近日来自华南农业大学动物科学学院的研究人员在在美国《公共科学图书馆—综合》（PLoS ONE）上发表了题为“Simulated Microgravity Compromises Mouse Oocyte Maturation by Disrupting Meiotic Spindle Organization and Inducing Cytoplasmic Blebbing”的研究论文。
文章的第一作者为华南农业大学动物科学学院吴嫦丽博士。张守全教授为这篇文章的通讯作者。该研究获得了973项目的资助。
人们一直追寻遨游太空的梦想，航天飞机的穿梭和空间站的建立使这一梦想几近实现。但是在太空环境下人类和动物是否可正常繁育，尚未有定论。
在这篇文章中，研究人员以小鼠为实验动物模型，以RWVB （旋转壁式生物反应器）提供的模拟微重力条件（0.01-0.001g），经过5年的潜心研究，发现在模拟微重力条件下哺乳动物卵母细胞的体外成熟受到明显的抑制，卵母细胞的第一极体排出率为8.95%，仅为正常重力条件下（1g）的1/8。同时，微重力条件下培养的卵母细胞形态异常率上升，有12.96%的卵母细胞出现“胞质吐泡”，13.03%的卵母细胞形成突起，而这些异常形态在1g重力条件下是鲜见的。
该研究表明模拟微重力条件下，卵母细胞难以正常排出极体是由于减数分裂过程中，微管的募集、重排受到破坏，无法形成结构完整的纺锤体，导致减数分裂过程中的染色体分离失败，极体排出受阻。模拟微重力条件下卵母细胞纺锤体的异常率高达95%，而正常重力条件下纺锤体的异常率仅为2.78%。纺锤体结构缺失的主要是微管结构，而与染色体迁移密切相关的微丝的功能并未受到显著的影响，表明微管是卵母细胞感受重力的重要细胞结构之一，在失重的环境下，微管的正常功能受到破坏。该研究揭示了小鼠卵母细胞在模拟微重力环境下由于微管组织受到破坏，难以发育为成熟的具有受精能力的卵母细胞，因而在微重力环境下，哺乳动物的生育可能会遇到很大的困难。
公共科学图书馆（PLoS）是一家由众多诺贝尔奖得主和慈善机构支持的非赢利性学术组织，旨在推广世界各地的生命科学领域的最新研究成果。PLoS出版了8种生命科学与医学领域的开放获取期刊，可以免费获取全文，在国际上享有很高的知名度和很强的学术影响力。2006 年12月20日，PLoS创建了PLoS ONE综合性在线期刊。在创刊三年时间内，2010年的影响因子达到4.411。(生物谷 Bioon.com)
生物谷推荐原文出处：
PLoS ONE DOI： 10.1371/journal.pone.0022214
Simulated Microgravity Compromises Mouse Oocyte Maturation by Disrupting Meiotic Spindle Organization and Inducing Cytoplasmic Blebbing
Changli Wu
In the present study, we discovered that mouse oocyte maturation was inhibited by simulated microgravity via disturbing spindle organization. We cultured mouse oocytes under microgravity condition simulated by NASA's rotary cell culture system, examined the maturation rate and observed the spindle morphology (organization of cytoskeleton) during the mouse oocytes meiotic maturation. While the rate of germinal vesicle breakdown did not differ between 1 g gravity and simulated microgravity, rate of oocyte maturation decreased significantly in simulated microgravity. The rate of maturation was 8.94% in simulated microgravity and was 73.0% in 1 g gravity. The results show that the maturation of mouse oocytes in vitro was inhibited by the simulated microgravity. The spindle morphology observation shows that the microtubules and chromosomes can not form a complete spindle during oocyte meiotic maturation under simulated microgravity. And the disorder of 纬-tubulin may partially result in disorganization of microtubules under simulated microgravity. These observations suggest that the meiotic spindle organization is gravity dependent. Although the spindle organization was disrupted by simulated microgravity, the function and organization of microfilaments were not pronouncedly affected by simulated microgravity. And we found that simulated microgravity induced oocytes cytoplasmic blebbing via an unknown mechanism. Transmission electron microscope detection showed that the components of the blebs were identified with the cytoplasm. Collectively, these results indicated that the simulated microgravity inhibits mouse oocyte maturation via disturbing spindle organization and inducing cytoplasmic blebbing.
