Polysialic acid and the formation of oculomotor synapses on chick ciliary neurons.
Polysialic acid and the formation of oculomotor synapses on chick ciliary neurons.
复制标题
聚唾液酸与小鸡睫状神经元动眼神经突触的形成。
DOI：
10.1002/cne.10199
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Rutishauser,Urs
中科院分区：
文献类型：
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作者：
Brusés,JuanL;Chauvet,Norbert;Rubio,MariaE;Rutishauser,Urs
The polysialic acid (PSA) moiety of the neural cell adhesion molecule (NCAM) participates in a variety of developmental processes, including axonal guidance and cell migration. PSA's function in these contexts stems from its ability to reduce cell interactions. The present study examines the regulation of PSA expression during formation of the calyciform synapse by the oculomotor axons on chick ciliary neurons. Prior to synaptogenesis, PSA is abundantly and uniformly expressed on the surface of the ciliary neuron body. However, at the time synaptic bonds start to form, as reflected in the localized accumulation of synaptic vesicles, PSA is lost from the point of synaptic contact. Thereafter, PSA is progressively lost from the ciliary neuron surface as the calyx grows. The dense mats of pseudodendritic‐like somatic spines, which extend from the postsynaptic cell body, form an exception. These spines, which are known to undergo morphological remodeling, retain PSA expression until the end of embryogenesis. The experimental removal of PSA did not affect synaptogenesis itself, in that no significant changes were observed in the surface covered by the calyx, the number of spine aggregates, the size of acetylcholine receptor clusters, the cell surface area covered by these receptors, or the ultrastructure of the calyx, spine mats, and active zones. Together, these observations suggest that the synapse eliminates PSA as a part of its normal development and that the loss of PSA from the site of axon‐target interaction may serve to stabilize structures formed during synaptogenesis. J. Comp. Neurol. 446:244–256, 2002. © 2002 Wiley‐Liss, Inc.
