Molecular Signalling Group, National Research Council Canada, Institute for Biological Sciences, Ottawa, Ontario, Canada.
Biochem Biophys Res Commun. 2010 Oct 22;401(3):458-62. doi: 10.1016/j.bbrc.2010.09.081. Epub 2010 Sep 25.
The densely ciliated granule cell layer of the adult murine hippocampal dentate gyrus is one of two sites of adult neurogenesis. The granule cells have already been proven to localize their SSTR3 (somatostatin receptor 3) receptors to their so-called primary cilia. Here we show for the first time that 70-90% of these cells in 7-18 months-old wild-type and 3×Tg-AD (Alzheimer disease transgenic) mice also load p75(NTR) receptors into the structures containing SSTR3, i.e., their primary cilia. On the other hand, p75(NTR')s TrkA co-receptors were not localized to cilia but conventionally distributed throughout the cell surface. Significantly fewer cells (20-40%) in the hippocampal CA1 and CA3 regions and cerebral cortex have p75(NTR) containing cilia. While we don't know what the impact of the cilial localization of p75(NTR) on dentate gyral adult neurogenesis and memory encoding might be, the cilia's amyloid β-activatable p75(NTR) receptors could be damaging or lethal to the hippocampal functioning of amyloid β-accumulating Alzheimer brain.
成年鼠海马齿状回颗粒细胞层的纤毛密集，是成年神经发生的两个部位之一。已经证实颗粒细胞将其 SSTR3（生长抑素受体 3）受体定位到其所谓的初级纤毛。在这里，我们首次表明，7-18 个月大的野生型和 3×Tg-AD（阿尔茨海默病转基因）小鼠中，70-90%的这些细胞也将 p75（NTR）受体加载到含有 SSTR3 的结构中，即它们的初级纤毛。另一方面，p75（NTR'）的 TrkA 共受体未定位到纤毛，而是常规分布在整个细胞膜表面。海马 CA1 和 CA3 区和大脑皮层中含有 p75（NTR）的纤毛的细胞要少得多（20-40%）。虽然我们不知道 p75（NTR）在齿状回成年神经发生和记忆编码中的纤毛定位的影响，但纤毛的淀粉样β激活的 p75（NTR）受体可能对淀粉样β积累的阿尔茨海默氏脑的海马功能具有破坏性或致命性。
