Src homology domain 2 adaptors affect adherence of Salmonella enterica serovar Typhimurium to non-phagocytic cells

The ability of Salmonella enterica serovar Typhimurium (S. Typhimurium) to penetrate the intestinal epithelium is key to its pathogenesis. Bacterial invasion can be seen as a two-step process initially requiring adherence to the host cell surface followed by internalization into the host cell. Evidence suggests that adherence of S. Typhimurium to host cells is receptor-mediated; however, the host cell receptor(s) has/have not been identified. Internalization of S. Typhimurium absolutely requires the actin cytoskeleton yet only a few of the cytoskeletal components involved in this process have been identified. In order to identify host proteins that may play a role in S. Typhimurium invasion, the recruitment of actin-associated proteins was investigated. The contribution of recruited Src homology 2 adaptor proteins to invasion was further investigated and it was found that, while not involved in bacterial internalization itself, the adaptors Nck and ShcA influenced adherence of S. Typhimurium to non-phagocytic cells.