MERS-CoV Spike S2 Protein

MERS-CoV is a coronavirus which causes the Middles East Respiratory Syndrome (MERS). MERS-CoV has four structural proteins, known as the S (spike), E (envelope), M (membrane), and N (nucleocapsid) proteins. The spike protein is responsible for allowing the virus to attach and fuse with the membrane of a host cell. Spike glycoprotein is cleaved into three chains: S1, S2’ and S2. S1 mainly contains a receptor binding domain (RBD), which is responsible for recognizing the cell surface receptor. S2 contains basic elements needed for membrane fusion. MERS-CoV S mediates viral attachment and fusion to human cells via human cellular receptor DPP4, also known as CD26. The S protein plays an important role in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity.