Figure 1. Predicted transmembrane topology of OAT family.

Twelve transmembrane segments are numbered from 1 to 12. Putative extracellular loops are numbered from I to VI. The boundaries of extracellular loops are also numbered. Residues replaced by lysine are indicated inside the open circles. Potential glycosylation sites are denoted by tree-like structures. Potential phosphorylation sites are labelled as ‘P’. Transmembrane domain helices 3, 4, 7 and 8 are shown in dark grey to indicate the uncertainty of the prediction.