Interaction of Plasmodium yoelii tryptophan-rich antigen 7 with CD71 on macrophage membrane regulates host inflammatory response

To screen for candidate interacting proteins of PyTRAg7 protein and macrophage membrane proteins, differential bands were identified by immunoprecipitation combined with silver staining and mass spectrometry. Excised protein bands were destained, reduced, allylated, and digested with trypsin for 20h at 37°C. Eluted peptides were analyzed using the Q-Exactive mass spectrometer (Thermo Scientific) for 60 min. The mass spectrometer was operated in positive ion mode. Full scan MS spectra (m/z 300–1800) were acquired with a resolution of 70000 at 100 m/z. Automatic gain control (AGC) target was set to 1e6; Maximum inject time was 50 ms, and dynamic exclusion was 30.0s. Up to 20 most intense ions were selected for higher-energy collisional dissociation fragmentation depending on signal intensity. Isolation window was 1.5 m/z; MS/MS fragment spectra were acquired with a resolution of 17500 at 100 m/z, AGC target was 1e5; Maximum inject time was 50 ms; Normalized collision energy was 27eV, and underfill was 0.1%. MS raw data was analyzed with Proteome Discoverer Daemon 2.5.