Alignment between teleost V1R1 (light blue) and V1R2 (blue) receptors. Dr, Ga, Ol, Tr, Tn and mouse (Mm) V1RF3 proteins are shown. Conserved residues (at least seven out of ten) are highlighted in blue. Asterisks indicate conserved residues in virtually all mouse V1Rs, and red letters correspond to the ones also conserved in teleosts. Empty squares show the position of positively selected sites in some genes of the V1r1 clade. Green boxes indicate the position of the conserved N-linked glycosylation sites (NXS/T). TM, transmembrane, IC, intracellular, EC, extracellular domains.