日前,由四川大学生物治疗国家重点实验室/华西医院神经分子生物学实验室肖波教授带领的研究小组完成了题为“Rheb1 Is Required for mTORC1 and Myelination in Postnatal Brain Development”的学术论文。该论文发表在今年1月20日的 Developmental Cell 杂志上(Cell子刊系列杂志,5年平均IF为14.058)。
由一类名为少突胶质细胞的神经细胞形成的髓鞘对于人类大脑的信息处理过程非常重要,然而,少突胶质细胞的发育以及它们包裹轴突形成髓鞘的分子机制仍然是不清楚的。肖波教授带领几位研究生邹嘉、周亮(共同第一作者,2006级)等开展了大量的研究工作,发现Rheb/mTor信号在该过程中起着很重要的作用。由于mTor 信号在发育生物学、肿瘤研究、免疫学以及神经精神疾病的调控中的都具有重要作用,因此mTor相关研究也是生物医学竞争最为激烈的领域之一。正如评审人所说,“该研究采用了一系列强有力的研究手段如遗传修饰小鼠、生物化学以及细胞成像等来揭示生物医学研究中的一个重要科学问题,该研究详细充分地分析了Rheb/mTor信号在出生后脑发育、尤其是髓鞘形成中的作用。”该文的第一作者邹嘉表示:“在已发表的文章中,仅在一篇文章中就采用如此多种敲除敲入小鼠模型开展研究这在国内是极少见的。”肖波教授也指出:“mTor信号对髓鞘的调控作用存在争议,我们的工作首次证明了Rheb/mTor信号对髓鞘发育具有促进作用。”(生物谷Bioon.com)
生物谷推荐原文出处:
Developmental Cell doi:10.1016/j.devcel.2010.11.020
Rheb1 Is Required for mTORC1 and Myelination in Postnatal Brain Development
Jia Zou, Liang Zhou, Xiao-Xia Du, Yifei Ji, Jia Xu, Junlong Tian, Wanxiang Jiang, Yi Zou, Shouyang Yu, Lingxue Gan, Maowen Luo, Qiaona Yang, Yiyuan Cui, Wanchun Yang, Xiaoqiang Xia, Mina Chen, Xia Zhao, Ying Shen, Po Yu Chen, Paul F. Worley, Bo Xiao
Highlights
Rheb1, but not Rheb2, is essential for mTORC1 signaling
Rheb1 and Rheb2 are not essential for mTORC2 signaling
Rheb/mTORC1 signaling is a positive regulator of postnatal myelination in the brain
Summary
mTor kinase is involved in cell growth, proliferation, and differentiation. The roles of mTor activators, Rheb1 and Rheb2, have not been established in vivo. Here, we report that Rheb1, but not Rheb2, is critical for embryonic survival and mTORC1 signaling. Embryonic deletion of Rheb1 in neural progenitor cells abolishes mTORC1 signaling in developing brain and increases mTORC2 signaling. Remarkably, embryonic and early postnatal brain development appears grossly normal in these Rheb1f/f,Nes-cre mice with the notable exception of deficits of myelination. Conditional expression of Rheb1 transgene in neural progenitors increases mTORC1 activity and promotes myelination in the brain. In addition the Rheb1 transgene rescues mTORC1 signaling and hypomyelination in the Rheb1f/f,Nes-cre mice. Our study demonstrates that Rheb1 is essential for mTORC1 signaling and myelination in the brain, and suggests that mTORC1 signaling plays a role in selective cellular adaptations, rather than general cellular viability.