title: Cooperation of endoderm-derived BMP2 and extraembryonic ectoderm-derived BMP4 in primordial germ cell generation in the mouse.
abstract: The primordial germ cells (PGCs) of the mouse are derived from proximal epiblast cells that are adjacent to the extraembryonic ectoderm during gastrulation. Previous studies have demonstrated that extraembryonic ectoderm-derived BMP4 and BMP8B are both required for PGC generation. Here we show that Bmp2, a member of the Dpp class of the Bmp superfamily, also plays a role in PGC generation. PGC number is significantly reduced in Bmp2 heterozygous and homozygous embryos at the N2 generation onto C57BL/6 background. Bmp2 homozygous embryos also have a short allantois and about 50% of them do not undergo normal chorioallantoic fusion. Using whole-mount in situ hybridization, we show that Bmp2 is primarily expressed in the endoderm of mouse pregastrula and gastrula embryos. Using a genetic approach, we further show that Bmp2 and Bmp4, but not Bmp2 and Bmp8b, have an additive effect on PGC generation. These results suggest that PGC generation in the mouse embryo is regulated not only by extraembryonic ectoderm-derived BMP4 and BMP8B, but also by endoderm-derived BMP2.
authors.affiliation: Department of Pathobiology, University of Missouri College of Veterinary Medicine, Columbia, Missouri 65211, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Ying
authors.forename: G Q
authors.initials: GQ
authors.lastname: Zhao
mesh_terms: D000482:Allantois / Q000002:abnormalities; D000818:Animals; D001483:Base Sequence; D055396:Bone Morphogenetic Protein 2; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000378:metabolism*; D002452:Cell Count; D017931:DNA Primers / Q000235:genetics; D004065:Digestive System Abnormalities / Q000235:genetics; D004475:Ectoderm / Q000166:cytology / Q000378:metabolism*; D004707:Endoderm / Q000166:cytology / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D005854:Germ Cells / Q000166:cytology* / Q000378:metabolism*; D006579:Heterozygote; D006720:Homozygote; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016212:Transforming Growth Factor beta
chemical_list: C525719:Bmp2 protein, mouse; C525810:Bmp4 protein, mouse; C485772:Bmp8a protein, mouse; D055396:Bone Morphogenetic Protein 2; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D017931:DNA Primers; D016212:Transforming Growth Factor beta