The Effect Of Sympk Gene On Reproductive Function In Mice And Its Preliminary Mechanism

In mammals, the male animal’s sperm and female animal’s ovum are both developed from primordial germ cells. Spermatogenesis, including the proliferation of spermatogonium, spermatocyte meiosis and sperm cell deformation, is a highly specific differentiation process. One of the most important features of spermatogenic cell gene expression is producing cell specific mRNAs by selective polyadenylation, and usually is the use of non canonical AAUAAA independent of polyadenylation signal pathway. Studies have shown that spermatogenic cells seem to prefer to choose polyadenylation than somatic cells and a large number of spermatogenic cell transcription have shorter 3’UTR compared with somatic cell transcription, which shows that it preferentially utilizes more proximal polyadenylation sites in the spermatogenic cells.In early proteomics work of our lab, we constructed multiple lineages of spermatogenesis related protein expression and from the tetraploid germ cell lineages, we identified the gene Sympk, and put more attention to it. Reported in the literature in the somatic cells of the classical polyadenylation pathway, SYMPK, as a scaffold protein, coordinates the CPSF and CSTF interaction.But in the process of spermatogenesis, whether Sympk participated in the germ cell specific polyadenylation pathway, and the difference between the non classical polyadenylation pathway and somatic pathways, and whether there are any specific interaction of the protein, these problems prompted us study the function of Sympk in mouse spermatogenesisThis study focused on the expression of Sympk in mice at different period by the study of quantitative (Real time PCR) and localization (immunohistochemistry and fluorescence). At the same time, the introduction of two loxP sites was similar to heterozygous for Sympk gene knock out in the mice.During the propagating in the process, we found that the Knock Out mice gave birth to no homozygous mice, which does not accord with Mendel’s theorem, so we speculated that mice homozygous lethal at embryonic stage. We further constructed a Conditional Knock Out mice (CKO) with the heterozygous mice and the mice with a specific DDX4-Cre. We confirmed the male sterile phenotype in adult mice, but in the newborn CKO mouse, we can see the essence of the spermatogonium cell. Then we further analyzed phenotype appearing time,2 weeks in testis of mice born in seminiferous tubule appeared a massive vacuolization. And in mouse testis of 1 week, although there was no obvious change in seminiferous tubule, the number of sperm cells have begun to decline. Therefore, we identifid the phenotype initially to lweek in mice. At present, we are taking the organization of lweek as a sample for the analysis of RNA microarray data. We hope that the microarray results can be identified down-regulation of related genes induced by the significant changes in the expression of genes with Sympk, and try to contact with polyadenylation mechanism, elaborating the specific polyadenylation pathway of gene Sympk in spermatogenesis.