Finalist EPFL doctorate Award 2010 - Dorsaz Nicolas
© 2010 EPFL
Dorsaz Nicolas' scientific work is (according to the opinion of the jury) ranking among the best 3 % PhD theses awarded by EPFL in 2009. Thesis EPFL, no 4375 (2009). Dirs.: Prof. Alfonso Baldereschi and Prof. Giuseppe Foffi.
A colloidal approach to eye lens protein mixtures : relevance for cataract formation.
Cataract is one of the leading cause of blindness. This loss of transparency of the eye lens originates from the alteration of the spatial distribution of the lens crystallin proteins. In this thesis, we developed a coarse-grained model for binary mixtures of alpha and gamma crystallin proteins.
We demonstrated that transparency of the eye lens is greatly enhanced by a weak, short-range attraction between alpha and gamma crystallin, which considerably decreases the critical temperature and the corresponding opacity due to light scattering. The phase diagram of the binary model mixture was found to depend on the alpha-gamma attraction in a manner that is both extremely sensitive and nonmonotonic.
More generally, we have shown that phase transitions and the related large fluctuations of the protein composition can play an important role in the eye lens opacification process.