Stage XIV tubule pieces were incubated for 1 h in the medium with ZM447439 or DMSO just before test fixation and immunofluorescent detection of phosphorylated histone H3. All control prometaphase and metaphase meiocytes showed strong phosphorylation of histone H3 on chromatin, while anaphase cells didn’t. Treatment of dividing meiocytes with 20 uM ZM447439 decreased phospho H3 labeling of pre anaphase cells by 78% in comparison to controls. We also tried the aftereffect of ZM447439 around the expression of Mitotic Centromere Associated Kinesin, yet another known substrate of Aurora B, and found that natural product library ZM447439 treatment removed MCAK from meiotic kinetochores. This observation fits with data from Xenopus egg extracts where Aurora T activity is needed to target MCAK to centromeres. Together, these results suggest that ZM447439 inhibits both Aurora A and Aurora B in cultured testicular tubule segments. To verify the monoclonal antibody against Aurora W in testis, we performed immunoblot analysis of cell extracts prepared from the whole testis and probed them together with the antibody. An important protein band at?41 kDa was observed. This molecular size corresponds to the size of Aurora B in mitotic HeLa cells. A more detailed analysis unmasked that Aurora B was indicated at a low basal level throughout the rat seminiferous pattern, and the expression levels peaked at point XIV containing the meiotic divisions. The expression is probably located in the mitotically dividing spermatogonia which are contained in many of the stages of the seminiferous cycle. By utilizing testicular cell monolayer supplements from phase XIV tubule segments and subsequent immunofluorescent staining with Aurora W antibody, we discovered a rigorous Aurora T labeling at the inner centromeres and a faint labeling at the chromosome arms in both mitotically dividing spermatogonia and meiotically dividing spermatocytes. We conclude that the size of the found meiotic protein and its subcellular localization correspond with that of Aurora B in various mitotic tissue culture cells as well as Bicalutamide Cosudex in mouse spermatocytes. To examine results of the inhibition of Aurora kinases to the development of meiotic divisions, we incubated level XIV tubule segments for 16 h both having a microtubule depolymerizing drug nocodazole, a stabilizing drug taxol, ZM447439, a of nocodazole and ZM447439, a of taxol and ZM447439, or DMSO. In somatic cells, the microtubule drugs have been proven to hyperactivate the spindle checkpoint and charge the cell cycle at the M phase in response to errors in the microtubule?kinetochore parts and inter kinetochore anxiety. In our study, monolayers of living spermatocytes were organized and examined under phase contrast microscopy after having a 16 hour incubation with one of these drugs.