# Role of Protein Glycoslation in Host-Pathogen Interaction
## 7 Lectin, a Class of Protein Entangled with Glycoprotein, Affects Host-Pathogen Interactions
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Family**} & **Subcellular** & **Carbohydrate-Binding** & **Main Function** & **Reference** \\  & **Localization** & **Specificity** & **Main Function** & **Reference** \\ \hline \multicolumn{5}{c}{Animals} \\ \hline \multirow{3}{*}{Calnexins} & Endoplasmic reticulum (ER), cell membrane & Glc\({}_{1}\)Man\({}_{9}\) oligosaccharide & Molecular chaperones during glycoprotein synthesis & [121, 122, 123] \\ \cline{2-5}  & ER, Golgi, ER-Golgi intermediate compartment & High-mannose \(N\)-glycans & Protein sorting in the endoplasmic reticulum & [124, 125] \\ \hline \multirow{3}{*}{P-type lectins} & Cell membrane, trans-Golgi network, endosomes & 6-phosphorylated mannose & Intracellular routing of glycoloconjugates & [126, 127, 128, 129, 130] \\ \cline{2-5}  & Cell membrane, extracellular & \(N\)- or O-glycans & Cell adhesion, glycoprotein clearance, and innate immunity & [39, 131] \\ \hline \multirow{3}{*}{Galectins (S-type lectins)} & Cytoplasm, cell membrane, nuclear extracellular & Galactose, GalNAc, mannose & Cellular growth regulation and extracellular & [72, 132, 133, 134, 135, 136] \\ \cline{2-5}  & Cell membrane & \(N\)-linked on L1 (cis) & Cell adhesion & [137, 138, 139] \\ \cline{2-5}  & Cell membrane & \(N\)-glycans contain fucose & & Enzyme targeting, glycoprotein hormone turnover. & [140, 141, 142] \\ \hline \multirow{3}{*}{F-box lectins} & Golgi, cell membrane & Galactose, GalNAc & Degradation of misfolded glycoproteins. & [143] \\ \cline{2-5}  & Membrane & GlcNAc\({}_{2}\) & Self/non-self recognition & [144, 145] \\ \hline \multirow{3}{*}{Chitinase-like lectins} & Cell membrane, extracellular & Chito-oligosaccharides & Development, tissue remodelling and inflammation & [146, 147, 148] \\ \cline{2-5}  & Cell membrane, extracellular & Glycans terminal with fucose & Innate immunity & [149, 150] \\ \hline \multirow{3}{*}{Inelections} & Extracellular, cell membrane & Gal, galactofuranose, pentoses & Fertilization and embryogenesis. & [151, 152, 153] \\ \cline{2-5}  & & Plants & & \\ \hline \multicolumn{5}{c}{_Agaricus_} \\ _bigorus_ & Nucleus, cytoplasm, cell wall & Glycans contain Gal or/and & & \\ agglutinism homologs & cell wall & GalNAc & Undetermined & [154, 155, 156] \\ \hline \multirow{3}{*}{Amaranthin} & Nucleus, cytoplasm & Gal-\(\beta\)(1,\(\lambda\)) GalNAc & Anti phytophagous and/or herbivous animals & [157, 158, 159] \\ \cline{2-5}  & \multirow{3}{*}{Undetermined} & High mannose \(N\)-glycans & & \\ \cline{2-5}  & & comprising the proximal & Defense response and & \\ \cline{2-5}  & lectins & pentaaccharide structure & host-microbe interaction & [160, 161] \\ \hline \multirow{3}{*}{Cyanovirin-N} & Undetermined & High-mannose type & & \\ \cline{2-5}  & \multirow{3}{*}{Undetermined} & \(N\)-glycans & Undetermined & [162] \\ \hline \multirow{3}{*}{Euonymous lectin} & \multirow{3}{*}{Nucleus, cytoplasm} & Blood group B & \multirow{3}{*}{Regulate gene expression} & [163, 164, 165] \\  & & oligosaccharides, & & \\ \cline{1-1}  & & high-mannose \(N\)-glycans & & \\ \hline \multicolumn{5}{c}{_Galantulus_} \\ _nivalis_ & Nucleus, cytoplasm & Mannose, oligomanosides, & & \\ \cline{1-1}  & vacuolar & high-mannose and/or & Undetermined & [166, 167, 168] \\ \cline{1-1}  & & complex type \(N\)-glycans & & \\ \hline \end{tabular}
\end{table} 
Table 2: The lectin families in animals and plants. Lectins have a variety of functions in vivo, such as participating in host-pathogen interaction [72; 182], inhibiting nutrition absorption [189], intercellular recognition [190], cell migration [191] and signal transduction [111]. These functions rely on the sugar-binding activity of lectins. During the host-pathogen interaction, lectins have an entangled relationship to glycoproteins. Except for some cases (e.g., capsid proteins of noroviruses [59], chitinase-like lectins [160; 161] and galectins [192]), many immature lectins are covalently bound to the glycans.