a dna-binding protein helps repair breaks in dna double helixdna结合蛋白质帮助修复断裂在dna双螺旋结构.pdfVIP

Research Digest Synopses of Research Articles A New Gene That Shapes Mouse Pigmentation Patterning Scientists have long known that variation in animal color the protein nonfunctional. The researchers made certain that patterns carry far more than cosmetic signifi cance. Darwin Tbx15 really is the droopy ear gene by deleting most of the fi rst connected pigmentation with adaptive advantage, noting gene’s coding region and showing that this “knocked-out’’ gene that male fi nches with bright red plumage enjoyed greater produces the typical droopy ear mouse. reproductive success than their drab competitors. Explaining The pattern of embryonic Tbx15 expression—determined why coloration confers such advantages, however, has proved by observing messenger RNA transcripts in developing somewhat easier than showing how it arises. Biologists studying tissues of the head, trunk, and limbs—suggests that early how neighboring regions of the vertebrate body plan develop expression of Tbx15 in the dorsal fl ank sets coordinates for differences in appearance and form dorsoventral differences in hair have identifi ed a small number length and pigmentation. Candille of signaling pathways common et al. demonstrate that the regional to all animals. How and whether pigment differences characteristic of these pathways also control the adults is indeed established soon after developmental expression and variation