New Lectin Lsectin Interaction Between Protein And Gene Targeting Vector

Immunoreaction is based on self- and nonself-recognition, which function is exerted by the molecule called pattern recognition receptors(PRRs). C-type lectins, a novel PRRs family, play a important role in the recognition of microbes. Due to the fact that immune inhibiton signal was produced by some C-type lectins engaged with ligands, many pathogens including HIV, HCV taget them to escape from immunological surveillance. However, the intracellular signaling pathway engaged by C-type lectins remains less defined, and attracts great interesting. LSECtin (liver and lymph node sinusoidal endothelial C-type lectin), is a novel member of C-type lectin family originally identified in our lab, specially expressed in the liver and lymph node sinusoidal endothelial cells, and can associate with carbohydrate. However, its physiological function and intracellular signaling pathway remain unclear.In this study, through yeast two-hybrid screening in a human fetal liver cDNA library using the cytoplasmic fragment of LSECtin as the bait, four candidate interacting proteins were obtained and the interactions were proved in yeast. Based on combinational comparison of affinity force, functional association and subcellular localization, IFP35 (interferon-induced protein 35) and TRIP-1 (TGF-β type II receptor interacting protein-1) were selected for further demonstration in mammalian cells. Localization analysis showed that, LSECtin proteins overexpressed alone exhibited mainly uneven plasma membrane distribution and less punctate in the cytoplasm, whereas IFP35 exhibited punctate or diffused distribution in the cytoplasm, and TRIP-1 was localized both in the cytoplasm and on the plasma membrane. When co-expressed with LSECtin, either IFP35 or TRIP-1 was recruited to the region of highly expressing LSECtin and significant co-localization was observed. Moreover, co-immunoprecipitation assays in HEK-293T cells were performed...