A GM1b/asialo‐GM1 oligosaccharide‐binding R‐type lectin from purplish bifurcate mussels Mytilisepta virgata and its effect on MAP kinases

• Published in: The FEBS journal Vol. 287; no. 12; pp. 2612 - 2630
• Main Authors: Fujii, Yuki, Gerdol, Marco, Kawsar, Sarkar M. A., Hasan, Imtiaj, Spazzali, Francesca, Yoshida, Tatsusada, Ogawa, Yukiko, Rajia, Sultana, Kamata, Kenichi, Koide, Yasuhiro, Sugawara, Shigeki, Hosono, Masahiro, Tame, Jeremy R. H., Fujita, Hideaki, Pallavicini, Alberto, Ozeki, Yasuhiro
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01-06-2020; John Wiley and Sons Inc
• Subjects: Amino acid sequence; Amino acids; Animals; Antibodies; Apoptosis; Bifurcations; Binding; Binding Sites; bivalves; Breast cancer; Cancer; Caspase; Cell surface; Cytotoxicity; Dimers; G(M1) Ganglioside - analogs & derivatives; G(M1) Ganglioside - chemistry; G(M1) Ganglioside - metabolism; ganglioside; Gills; Glycan; HeLa Cells; Humans; Kinases; Lectins; Lectins - chemistry; Lectins - isolation & purification; Lectins - metabolism; Mantle; MAP kinase; Mass spectrometry; Mass spectroscopy; Mitogen-Activated Protein Kinases - chemistry; Mitogen-Activated Protein Kinases - metabolism; MKK3 protein; Mollusks; Mussels; Mytilidae - chemistry; Mytilidae - metabolism; Mytilisepta virgata; Nucleotide sequence; Nucleotides; Oligosaccharides; Oligosaccharides - chemistry; Oligosaccharides - metabolism; Original; Ovarian cancer; purplish bifurcate mussels; R‐type lectin; Sequences; Species Specificity; Time dependence; R-type lectin; purplish bifurcate mussels; Mytilisepta virgata; bivalves; ganglioside
• ISSN: 1742-464X; 1742-4658
• DOI: 10.1111/febs.15154

A 15‐kDa lectin, termed SeviL, was isolated from Mytilisepta virgata (purplish bifurcate mussel). SeviL forms a noncovalent dimer that binds strongly to ganglio‐series GM1b oligosaccharide (Neu5Acɑ2‐3Galβ1‐3GalNAcβ1‐4Galβ1‐4Glc) and its precursor, asialo‐GM1 (Galβ1‐3GalNAcβ1‐4Galβ1‐4Glc). SeviL also interacts weakly with the glycan moiety of SSEA‐4 hexaose (Neu5Acα2‐3Galβ1‐3GalNAcβ1‐3Galα1‐4Galβ1‐4Glc). A partial protein sequence of the lectin was determined by mass spectrometry, and the complete sequence was identified from transcriptomic analysis. SeviL, consisting of 129 amino acids, was classified as an R(icin B)‐type lectin, based on the presence of the QxW motif characteristic of this fold. SeviL mRNA is highly expressed in gills and, in particular, mantle rim tissues. Orthologue sequences were identified in other species of the family Mytilidae, including Mytilus galloprovincialis, from which lectin MytiLec‐1 was isolated and characterized in our previous studies. Thus, mytilid species contain lectins belonging to at least two distinct families (R‐type lectins and mytilectins) that have a common β‐trefoil fold structure but differing glycan‐binding specificities. SeviL displayed notable cytotoxic (apoptotic) effects against various cultured cell lines (human breast, ovarian, and colonic cancer; dog kidney) that possess asialo‐GM1 oligosaccharide at the cell surface. This cytotoxic effect was inhibited by the presence of anti‐asialo‐GM1 oligosaccharide antibodies. With HeLa ovarian cancer cells, SeviL showed dose‐ and time‐dependent activation of kinase MKK3/6, p38 MAPK, and caspase‐3/9. The transduction pathways activated by SeviL via the glycosphingolipid oligosaccharide were triggered apoptosis.
Database
Nucleotide sequence data have been deposited in the GenBank database under accession numbers MK434191, MK434192, MK434193, MK434194, MK434195, MK434196, MK434197, MK434198, MK434199, MK434200, and MK434201.
A 15‐kDa lectin (SeviL) was isolated from the purplish bifurcate mussel, Mytilisepta virgata. SeviL binds to gangliosides and was classified as an R‐type lectin. mRNA of SeviL was expressed in gills, and this orthologue was identified in another genus Mytilus galloprovincialis from which express mytilectins. Thus, the family Mytilidae has lectins belonging to two‐distinct families sharing β‐trefoil fold but differing glycan‐binding. SeviL displayed cytotoxicity against cultured cells. The transduction pathways activated by this lectin via glycosphingolipids triggered apoptosis.