Evolution of a pregnancy protein in primates

摘要

New genetic functions can evolve when a transposable element (TE) carrying a regulatory region inserts itself into a gene. Deena Emera and Giinter Wagner (pp. 11246-11251) explore how TEs are fine tuned for optimal gene expression by studying a reporter gene under the control of a regulatory element known as the primate decidual prolactin promoter. The authors tested a panel of decidual prolactin promoters, which span two TEs and drive expression of the hormone prolactin in the uterus during pregnancy, from different species and found that ape promoters were more active than those from lower primates, with one TE responsible for the bulk of the difference. Seven nucleotides within the two TEs are derived and conserved in the apes, and five of these appear to have undergone positive selection in apes.