AMPA receptors regulate experience-dependent dendritic arbor growth in vivo

Haas, K., Li, J., Cline, H. T. (2006) AMPA receptors regulate experience-dependent dendritic arbor growth in vivo. PNAS, 103 (32). pp. 12127-12131.

URL: http://www.pnas.org/cgi/content/abstract/103/32/12...
DOI: 10.1073/pnas.0602670103

Abstract

The size and shape of neuronal dendritic arbors affect the number and type of synaptic inputs, as well as the complexity and function of brain circuits. In the intact brain, dendritic arbor growth and the development of excitatory glutamatergic synapse are concurrent. Consequently, it has been difficult to resolve whether synaptic inputs drive dendritic arbor development. Here, we test the role of AMPA receptor (AMPAR)-mediated glutamatergic transmission in dendrite growth by expressing peptides corresponding to the intracellular C-terminal domains of AMPAR subunits GluR1 (GluR1Ct) and GluR2 (GluR2Ct) in optic tectal neurons of the Xenopus retinotectal system. These peptides significantly reduce AMPAR synaptic transmission in transfected neurons while leaving visual system circuitry intact. Daily in vivo imaging over 5 days revealed that GluR1Ct or GluR2Ct expression dramatically impaired dendrite growth, resulting in less complex arbors than controls. Time-lapse images collected at 2-h intervals over 6 h show that both GluR1Ct and GluR2Ct decrease branch lifetimes. Ultrastructural analysis indicates that synapses formed onto neurons expressing the GluRCt are less mature than synapses onto control neurons. These data suggest that the failure to form complex arbors is due to reduced stabilization of new synapses and dendritic branches. Although visual stimulation increases dendritic arbor growth rates in control tectal neurons, a weak postsynaptic response to visual experience in GluRCt-expressing cells leads to retraction of branches. These results indicate that AMPAR-mediated transmission underlies experience-dependent dendritic arbor growth by stabilizing branches, and support a competition-based model for dendrite growth.

Item Type: Paper
Uncontrolled Keywords: Animals Dendrites metabolism physiology Electrophysiology Neurons metabolism pathology Peptides chemistry Protein Structure Tertiary Receptors AMPA physiology Receptors Glutamate metabolism Synapses metabolism Synaptic Transmission Time Factors Xenopus laevis
Subjects: bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > AMPA receptor
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors

organs, tissues, organelles, cell types and functions > sub-cellular tissues: types and functions > synapse
CSHL Authors:
Communities: CSHL labs > Cline lab
Depositing User: CSHL Librarian
Date Deposited: 15 Dec 2011 15:26
Last Modified: 15 Dec 2011 15:26
URI: http://repository.cshl.edu/id/eprint/22808

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