Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University, Suwon, Republic of Korea.
Department of Animal Science, Chungbuk National University, Cheongju, Republic of Korea.
Biochim Biophys Acta Mol Cell Res. 2017 Jul;1864(7):1328-1334. doi: 10.1016/j.bbamcr.2017.05.002. Epub 2017 May 2.
If no fertilization occurs for a prolonged time following ovulation, oocytes experience a time-dependent deterioration in quality both in vivo and in vitro due to processes called postovulatory aging. Because the postovulatory aging of oocytes has marked detrimental effects on embryo development and offspring, many efforts have been made to unveil the underlying mechanisms. Here we showed that translationally controlled tumor protein (TCTP) regulates spindle assembly during postovulatory aging and prevents deterioration in mouse oocyte quality. Spindle dynamics decreased with reduced TCTP level during aging of mouse oocytes. Knockdown of TCTP accelerated the reduction of spindle dynamics, accompanying with aging-related deterioration of oocyte quality. Conversely, overexpression of TCTP prevented aging-associated decline of spindle dynamics. Moreover, the aging-related abnormalities in oocytes were rescued after TCTP overexpression, thereby improving fertilization competency and subsequent embryo development. Therefore, our results demonstrate that TCTP-mediated spindle dynamics play a key role in maintaining oocyte quality during postovulatory aging and overexpression of TCTP is sufficient to prevent aging-associated abnormalities in mouse oocytes.
如果排卵后长时间未受精，卵母细胞会因称为排卵后老化的过程而在体内和体外出现质量的时间依赖性下降。由于卵母细胞的排卵后老化对胚胎发育和后代有明显的不利影响，因此人们做出了许多努力来揭示其潜在的机制。在这里，我们发现翻译控制肿瘤蛋白（TCTP）在排卵后老化过程中调节纺锤体组装，防止小鼠卵母细胞质量恶化。随着卵母细胞老化，TCTP 水平降低，纺锤体动力学也随之降低。TCTP 敲低加速了纺锤体动力学的减少，伴随着与老化相关的卵母细胞质量恶化。相反，TCTP 的过表达可防止与老化相关的纺锤体动力学下降。此外，TCTP 过表达后可挽救卵母细胞的老化相关异常，从而提高受精能力和随后的胚胎发育。因此，我们的研究结果表明，TCTP 介导的纺锤体动力学在维持排卵后老化过程中的卵母细胞质量方面发挥着关键作用，而过表达 TCTP 足以防止小鼠卵母细胞的老化相关异常。
