Figure 3.

Protein–protein interaction seems to be an important element that determines protein function. (A) Normal function as a competing pathway to aggregation. (B) Schematic representation of the role of phosphorylation of S776 as a molecular switch. When S776 is non-phosphorylated, ataxin-1 (Atx1) is part of a large multiprotein complex and is likely to engage in multiple cooperative interactions with spliceosomal factors being thus protected against aggregation. When it is phosphorylated, it interacts with 14-3-3 and other such proteins and remains more prone to aggregation.