Figure 4. A Chimpanzee GDF6 Enhancer Missing in Humans Drives Expression in the Posterior of Mouse Embryos.
(A) There are two human-specific deletions of highly conserved chimpanzee sequences in the GDF6 locus. A 1.2 Mb region of the chimpanzee chromosome 8 is shown. Red bars show the positions of a 492 bp and a 5775 bp deletions in humans, hCONDEL.305 and hCONDEL.306, respectively (McLean et al, 2011). Below: multiple species comparison of the hCONDEL.306 region (red), showing sequences aligned between chimpanzee and other mammals. Blue bar represents the chimpanzee sequence tested for enhancer activity in transgenic mice.
(B) hCONDEL.306 chimpanzee sequence drives consistent expression of lacZ reporter in the posterior of E12.5 mouse embryos.
(C) Mice with the hCONDEL.306-hsp-CreER-T2 construct were bred to floxed-ROSA26 reporter mice. Tamoxifen was administered at E9.5 and embryos were lacZ stained at E12.5, showing consistent expression patterns in the posterior of the embryo.