ABSTRACT
Snake venoms contain two types of C-type lectins based on structural features and functional properties: snake C-type lectin-like proteins (snaclecs) and sugar-binding snake lectins. There is some sequence homology between these two protein classes. Most snake lectins are 26–28 kDa homodimers that agglutinate erythrocytes only via binding to carbohydrates. On the other hand, snaclecs are homologous heterodimers forming monomers or oligomers (αβ)x and contribute to the disruption of hemostasis in envenomed prey by activating or inhibiting a wide range of plasma components or blood cell types (especially platelets). Snaclecs, with a relatively conservative and homologous structure (primary, secondary and tertiary), are unique in their diverse biological targets and have become useful tools in studies of protein structural and functional relationships. The thorough characterization of the snaclec convulxin contributed greatly to the cloning and identification of glycoprotein (GP) VI and helped to open the field of platelet signaling transduction pathways via GPVI. Botrocetin, a von Willebrand Factor modulator, has been broadly applied in clinical diagnostics. In this chapter, I report recent findings on snaclecs and snake sugar-binding lectins as well as their targets and interacting mechanisms.
