Figure 1: Squematic representation of claudin-9 topology showing nonpolar residues (yellow), polar charged residues (blue), nonpolar aliphatic residues (grey), polar uncharged residues (green), disulfide bond, signature sequence, function of ECLs and postranslational modifications. ECL1: extracellular loop 1, ECL2: extracellular loop 2. Image generated with TMRPres2D (Ioannis C. Spyropoulos, Theodore D. Liakopoulos, Pantelis G. Bagos and Stavros J. Hamodrakas. TMRPres2D: high quality visual representation of transmembrane protein Models. Bioinformatics. 2004. 20:3258-3260.)