Notch分子与其配体在32D细胞分化过程中的作用

目的 探讨Notch信号传导系统的作用机制及其对造血系统的影响。方法 将报告基因TP1瞬时转染Notch－CHO和Notch2－CHO细胞后，分别加入转染有不同Notch配体Deltal,Delta4,Jagged1,Jagged2的CHO细胞及正常未转染的CHO细胞，使Notch分子与其配体充分结合并发挥作用，加入发光底物PGL－100，用Lumat测定发光情况。将Notch1－32D细胞加入含G－CSF培养液的CHO，Jagged2-CHO及Delta4-CHO细胞中，观察Notch1－32D细胞分化及分化抑制情况。结果 5种Notch配体与Notch1结合后均能引起荧光素酶活性增高，Jagged2-CHO,Delta4-CHO1-4,Delta4-CHO1-5尤为明显。对Notch2来讲，5种配体均可引起TP1活性的增高。在G－CSF存在下，Notch1－32D细胞可分化为成熟的粒细胞；通过分化抑制实验发现Jagged2能抑制G－CSF引起的Notch1－32D细胞分化，但Delta4不能抑制GCSF引起的Notch1－32D细胞分化。Jadded2,Delta4为Notch1分子的配体，Delta4不能抑制G－CSF引起的Notch1－32D细胞分化，但Jagged2能抑制G－CSF引起的Notch1－32D细胞分化。

Effects of Notch and its ligands on the differentiation of 32D cell

Objective To explore the mechanism of Notch signaling transduction system and its effects on hematopoietic system. Methods Notch ligands transfected CHO cells were added into Notch1 and Notch2 transfected CHO cells, which were transiently transfected with reporter gene TP1. PGL 100 was used as substrate to test the interaction between Notch and Notch ligands. CHO,Jagged2 CHO and Delta4 CHO cells were seeded in the petri dish containing G CSF, and then Notch 1 32D cells were added in it to observe the differentiation of Notch1 32D cell after incubation and staining.Results All of the five Notch ligands binding to Notch1 could induce TP1 activity, it increased significantly the Jagged2 CHO,Delta4 CHO1 4 and Delta4 CHO1 5 cells. For Notch2, the TP1 activity induced by the five ligands in these cells was much higher than that of CHO. At the presence of G CSF, Notch1 32D could differentiate to mature granulocyte. Jagged2 could inhibit G CSF induced Notch1 32D cell differentiation, but Delta4 could not. Conclusion Jagged2 and Delta4 are the ligands of Notch1. Jagged2 can inhibit G CSF induced Notch1 32D cell differentiation, but Delta4 can not.