Single molecule study of heterotypic interactions between mucins possessing the Tn cancer antigen

摘要: Mucins are linear, heavily O-glycosylated proteins with physiological roles that include cell signaling, adhesion, inflammation, immune response and tumorgenesis. Cancer-associated mucins often differ from normal by presenting truncated carbohydrate chains. Characterization of the binding properties side chains could thus prove relevant for understanding their role in cancer mechanisms such as metastasis recognition system. In this work, heterotypic interactions model possess Tn (GalNAcαThr/Ser) T (Galβ1-3GalNAcαThr/Ser) antigens derived porcine submaxillary mucin (PSM) were studied using atomic force microscopy. PSM possessing only antigen (Tn-PSM) was found to bind analogs a combination T, STn well biosynthetic core 1 blood group A tetrasaccharide (GalNAcα1-3[Fucα1-2] Galβ1-3GalNAcαSer/Thr). The rupture forces ranged 18- 31 pN at force-loading rate ∼0.5 nN/s. thermally averaged distance bound complex transition state (xβ) estimated be range 0.37-0.87 nm first barrier Bell Evans analysis within 0.34-0.64 based on lifetime analysis. These findings reveal strength energy landscape Tn-PSM above mucins, resemble homotypic Tn-PSM. This suggests common epitope analogs, finding may important cells.