Dajas-Bailador Federico, Bonev Boyan, Garcez Patricia, Stanley Peter, Guillemot Francois, Papalopulu Nancy
Faculty of Life Sciences, University of Manchester, Michael Smith Building, Manchester, UK.
Nat Neurosci. 2012 May;15(5):697-699. doi: 10.1038/nn.3082. Epub 2012 Apr 8.
The capacity of neurons to develop a long axon and multiple dendrites defines neuron connectivity in the CNS. The highly conserved microRNA-9 (miR-9) is expressed in both neuronal precursors and some post-mitotic neurons, and we detected miR-9 expression in the axons of primary cortical neurons. We found that miR-9 controlled axonal extension and branching by regulating the levels of Map1b, an important protein for microtubule stability. Following microfluidic separation of the axon and the soma, we found that miR-9 repressed Map1b translation and was a functional target for the BDNF-dependent control of axon extension and branching. We propose that miR-9 links regulatory signaling processes with dynamic translation mechanisms, controlling Map1b protein levels and axon development.
神经元发育出长轴突和多个树突的能力决定了中枢神经系统中的神经元连接。高度保守的微小RNA-9（miR-9）在神经元前体和一些有丝分裂后神经元中均有表达，并且我们在原代皮层神经元的轴突中检测到了miR-9的表达。我们发现miR-9通过调节微管稳定性的重要蛋白Map1b的水平来控制轴突的延伸和分支。在对轴突和胞体进行微流控分离后，我们发现miR-9抑制Map1b的翻译，并且是轴突延伸和分支的BDNF依赖性控制的功能靶点。我们提出，miR-9将调节信号传导过程与动态翻译机制联系起来，控制Map1b蛋白水平和轴突发育。
