Figure 8.

Structural model of a mouse CHT dimer. a, Sequence alignment between mouse and human CHT (SLC5A7) and the template vSGLT used for structural modeling studies. The secondary structure prediction (SSP) averaged over the SLC5A7 profile from HHpred server (Hildebrand et al., 2009) is shown below hSLC5A7 sequence as gray (coil), blue (helix) and red (β-strand) bars. The transmembrane topology prediction from Topcons server (Tsirigos et al., 2015) is also shown as bars below SSP colored and numbered according to the topology proposed by Faham et al. (2008). The secondary structure and transmembrane helices based on the structure of the template vSGLT are also shown on top of vSGLT sequence, similarly to that of CHT. The region between TM12 and TM13 shaded in gray was not modeled. Residues shown in the model are highlighted according to their properties; neutral in white, aromatic in yellow, polar in green, basic in blue and acidic in red. b, Hydrophobicity profiles for mSLC5A7 (red) and vSGLT (black) revealing conserved hydrophobic regions. Residues corresponding to the TM helices in vSGLT or those predicted for mSLC5A7 are indicated as black and red bars at the top of the graph and in the case of mSLC5A7 also as red shading. c, d, Final structural model of the dimeric form of mSLC5A7 and the correspondent topology. In both, TM helices are colored according to Faham et al. (2008) and the inverted repeat units are shown as orange and blue triangles.