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Abundant Self-Amplifying Intermediate Progenitors in the Subventricular Zone of the Chinese Tree Shrew Neocortex.
中国树鼩新皮层脑室下区丰富的自放大中间祖细胞。
- 影响因子:5.63
- DOI:10.1093/cercor/bhz315
- 作者列表:"Yin C","Zhou X","Yao YG","Wang W","Wu Q","Wang X
- 发表时间:2020-02-20
Abstract
:During evolution, neural progenitor cells in the subventricular zone (SVZ) have fundamental functions, ranging from brain volume expansion to the generation of a six-layered neocortex. In lissencephalic animal models, such as rodents, the majority of neural progenitors in the SVZ are intermediate progenitor cells (IPCs). Most IPCs in rodents undergo neurogenic division, and only a small portion of them divide a very limited number of times to generate a few neurons. Meanwhile, in gyrencephalic animals, such as primates, IPCs are able to self-renew for up to five successive divisions. However, abundant IPCs with successive proliferative capacity have not been directly observed in nonprimate species. In this study, we examined the development of neural progenitors in the Chinese tree shrew (Tupaia belangeri chinensis), a lissencephalic animal with closer affinity than rodents to primates. We identified an expansion of the SVZ and the presence of outer radial glial (oRG) cells in the neocortex. We also found that IPCs have the capacity to self-amplify multiple times and therefore serve as major proliferative progenitors. To our knowledge, our study provides the first direct evidence of abundant IPCs with proliferative potential in a nonprimate species, further supporting the key role of IPCs in brain expansion.
摘要
: 在进化过程中,脑室下区 (SVZ) 的神经祖细胞具有基本功能,从脑容量扩张到六层新皮质的产生。在鼠类动物模型中,SVZ 中的大多数神经祖细胞是中间祖细胞 (IPCs)。大多数啮齿类动物的 IPCs 会发生神经源性分裂,其中只有一小部分分裂非常有限的次数产生少数神经元。同时,在回脑动物中,如灵长类动物,IPCs 能够自我更新长达五个连续的分裂。然而,在非灵长类物种中尚未直接观察到具有连续增殖能力的丰富 IPCs。在这项研究中,我们检测了中国树鼩 (Tupaia belangeri chinensis) 神经祖细胞的发育,这是一种比啮齿类动物与灵长类动物更接近的 ss脑动物。我们确定了 SVZ 的扩增和新皮层中存在外放射状胶质 (oRG) 细胞。我们还发现 IPCs 具有多次自我扩增的能力,因此可作为主要的增殖祖细胞。据我们所知,我们的研究提供了大量 IPCs 在非灵长类物种中具有增殖潜力的第一个直接证据,进一步支持了 IPCs 在脑扩张中的关键作用。
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