title: Dynamics of anterior-posterior axis formation in the developing mouse embryo.
abstract: The development of an anterior-posterior (AP) polarity is a crucial process that in the mouse has been very difficult to analyse, because it takes place as the embryo implants within the mother. To overcome this obstacle, we have established an in-vitro culture system that allows us to follow the step-wise development of anterior visceral endoderm (AVE), critical for establishing AP polarity. Here we use this system to show that the AVE originates in the implanting blastocyst, but that additional cells subsequently acquire AVE characteristics. These 'older' and 'younger' AVE domains coalesce as the egg cylinder emerges from the blastocyst structure. Importantly, we show that AVE migration is led by cells expressing the highest levels of AVE marker, highlighting that asymmetry within the AVE domain dictates the direction of its migration. Ablation of such leading cells prevents AVE migration, suggesting that these cells are important for correct establishment of the AP axis.
authors.affiliation: Wellcome Trust/Cancer Research UK Gurdon Institute, Cambridge CB2 1QN, UK.
authors.forename: Samantha A
authors.initials: SA
authors.lastname: Morris
authors.forename: Seema
authors.initials: S
authors.lastname: Grewal
authors.forename: Florencia
authors.initials: F
authors.lastname: Barrios
authors.forename: Sameer N
authors.initials: SN
authors.lastname: Patankar
authors.forename: Bernhard
authors.initials: B
authors.lastname: Strauss
authors.forename: Lee
authors.initials: L
authors.lastname: Buttery
authors.forename: Morgan
authors.initials: M
authors.lastname: Alexander
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Shakesheff
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zernicka-Goetz
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology; D019521:Body Patterning; D002465:Cell Movement; D015509:Developmental Biology / Q000379:methods*; D046149:Embryo Culture Techniques; D004707:Endoderm / Q000378:metabolism*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008954:Models, Biological; D008957:Models, Genetic; D013997:Time Factors
chemical_list: D005819:Genetic Markers; D049452:Green Fluorescent Proteins