Echicetin itself inhibits aggregation of washed platelets induced by vWF, thrombin or alboaggregin-A (PubMed:8481512, PubMed:11290595). However, when complexed with the pentameric plasma immunoglobulin Mkappa (IgMkappa), echicetin binds specifically to GPIb and activates platelets. This is caused by P-selectin expression and activation of alpha-IIb/beta-3 as well as tyrosine phosphorylation of several signal transduction molecules, including p53/56(LYN), p64, p72(SYK), p70 to p90, and p120 (PubMed:11290595). In vivo, it induces thrombocytopenia when injected into mice (PubMed:8481512), probably accounting of activation of platelets rather than inhibition (PubMed:11290595). Heterodimer of subunits alpha and beta; disulfide-linked (PubMed:9163349). Forms an active complex with the pentameric immunoglobuline Mkappa (IgMkappa) (PubMed:11290595). Expressed by the venom gland. Belongs to the snaclec family. The name echicetin has been given to 2 different proteins, this one from E.carinatus sochureki and another one for which the subspecies has not been specified (E.carinatus). Most experiments have been done on E.carinatus sochureki.