| First Author | Healy AM | Year | 1995 |
| Journal | Proc Natl Acad Sci U S A | Volume | 92 |
| Issue | 3 | Pages | 850-4 |
| PubMed ID | 7846065 | Mgi Jnum | J:22630 |
| Mgi Id | MGI:70490 | Doi | 10.1073/pnas.92.3.850 |
| Citation | Healy AM, et al. (1995) Absence of the blood-clotting regulator thrombomodulin causes embryonic lethality in mice before development of a functional cardiovascular system. Proc Natl Acad Sci U S A 92(3):850-4 |
| abstractText | We have targeted the murine thrombomodulin (TM) gene in embryonic stem cells and generated embryos as well as mice with TM deficiency. The heterozygous TM-deficient (TM+/-) mice as compared to wild-type (TM+/+) littermates exhibit 50% reductions in the levels of TM mRNA and TM protein. However, TM+/- mice appear normal and are free of thrombotic complications. The homozygous TM-deficient (TM-/-) embryos die before embryonic day 9.5. An overall retardation in growth and development of TM-/- embryos is first evident on embryonic day 8.5 (8-12 somite pairs). However, no specific pathologic abnormalities are observed. These initial changes take place at a time when TM is normally expressed in the parietal yolk sac. The removal of embryonic day 7.5 TM-/- embryos from maternal decidua and their subsequent culture in vitro allow development to proceed to stages not observed in vivo (13-20 somite pairs) with the appearance of normal blood vessels in the visceral yolk sac and embryo. The results of our studies suggest that the failure of TM-/- embryos to survive at mid-gestation is a consequence of dysfunctional maternal-embryonic interactions caused by the absence of TM in the parietal yolk sac and demonstrate that the receptor is necessary for normal embryonic development in utero. |
