Study On The Effect Of Zbtb1 Gene On The Development And Differentiation Of Lymphocytes Cells In Mice

BTB-ZF(Broad complex,tramtrack,and Bric a brac-zinc finger)transcription factor family plays an important role in the lineage determination of immune cell development.Zbtb1,a member of the family,is important for the development of T cells,and also partly affects the development of B cells and NK cells.A point mutation of Zbtb1 gene in BTB domain(ScanT mutant)and the deletion of Zbtb1 gene resulted in the almost complete disappearance of T cells in mice.IL-7 is an important factor to maintain the survival of thymocytes and the normal development of T cells.Its receptor ? chain can mutally affect Zbtb1 gene during T cell development.The purpose of this study was to explore the role of Zbtb1 gene on the development and differention of mouse lympfocytes cells,which mainly included two parts: first,Zbtb1 gene promotes lymphoid development and inhibits myeloid generation in mice;second,mechanism of interaction between Zbtb1 gene and IL-7R? during T cell development.The contents of the study are summarized as follows:1.In this study,wild type and mutant(ScanT)mice of Zbtb1 gene were used as research materials.The following experimental results were obtained by flow cytometry and RT-qPCR.The results showed that Zbtb1 wild type hematopoietic stem cells could differentiate into lymphocytes in OP9/OP-DL1 system(B ? T cells),ScanT mice hematopoietic stem cells developed into myeloid cells under the condition of lymphocyte induction in vitro).Overexpression of Zbtb1 gene in wild type hematopoietic stem cell(LSK)can inhibit the development of myeloid cells induced in vitro.In conclusion,Zbtb1 gene can promote the development of lymphocytes and inhibit the differentiation of myeloid cells.2.In this study,Zbtb1 gene wild type and mutant(ScanT)mice were used to determine the effect of Zbtb1 deletion on the expression of IL-7R? during the development of T cells in mice.The effect of overexpression of Zbtb1 on the expression of IL-7R? was clarified in vitro and in vivo.The results showed that the expression of Zbtb1 reached the peak in D1 cell line in vitro when there was no IL-7 overnight,but the expression of Zbtb1 reached the lowest level after 4 hours of IL-7 re-stimulation.IL-7 was removed overnight from D1 cell culture medium and re-stimulated with different concentrations of IL-7.The level of IL-7R? on the cell surface at different time after stimulation was analyzed.It was found that the overexpression of Zbtb1 could down-regulate the expression of IL-7R? at suboptimal IL-7 concentration.In animal experiments,we found that Zbtb1 gene was overexpressed in D2 line of hCD2-Zbtb1 transgenic mice.It is concluded that Zbtb1 and IL-7R? signals can regulate and inhibit each other during T cell development.