Hippocampal mossy fibers induce assembly and clustering of PSD95‐containing postsynaptic densities independent of glutamate receptor activation

Journal of Comparative Neurology - Tập 440 Số 3 - Trang 284-298 - 2001
Li‐Xuan Qin1, Glen S. Marrs1,2, Ross McKim2, Michael E. Dailey1,2
1Department of Biological Sciences, University of Iowa, Iowa City, Iowa
2Program in Neuroscience, University of Iowa, Iowa City, Iowa

Tóm tắt

AbstractFactors that regulate the formation, spatial patterning, and maturation of CNS synapses are poorly understood. We used organotypic hippocampal slice cultures derived from developing (P5–P7) rat to test whether synaptic activity regulates the development and organization of postsynaptic structures at mossy fiber (MF) giant synapses. Antibodies to a prominent postsynaptic density (PSD) scaffold protein, PSD95, identified large (>1 μm) and irregularly shaped PSD assemblies that codistributed with synapsin‐I or metabotropic glutamate receptor 7b (mGluR7b) ‐immunolabeled MF terminals in area CA3. To investigate the spatial organization of synaptic PSDs on individual pyramidal cells, neurons in slice cultures were transfected with a vector encoding a GFP‐PSD95 fusion protein. Confocal three‐dimensional reconstructions revealed clusters of PSDs along proximal dendrites of transfected pyramidal neurons in area CA3, but not in CA1. Clusters averaged 7.6 μm in length (range, 2.2–29 μm) and contained up to 35 individual PSDs (mean, 8.3). PSD clusters failed to form when slices were cultured without MFs, indicating that MFs induce cluster assembly. Chronic blockade of N‐methyl‐D‐apartate– and AMPA/kainate‐type glutamate receptors did not disrupt MF targeting or de novo formation of PSD clusters with a normal distribution on target cells. Additionally, glutamate receptor blockers did not alter the ultrastructural development of MF giant synapses containing multiple puncta adherens‐like junctions and asymmetric synaptic junctions at dendritic shaft and spine domains, respectively. The results indicate that MF axons can induce the assembly and clustering of PSD95‐containing postsynaptic complexes, displaying a normal subcellular and tissue distribution, by mechanisms that are independent of ionotropic glutamate receptor activation. J. Comp. Neurol. 440:284–298, 2001. © 2001 Wiley‐Liss, Inc.

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Tài liệu tham khảo

10.1002/cne.901950106

10.1016/S0896-6273(00)80761-8

10.1073/pnas.93.10.4706

10.1002/cne.901560404

10.1002/cne.901170202

10.1002/cne.901380404

10.1002/cne.903250204

10.1016/0896-6273(92)90245-9

10.1002/cne.902460403

Craig AM, 2001, Synapses, 571

10.1016/S0896-6273(00)80705-9

10.1523/JNEUROSCI.14-03-01060.1994

10.1083/jcb.96.5.1337

10.1083/jcb.96.5.1355

DeCamilli P, 2001, Synapses, 89

10.1016/S0896-6273(00)00009-X

10.1016/0306-4522(88)90348-X

10.1007/BF00237644

10.1007/BF00238881

10.1016/0165-3806(95)00034-B

10.1002/cne.903210408

10.1002/1096-9861(20010212)430:3<357::AID-CNE1036>3.0.CO;2-K

10.1002/(SICI)1097-4547(19980301)51:5<602::AID-JNR7>3.0.CO;2-J

Hamlyn LH, 1962, The fine structure of the mossy fibre endings in the hippocampus of the rabbit, J Anat, 96, 112

10.1146/annurev.ne.17.030194.002013

10.1016/S0306-4522(00)00146-9

Husseini AE‐D, 2000, PSD‐95 involvement in maturation of excitatory synapses, Science, 290, 1364, 10.1126/science.290.5495.1364

10.1523/JNEUROSCI.18-20-08356.1998

10.1113/jphysiol.1993.sp019965

10.1126/science.274.5290.1133

10.1073/pnas.96.22.12893

10.1002/(SICI)1096-9861(19980413)393:3<332::AID-CNE6>3.0.CO;2-2

10.1016/S0021-9258(18)53433-5

10.1126/science.7569905

10.1159/000112397

10.1002/aja.1001370105

10.1016/0896-6273(94)90412-X

10.1038/nn717

Migaud M, 1998, Enhanced long‐term potentiation and impaired learning in mice with mutant postsynaptic density‐95 protein, Nature., 396, 414, 10.1038/24790

10.1523/JNEUROSCI.05-11-02909.1985

10.1016/S0165-3806(97)00132-6

10.1126/science.6438799

10.1016/0304-3940(88)90743-4

10.1016/0165-3806(96)00090-9

10.1523/JNEUROSCI.16-07-02157.1996

10.1002/cne.902390303

10.1038/12175

10.1016/0306-4522(83)90267-1

10.1016/S0896-6273(00)80962-9

10.1016/S0896-6273(00)00021-0

10.1523/JNEUROSCI.18-04-01217.1998

Reid CA, 2001, Postsynaptic calcium transients evoked by activation of individual hippocampal mossy fiber synapses, J Neurosci, 21, 2206, 10.1523/JNEUROSCI.21-07-02206.2001

10.1016/0165-3806(94)90109-0

10.1146/annurev.neuro.24.1.1

10.1523/JNEUROSCI.17-19-07503.1997

10.1113/jphysiol.1995.sp020521

10.1002/cne.901850302

10.1016/S0079-6123(08)61023-7

10.1016/0165-0270(91)90128-M

10.1046/j.1460-9568.1998.00063.x

10.1002/cne.902280310

10.1002/cne.902640102

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Journal of Comparative Neurology

Tập 440 Số 3

284-298

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