Meeting Abstract

S7.2  Tuesday, Jan. 6  From Soft Cells to Hard Keratins – The Many Lives of Intermediate Filaments FUDGE, D.S.*; BERIAULT, D.; SZEWCIW, L.; MCCUAIG, J.; RUSSELL, D.; LANE, E.B.; VOGL, A.W.; University of Guelph; University of Guelph; University of Guelph; University of Guelph; University of Dundee; University of Dundee; University of British Columbia dfudge@uoguelph.ca

Intermediate filaments (IFs) are a diverse group of 10 nm cytoskeletal filaments that occur in most animal cells and impart mechanical integrity to the cells and nuclei in which they are found. They are especially abundant in epithelial cells, and they make up the fibrous fraction of the non-living materials known as alpha-keratins that occur in amniotes. Recent work on IF mechanics has overturned the notion that IFs in cells have the same mechanical properties as IFs in hard alpha-keratins such as wool. These studies have demonstrated that IFs as they occur in living cells are far more compliant and extensible than IFs in alpha-keratins. In this talk I will discuss the range of mechanical properties exhibited by IF-reinforced materials and the ways that they are suited to their use in life. Using a variety of illustrative examples, I will also discuss some of the mechanisms whereby the mechanical properties of IFs can be modified for particular mechanical functions. Examples will include work we have done on the biomechanics of human keratinocytes, hagfish slime, wool, and whale baleen. At the end of the talk I will provide some insights into the evolution of IF-based materials and the roles they may have played in the history of life on Earth.