Phylogenetic reconstruction of the evolutionary relationship among vertebrate RXFP3/4 protein sequences.

<p>Reconstruction performed as outlined in methods with <i>G = 0.91</i> and <i>I = n/a</i>. Numbers at each node indicate the bootstrap values (only values exceeding 50% shown). Teleost rxfp3-2 underwent duplication yielding two 3R-paralogs, rxfp3-2a and rxfp3-2b, while teleostean ancestral rxfp3-3 was duplicated giving rise to typically three rxfp3-3 loci in modern teleosts: 3R generated rxfp3-3a and rxfp3-3b, while a local duplication generated rxfp3-3a1 and rxfp3-3a2. Solely in zebrafish, rxfp3-3a2 duplicated again giving rise to rxfp3-3a3, an event which appears to have occurred coincidently with the exclusive loss of rxfp4 in zebrafish.