The Orientation And Expression Of JAK2 In Mouse Oocyte

JAK2 is one of the Janus kinase family.It participates in the JAK-STAT signal transduction and plays roles in signal transduction of many cytokins and growth factors such as growth hormone,Il and GM-CSF.It plays essential roles in cellular functions, i.e.cell proliferation and differentiation. JAK2 regulats gene function by the phosphorylation and translocation to nuclear of its substrate STAT. JAK2 is not found in nuclear of most somatoblasts and it only exists in the cytoplasm.However it was found that JAK2 exists in nuclear of mouse oocyte recently.We used GV and M II oocytes to detect the exist of JAK2 in nuclear via immunofluorescence. The result showed that JAK2 presents abundantly in the nuclear of mouse oocyte.The orientation of JAK2 in oocyte during the oocyte maturation was detected and found that JAK2 located in nuclear of all development phase of oocyte. By fluorescence real-time PCR ,we found that the expression quantity of JAK2 increased along with the development of oocyteWe also compared the quantity of JAK2 in GV oocytes and 2-cell embryos nuclear.The quantity of JAK2 significantly reduced in 2-cell embryo nuclear compared with GV oocytes.By nuclear transferee transfered the NIH 3T3 cell to enucleated GV and MII oocyte.The immunofluorescence results showed that JAK.2 was not transfered to somatoblast nuclear whether the recombined oocyte occured GVBD or not.When transfered somatoblast nuclear to enucleated and integrated M II oocyte,the immunofluorescence results showed that JAK2 only existed in the nuclear of integrated M II oocyte but not the somatoblast nuclear.The nuclear transfer implied that the mature and immature oocyte cytoplasm could not transfer the JAK.2 protein to donor nuclear.