to elucidate biophysical mechanism underlying the mechanical regulation of ligand binding and conformational change of av§3 integrin using specific mutations to manipulate its molecular structure and single-molecule force spectroscopy. The research effort will be a collaboration between the Schwartz group at Yale Medical School (a member of the ARO Force-Activated Synthetic Biology MURI team) and Cheng Zhu s group at Georgia Tech. Integrin is a nanoscale biological mechano-sensor and Ðtransducer. Integrin-mediated mechanotransduction in cells is hypothesized to relate to ligand binding and conformational change of integrins: conformationally extended-activated integrin has higher affinity for its ligand. Therefore, the Schwartz group will produce a panel of known point mutations that stabilize the extended-activated conformation of integrin av§3. The wild-type (WT) and mutant integrin proteins will then be investigated in the Zhu lab using a biomembrane force probe. Using single-molecule constant-force spectroscopy, the Zhu lab will quantify single integrinÐligand bond lifetimes at forces ranging from 0-40 pN. Molecular stiffness measurements will also be used to assess integrin conformation, whether bent or extended. The experiments will analyze WT and three mutants in the §3 subunit that favor the extended-activated conformation (D723R, L138I and S243E). Double mutations that combine D723R with other extracellular domain mutants to give stronger conformational activation effects may also be included. The result will help to further understand the role of force in regulation of integrin conformation and downstream signaling. Also, this study will provide insight to develop new biological protein materials with force-dependent responses.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2017
- Source ID
- W911NF1610257
Entities
People
- Cheng Zhu
Organizations
- Army Contracting Command
- Georgia Tech Research Corporation
- United States Army