title: DNA dendrimers localize MyoD mRNA in presomitic tissues of the chick embryo.
abstract: MyoD expression is thought to be induced in somites in response to factors released by surrounding tissues; however, reverse transcription-PCR and cell culture analyses indicate that myogenic cells are present in the embryo before somite formation. Fluorescently labeled DNA dendrimers were used to identify MyoD expressing cells in presomitic tissues in vivo. Subpopulations of MyoD positive cells were found in the segmental plate, epiblast, mesoderm, and hypoblast. Directly after laying, the epiblast of the two layered embryo contained approximately 20 MyoD positive cells. These results demonstrate that dendrimers are precise and sensitive reagents for localizing low levels of mRNA in tissue sections and whole embryos, and that cells with myogenic potential are present in the embryo before the initiation of gastrulation.
authors.affiliation: Department of Anatomy, Philadelphia College of Osteopathic Medicine, Philadelphia, PA 19131, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gerhart
authors.forename: M
authors.initials: M
authors.lastname: Baytion
authors.forename: S
authors.initials: S
authors.lastname: DeLuca
authors.forename: R
authors.initials: R
authors.lastname: Getts
authors.forename: C
authors.initials: C
authors.lastname: Lopez
authors.forename: R
authors.initials: R
authors.lastname: Niewenhuis
authors.forename: T
authors.initials: T
authors.lastname: Nilsen
authors.forename: S
authors.initials: S
authors.lastname: Olex
authors.forename: H
authors.initials: H
authors.lastname: Weintraub
authors.forename: M
authors.initials: M
authors.lastname: George-Weinstein
mesh_terms: D000818:Animals; D002642:Chick Embryo; D015342:DNA Probes; D005775:Gastrula / Q000166:cytology; D017403:In Situ Hybridization / Q000379:methods*; D008648:Mesoderm / Q000166:cytology; D009132:Muscles / Q000166:cytology / Q000196:embryology*; D017570:MyoD Protein / Q000235:genetics / Q000302:isolation & purification*; D009218:Myosins / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000302:isolation & purification*; D019170:Somites / Q000166:cytology; D014018:Tissue Distribution
chemical_list: D015342:DNA Probes; D017570:MyoD Protein; D012333:RNA, Messenger; D009218:Myosins