The use of Affimers to investigate the role of the SH2 domain in the MAPK pathway

Affimers are an antibody scaffold first developed in 2014 which are shown to have a high degree of specificity, reduced size (compared to antibodies) and good thermal stability, as well as being easy to produce. Previous work has generated a variety of Affimers which block protein-protein interactions essential to cell signalling. One of these pathways is the MAPK pathway which primarily controls cell proliferation. This pathway is of particular interest due to the prevalence of its overactivation in tumour cells causing constitutive cell division. In this project Affimers were used to inhibit the protein-protein interactions of SH2 domain containing proteins to determine if they had previously unknown activity within the MAPK pathway. This study was unsuccessful in identifying any such proteins. Progress was made towards developing an assay that can assess the effect of Affimers on the MAPK pathway. In addition to this crystals were obtained of an Affimer-SH2 complex, however when diffracted they did not produce high resolution data. Further knowledge of the MAPK pathway, how it is activated and how it uses protein-protein interactions to affect the cellular environment could lead to better treatments and patient outcomes.