title: Activation of embryonic genome in chick.
abstract: The earliest stages of development in most animals are under the control of maternally inherited information. The initiation of embryonic gene expression has been reported at the mid-blastula in amphibians and the mid-2-cell stage to the early morula in mammals. In chick embryos, embryonic gene expression was detectable at stage X (morula) and showed marked activation at stage XIII (blastula) with a gradual increase thereafter. Synthesis of rRNA and tRNA was low at stage X and was already the major class of RNA at stage XIII in chick embryos. The observed upregulation of RNA synthesis seems to coincide with a period of extensive fine structural differentiation when the first major cellular migrations start and signal the formation of the primitive streak in the chick embryo.
authors.affiliation: Department of Biology, University of Patras, Greece. zagris@upatras.gr
authors.forename: N
authors.initials: N
authors.lastname: Zagris
authors.forename: K
authors.initials: K
authors.lastname: Kalantzis
authors.forename: A
authors.initials: A
authors.lastname: Guialis
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000235:genetics; D002642:Chick Embryo; D047108:Embryonic Development; D005786:Gene Expression Regulation / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D012313:RNA / Q000032:analysis; D012335:RNA, Ribosomal / Q000096:biosynthesis; D012343:RNA, Transfer / Q000096:biosynthesis; D015854:Up-Regulation / Q000235:genetics
chemical_list: D012335:RNA, Ribosomal; D012313:RNA; D012343:RNA, Transfer