STELLA collaborates in distinct mesendodermal cell subpopulations at the fetal-placental interface in the mouse gastrula.
The allantois-derived umbilical component of the chorio-allantoic placenta shuttles fetal blood to and from the chorion, thereby ensuring fetal-maternal exchange. The progenitor populations that establish and supply the fetal-umbilical interface lie, in part, within the base of the allantois, where the germ line is claimed to segregate from the soma. Results of recent studies in the mouse have reported that STELLA (DPPA-3, PGC7) co-localizes with PRDM1 (BLIMP1), the bimolecular signature of putative primordial germ cells (PGCs) throughout the fetal-placental interface. Thus, if PGCs form extragonadally within the posterior region of the mammal, they cannot be distinguished from the soma on the basis of these proteins. We used immunohistochemistry, immunofluorescence, and confocal microscopy of the mouse gastrula to co-localize STELLA with a variety of gene products, including pluripotency factor OCT-3/4, mesendoderm-associated T and MIXl1, mesendoderm- and endoderm-associated FOXa2 and hematopoietic factor Runx1. While a subpopulation of cells localizing OCT-3/4 was always found independently of STELLA, STELLA always co-localized with OCT-3/4. Despite previous reports that T is involved in specification of the germ line, co-localization of STELLA and T was detected only in a small subset of cells in the base of the allantois. Slightly later in the hindgut lip, STELLA+/(OCT-3/4+) co-localized with FOXa2, as well as with RUNX1, indicative of definitive endoderm and hemangioblasts, respectively. STELLA was never found with MIXl1. On the basis of these and previous results, we conclude that STELLA identifies at least five distinct cell subpopulations within the allantois and hindgut, where they may be involved in mesendodermal differentiation and hematopoiesis at the posterior embryonic-extraembryonic interface. These data provide a new point of departure for understanding STELLA's potential roles in building the fetal-placental connection.
Department of Pediatrics, Division of Pediatric Hematology, Oncology & Bone Marrow Transplant, University of Wisconsin-Madison School of Medicine and Public Health, 1111 Highland Avenue, 4105 WIMR, Madison, WI 53705, United States.
Adam D
AD
Wolfe
Department of Cell and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, 1300 University Ave, Madison, WI 53706, United States.
Adriana M
AM
Rodriguez
Department of Cell and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, 1300 University Ave, Madison, WI 53706, United States.
Karen M
KM
Downs
D000482:Allantois / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D000818:Animals; D002868:Chromosomal Proteins, Non-Histone; D050676:Core Binding Factor Alpha 2 Subunit / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D004707:Endoderm / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D005260:Female; D005326:Fetal Proteins / Q000378:metabolism; D005333:Fetus / Q000196:embryology / Q000378:metabolism; D005775:Gastrula / Q000196:embryology / Q000378:metabolism*; D051542:Hepatocyte Nuclear Factor 3-beta / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D018613:Microscopy, Confocal; D050814:Octamer Transcription Factor-3 / Q000378:metabolism; D010920:Placenta / Q000196:embryology / Q000378:metabolism; D000074462:Positive Regulatory Domain I-Binding Factor 1; D011247:Pregnancy; D012097:Repressor Proteins / Q000378:metabolism*; D020825:T-Box Domain Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D000098908:Brachyury Protein
D002868:Chromosomal Proteins, Non-Histone; D050676:Core Binding Factor Alpha 2 Subunit; D005326:Fetal Proteins; D051542:Hepatocyte Nuclear Factor 3-beta; D018398:Homeodomain Proteins; D050814:Octamer Transcription Factor-3; D000074462:Positive Regulatory Domain I-Binding Factor 1; D012097:Repressor Proteins; D020825:T-Box Domain Proteins; D014157:Transcription Factors; D000098908:Brachyury Protein; C462180:Dppa3 protein, mouse; C496503:Foxa2 protein, mouse; C464781:Mixl1 protein, mouse; C513258:Prdm1 protein, mouse; C493726:Runx1 protein, mouse
Allantois; Brachyury; FOXa2; Hindgut; MIXl1; OCT-3/4; Primitive streak; Primordial germ cells; Runx1; STELLA