PDF(Pubmed)
Abstract：
The dentate gyrus, a gateway for input to the hippocampal formation, arises from progenitors in the medial telencephalic neuroepithelium adjacent to the cortical hem. Dentate progenitors navigate a complex migratory path guided by two cell populations that arise from the hem, the fimbrial glia and Cajal-Retzius (CR) cells. As the hem expresses multiple Wnt genes, we examined whether β-catenin, which mediates canonical Wnt signaling and also participates in cell adhesion, is necessary for the development of hem-derived lineages. We report that, in mice, the fimbrial glial scaffold is disorganized and CR cells are mispositioned upon hem-specific disruption of β-catenin. Consequently, the dentate migratory stream is severely affected, and the dentate gyrus fails to form. Using selective Cre drivers, we further determined that β-catenin function is required in the fimbrial glial scaffold, but not in the CR cells, for guiding the dentate migration. Our findings highlight a primary requirement for β-catenin for the organization of the fimbrial scaffold and a secondary role for this factor in dentate gyrus morphogenesis.
摘要：
齿状回,一个输入海马结构的通道，起源于皮质下摆附近的内侧端脑神经上皮的祖细胞。齿状祖细胞通过由下摆产生的两个细胞群体引导的复杂迁移路径，菌毛胶质和Cajal-Retzius（CR）细胞。由于hem表达多个Wnt基因，我们检查了β-catenin，它介导经典的Wnt信号，也参与细胞粘附，是hem衍生谱系发展所必需的。我们报告说，在老鼠身上，在hem特异性破坏β-catenin后，菌毛胶质支架紊乱，CR细胞错位。因此,齿状迁徙流受到严重影响，齿状回不能形成.使用选择性Cre驱动程序，我们进一步确定，β-连环蛋白功能需要在菌毛胶质支架，但不是在CR细胞中，用于指导齿状迁移。我们的发现强调了菌毛支架组织对β-catenin的主要要求，以及该因子在齿状回形态发生中的次要作用。
