Javaherian Ashkan, Cline Hollis T
Graduate Program in Genetics, Stony Brook University, Stony Brook, New York 11790, USA.
Neuron. 2005 Feb 17;45(4):505-12. doi: 10.1016/j.neuron.2004.12.051.
We have used in vivo time-lapse two-photon imaging of single motor neuron axons labeled with GFP combined with labeling of presynaptic vesicle clusters and postsynaptic acetylcholine receptors in Xenopus laevis tadpoles to determine the dynamic rearrangement of individual axon branches and synaptogenesis during motor axon arbor development. Control GFP-labeled axons are highly dynamic during the period when axon arbors are elaborating. Axon branches emerge from sites of synaptic vesicle clusters. These data indicate that motor neuron axon elaboration and synaptogenesis are concurrent and iterative. We tested the role of Candidate Plasticity Gene 15 (CPG15, also known as Neuritin), an activity-regulated gene that is expressed in the developing motor neurons in this process. CPG15 expression enhances the development of motor neuron axon arbors by promoting neuromuscular synaptogenesis and by increasing the addition of new axon branches.
我们利用体内延时双光子成像技术，对非洲爪蟾蝌蚪中用绿色荧光蛋白（GFP）标记的单个运动神经元轴突进行成像，并结合对突触前囊泡簇和突触后乙酰胆碱受体的标记，以确定运动轴突树突发育过程中单个轴突分支的动态重排和突触形成。在轴突树突形成的时期，对照GFP标记的轴突具有高度动态性。轴突分支从突触前囊泡簇的位点出现。这些数据表明运动神经元轴突形成和突触形成是同时发生且反复进行的。我们测试了候选可塑性基因15（CPG15，也称为神经素）的作用，该基因是一种活性调节基因，在此过程中在发育中的运动神经元中表达。CPG15的表达通过促进神经肌肉突触形成和增加新轴突分支的添加来增强运动神经元轴突树突的发育。
