Cellular immunity depends on major histocompatibility complex class I (MHC I). The transporter associated with antigen presenting (TAP) translocate peptides from the cytoplasm into the ER lumen, where they are presented to the MHC I molecules. Although the function of TAP is known, at structural level the conformation of TAP is still unknown.
The aim of my study is to understand the conformational changes that the TAP complex undergoes during peptide transport. The complex will be trapped in different conformations and immunoprecipitated while keeping the native interaction with the lipid bilayer. The conformation will be further studied with electron microscopy.