Expression Of Notch1 And Notch4 During Early Mouse Development

ObjectiveTo investigate the expression of Notch1 and Notch4 gene and protein at the hematopoietic system in mouse early embryogenesis.MethodsThe expression of Notch1 and Notch4 mRNA and protein of the hematopoietic system from the mice embryonic aorta-gonad -mesonephros (AGM) region and fetal liver at embryonic day(E)9.5, E10.5,E11.5,E12.5 were detected by RT-PCR and Western-Blotting techniques.ResultsThe expression of Notch1 mRNA in mouse embryonic AGM decreased with the pregnancy. Notch1 mRNA was the lowest in E10.5 fetal liver,and the highest in E11.5. The expression of Notch1 protein is similar with Notch1 mRNA. The expression of AGM's Notch1 mRNA at each time point compared with fetal liver were significantly different, except Notch1 protein of AGM was significantly higher than fetal liver in E9.5 ,there was no significant difference.The expression of Notch4 signaling in E10.5 AGM area was the highest, the expression of Notch4 mRNA and protein in fetal liver decreased with prolonged pregnancy. Compared the AGM and fetal liver, Notch 4 in E9.5 and E12.5 was significant different ,and there's no difference betwwen E10.5 and E11.5.ConclusionThe Notch1 and Notch4 signals are expressed in early hematopoietic tissue of mouse embryos. With the development of hematopoietic, AGM area decreased hematopoietic capacity, Notch1 signal gradually weakened; fetal liver hematopoietic function gradually improved, Notch1 signal gradually increased, Indicate that Notch1 signal may fuction in the early age of hematopoeitic system development in mouse embryo. In E10.5, the expression of Notch4 in AGM is the strongest,and then decreased. The expression of Notch4 in fetal liver decreased with prolonged pregnancy, indicate that Notch4 signal may fuction in hematopoeitic system in mouse embryo.