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研究発表を行った学会；
・41st Annual Meeting for the Japanese Society of Developmental Biologists.
　2008年5月28日~30日(徳島)

タイトル；Xtr, One of The Key Proteins for Progression of Meiotic Cycle in Xenopus laevis.
　
発表者；　大神　浩幹　氏
　　　（熊本大学　大学院自然科学研究科　理学専攻生命科学講座）
Abstract；
Xtr is known to act on microtubule assembly around nucleus and karyokinesis during cleavage in Xenopus laevis. This protein occurs in germline cells as well as in early embryonic cells. Especially, a lot of Xtr are synthesized immediately after entering meiotic phase in spermatogenesis, suggesting that the Xtr also plays a role in meiotic regulation. To verify this possibility, we took advantage of microinjection into oocytes with anti-Xtr antibody for inhibiting the Xtr function. When we injected the anti-Xtr antibody into oocytes followed by reinitiation of oocyte maturation by progesterone treatment, spindle formation at meiotic metaphase was inhibited. Analyses on the distribution of the Xtr, however, did not show its localization around the spindle and chromosome. To clarify the action of the Xtr in spindle formation, we injected demembraned sperm nuclei into unfertilized egg along with co-injection of EGTA for keeping the capability of the egg to induce the sperm nuclei to form chromosome with spindle at meiotic metaphase II. When the sperm nuclei were injected into unfertilized eggs with anti-Xtr antibody, normal chromosomes accompanied with fully developed spindle were observed. On the other hand, when we injected anti-Xtr antibody into oocytes followed by reinitiation of oocyte maturation and injected the sperm nuclei into the matured oocytes, no chromosome with spindle was observed. These results clearly indicate that Xtr acts during progression of meiosis, but not in meiotic spindle formation directly.