title: Comparative transcriptome analysis reveals vertebrate phylotypic period during organogenesis.
abstract: One of the central issues in evolutionary developmental biology is how we can formulate the relationships between evolutionary and developmental processes. Two major models have been proposed: the 'funnel-like' model, in which the earliest embryo shows the most conserved morphological pattern, followed by diversifying later stages, and the 'hourglass' model, in which constraints are imposed to conserve organogenesis stages, which is called the phylotypic period. Here we perform a quantitative comparative transcriptome analysis of several model vertebrate embryos and show that the pharyngula stage is most conserved, whereas earlier and later stages are rather divergent. These results allow us to predict approximate developmental timetables between different species, and indicate that pharyngula embryos have the most conserved gene expression profiles, which may be the source of the basic body plan of vertebrates.
authors.affiliation: Laboratory for Evolutionary Morphology, RIKEN Center for Developmental Biology, Chuo-ku, Kobe, Hyogo 650-0047, Japan. asurain@cdb.riken.jp
authors.forename: Naoki
authors.initials: N
authors.lastname: Irie
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kuratani
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001934:Branchial Region / Q000033:anatomy & histology; D002645:Chickens; D004622:Embryo, Mammalian / Q000033:anatomy & histology; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D038081:Organogenesis / Q000235:genetics*; D010802:Phylogeny; D012333:RNA, Messenger / Q000032:analysis; D014714:Vertebrates / Q000196:embryology / Q000235:genetics; D014982:Xenopus laevis; D015027:Zebrafish
chemical_list: D012333:RNA, Messenger