Altered tubulin assembly dynamics with N-homocysteinylated human 4R/1N tau in vitro

► We modified tau by N-homocysteinylation (0.15, 1.5 and 15 mM). ► We found that 25 Lys residues are particularly susceptible to modification in the presence of 15 mM tHcy. ► Binding of tau to MTP is inhibited upon modification, depending on the degree of N-homocysteinylation. ► N-Hcy-tau species, compared to unmodified tau, change the assembly parameters, critical concentration and morphology of MTP.