University of California, Santa Barbara

Valentine Biomechanics Lab: What determines cell strength?

High-resolution microscopy of cytoskeletal networks

Cells contain a dense polymer network called the cytoskeleton that provides shape and strength and allows them to crawl and divide. Unlike macroscopic engineering structures, the cytoskeleton is dynamic and enzymatically active, and therefore able to respond to chemical and mechanical inputs in real time.

We seek to understand the molecular origins of strength in the cytoskeleton using novel microscopy and micromanipulation techniques. Our results will not only advance our understanding of stem cell differentiation, wound healing, and other force-sensitive biological processes, but will allow improved treatments and diagnostics for diseases including Alzheimer’s and cancer. More generally, our experiments will provide new insight into the physics of self-assembled systems and will enable the development of novel bio-inspired materials.

In this experiment, small magnetic beads are embedded in a purified cytoskeletal network, and ‘magnetic tweezers,’ are used to apply controlled forces. By correlating network deformation, architecture, and composition, we will establish the molecular origins of elasticity and strength.

This project is performed in collaboration with the Saleh Research Group (Materials), and funded by the UCSB-Santa Barbara Cottage Hospital Special Research Award for  Biomedical Science and a Career Award at the Scientific Interface from the Burroughs Wellcome Fund. 



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