Studies On The Role Of Nulpl In The Formation Of Myocardial Cells

The heart is one of the earliest organs in mammalian embryonic development.The heart development includes several steps,since mature mesoderm cells to cardiac mesoderm cells,following cardiac mesoderm cells developed into heart muscle cells.So the differentiation mechanism of myocardial cell have important reference and guiding significance in treating heart disease caused by genetic factors and other heart related diseases.Wnt genes began expressed in the early stages of embryonic development,and Wnt could adjust different cellular processes,such as gene transcription,cell proliferation,mature,polarity and differentiation.In heart development process,Wnt and their receptors presented a highly heterogeneous expression at time and space,suggesting Wnt signaling plays an important role in the development of heart at the early time.Wnt signaling pathways involved in almost all phases of the development of heart that early specialization,myocardial differentiation,heart pipe ring,cell migration and proliferation,chamber and the valve formation and conduction system construction,and other links.Nulp1 is one of candidated genes of heart development screened at our laboratory before.Over the full length of the c DNA,there are 2270 bases and 2031 bases on the ORF,encoding a long protein of 676 aminoacid residues.The protein contains a b HLH structure and a structure domain with unknown function named DUF654.In species such as mice have found its homologous proteins with a very high degree of conservative,the family in which the protein is likely to have fairly important functions.Previous studies have shown that Nulp1 could inhibite the differentiation of P19 cells into myocardial cells by adjusting the Wnt signaling pathway.In this paper,we induced P19 cells using DMSO in vitro to simulate myocardial differentiation model to explore the relationship between Nulp1 and Wnt signaling pathways.To explore the influence of the Nulp1 on myocardial cell differentiation,we carried out the immunofluorescence and found that Nulp1 played the role of inhibition on myocardial differentiation of P19 cells.Then Western blot were carried out to detect the changes of the expression of Nulp1 protein during the myocardial differentiation process.The results showed that the express of Nulp1 had difference in the process of myocardial differentiation at time.Through consulting relevant literature,we selected Wnt10 b,Wnt11,APC,LEF1 and LRP5 which are Wnt signaling pathways related genes.By RT-PCR experiments,we tested the changes on the above six genes expression,the results showed that the expression of APC were changed.Nulp1 probably by regulating the expression of APC affected the Wnt signaling pathways,and then adjusted the myocardialdifferentiation of P19 cells.There is reference value to further explore the specific regulation mechanism of Wnt signaling pathway and Nulp1.In addition,this article has carried on the other aspects of research,which on the mechanism of the protective effect of Tax on oxidative stress of H9C2 cell through MAPK/HMGB1 signaling pathways.H9C2 cells were used to study the influence of Tax on the cell morphology and the level of intracellular Reactive Oxygen Species.We tested the m RNA expression of i Nitric Oxide Synthase,Oxypropionitrile and High Mobility Group Box-1 protein.At the same time,we tested the expression and phosphorylation level of the protein p38,JNK,and ERK.The results showed that the Tax could improve the morphology change of H9C2 cells and reduce the oxidative stress levels in H9C2 cells.The Tax could also activate the expression of HMGB1 and inhibit the expression of i NOS and OPN and improve the phosphorylation level of the protein related to MAPK signaling pathways in H9C2 cells.