| First Author | Wolfe AD | Year | 2014 |
| Journal | Gene Expr Patterns | Volume | 15 |
| Issue | 1 | Pages | 8-20 |
| PubMed ID | 24632399 | Mgi Jnum | J:210985 |
| Mgi Id | MGI:5572997 | Doi | 10.1016/j.gep.2014.02.002 |
| Citation | Wolfe AD, et al. (2014) Mixl1 localizes to putative axial stem cell reservoirs and their posterior descendants in the mouse embryo. Gene Expr Patterns 15(1):8-20 |
| abstractText | Mixl1 is thought to play important roles in formation of mesoderm and endoderm. Previously, Mixl1 expression was reported in the posterior primitive streak and allantois, but the precise spatiotemporal whereabouts of Mixl1 protein throughout gastrulation have not been elucidated. To localize Mixl1 protein, immunohistochemistry was carried out at 2-4h intervals on mouse gastrulae between primitive streak and 16-somite pair (s) stages ( approximately E6.5-9.5). Mixl1 localized to the entire primitive streak early in gastrulation. However, by headfold stages ( approximately E7.75-8.0), Mixl1 diminished within the mid-streak but remained concentrated at either end of the streak, and localized throughout midline posterior visceral endoderm. At the streak's anterior end, Mixl1 was confined to the posterior crown cells of Hensen's node, which contribute to dorsal hindgut endoderm, and the posterior notochord. In the posterior streak, Mixl1 localized to the Allantoic Core Domain (ACD), which is the source of most of the allantois and contributes to the posterior embryonic-extraembryonic interface. In addition, Mix1 co-localized with the early hematopoietic marker, Runx1, in the allantois and visceral yolk sac blood islands. During hindgut invagination (4-16s, approximately E8.5-9.5), Mixl1 localized to the hindgut lip, becoming concentrated within the midline anastomosis of the splanchnopleure, which appears to create the ventral component of the hindgut and omphalomesenteric artery. Surrounding the distal hindgut, Mixl1 identified midline cells within tailbud mesoderm. Mixl1 was also found in the posterior notochord. These findings provide a critical systematic, and tissue-level understanding of embryonic Mixl1 localization, and support its role in regulation of crucial posterior axial mesendodermal stem cell niches during embryogenesis. |
