Molecular Models of Human Elastin and Elastin Biomaterials

Abstract

The elastin polymer, assembled from its molecular precursor tropoelastin, is the dominant component of elastic fibers, which confer elasticity and structural integrity to skin, lung, connective and vascular tissue. Historically, elastin's dynamic nature has precluded traditional approaches such as X-ray crystallography to understand its detailed features. Here, I describe recent work using atomistic and coarse-grained models for predicting elastin's molecular structure, mechanical properties and mechanisms, as well as dynamics. We use the models to probe the function of key molecular regions, investigate disease etiology and explore implications for hierarchical assembly. From the materials perspective, elastin-based materials display tunable thermal sensitivity, presenting opportunities to mimic and control these responsive features for biomedical applications. We characterize the temperature response spectrum of elastin-like peptides to design synthetic polymers with tunable switching, resolving effects of peptide chemistry, chain length, and solvent environment. We also study a chimera silk-elastin-like protein polymer that combines silk's strength with elastin's extensibility and responsive features to identify temperature transition effects on molecular-scale mechanics. We analyze the associated free-energy landscape with the Bell-Evans model to interpret temperature-induced phase transitions. Such a feedback loop between simulation and experiment for predictive biomaterial design may enable new applications in drug delivery and tissue engineering.