Purpose of proposed research..To investigate the structure of complexs between nectins and its ligand..To determine how nectins interact with viral ligands ,this may be a crucial step for viral entry and spreading from cell to cell..To define how the cell responds when nectin engages cellular versus viral ligands...Proposed Plan..The study will be focus on the nectins, family of cell adhesion molecules of the visus (influenza virus or streptococcus suis) involving host-virus protein-protein interaction and protein conformational changes. ..Expected results and impacts..An understanding of how the virus get into the host cells and any events that may happen in this process either host-virus protein-protein interaction or protein conformational changes. In addition, the understanding could provide a basic knowledge for a better way for dealing with the virus.