(407b) Kinetics of Tau Protein Adsorption to a Model Hydrophobic Interface: The Role of Phosphorylation and Other Point Mutations

Abnormal aggregation of microtubule associating protein, tau, into neurofibrillar aggregates , due to protein mutations,  is a defining hallmark of several neurological diseases.  Recent research indicates that the polymerization of soluble tau proteins into paired helical filaments may be influenced by the hydrophobic properties of its monomers, the presence of inducers and the local environment. In this talk, we will discuss our recent results showing the similarities and differences in the adsorption and aggregation kinetics of tau proteins, in the presence and absence of mutations. In particular, we will discuss the role of hyperphosphorylation, as well as point mutations at the N and C terminus of the protein on the surface activity. We find that even though tau is a soluble protein, it is highly surface active at nanomolar concentrations. We also find that these proteins demonstrate a two-step adsorption to the hydrophobic interface, and that the adsorption kinetics is dependent both on the concentration and isoform of the protein. We will also discuss our surface rheological data which suggests surface induced aggregation in these proteins.