Fig. 8.

Entry date and conservation of syncytin-Ten1 in the Afrotheria radiation. (Left) Afrotheria phylogenetic tree (adapted from refs. 23, 40, 41). The length of the horizontal branches is proportional to time (see the scale bar above the tree). The names of the 13 Tenrecidae species tested for the presence of the syncytin-Ten1 gene are indicated, together with the names of the corresponding families. (Right) The length (in amino acids) of the syncytin-Ten1 proteins that were identified for each species is indicated. (The sequences have been deposited in the GenBank database: accession nos. KJ934881–KJ934893.) Brackets indicate that only a partial sequence could be retrieved. c, coding sequence; −, no syncytin-Ten1 homologous sequence identified by either PCR-amplification or database search, thus dating syncytin-Ten1 acquisition back 30–70 Mya, i.e., either before or after the split between the Malagasy and the mainland Africa Tenrecidae. (The African habitats of the two groups are indicated in green in the respective maps.) The fusogenic activity of each cloned gene, as determined by a fusion assay described in Fig. 5 and Fig. S2, is provided. nr, not relevant.