Expression of Mono- and Dimeric Ganglioside-Binding Lectins and Their Cellular Functions

In the 2020s, a novel R-type lectin family with β-trefoil folding was found in Mytilidae (phylum Mollusca). SeviL, as described in this chapter, is the lectin discovered from Mytilisepta virgata, which is habituated in the intertidal community in the northwestern Pacific Ocean. SeviL is bound to the glycan moiety of gangliosides such as asialo-GM1 (GA1: Galβ1-3GalNAcβ1-4Galβ1-4Glc), GM1b (Neu5Acα2-3Galβ1-3GalNAcβ1-4Galβ1-4Glc), and SSEA-4 (Galβ1-3GalNAcβ1-3Galα1-4Galβ1-4Glcβ1), leading to apoptosis of cancer cells and M1 macrophage polarization. We describe how to prepare dimeric and monomeric SeviLs, which are valuable in studying the function of gangliosides in terms of glycan recognition. It also introduces how to apply lectins to ganglioside studies on concentration-dependent growth inhibition and cell differentiation.