Dataset Information

Cooperative synapse formation in the neocortex.

ABSTRACT: Neuron morphology plays an important role in defining synaptic connectivity. Clearly, only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, such axo-dendritic oppositions, termed potential synapses, must be bridged by dendritic spines to form synaptic connections. To explore the rules by which synaptic connections are formed within the constraints imposed by neuron morphology, we compared the distributions of the numbers of actual and potential synapses between pre- and postsynaptic neurons forming different laminar projections in rat barrel cortex. Quantitative comparison explicitly ruled out the hypothesis that individual synapses between neurons are formed independently of each other. Instead, the data are consistent with a cooperative scheme of synapse formation where multiple-synaptic connections between neurons are stabilized while neurons that do not establish a critical number of synapses are not likely to remain synaptically coupled.

SUBMITTER: Fares T

PROVIDER: S-EPMC2738618 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Cooperative synapse formation in the neocortex.

Fares Tarec T Stepanyants Armen A

Proceedings of the National Academy of Sciences of the United States of America 20090904 38

Neuron morphology plays an important role in defining synaptic connectivity. Clearly, only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, such axo-dendritic oppositions, termed potential synapses, must be bridged by dendritic spines to form synaptic connections. To explore the rules by which synaptic connections are formed within the constraints imposed by neuron morphology, we compared the distri ...[more]

PMID: 19805321

Similar Datasets

Project description:T lymphocyte recognition of antigenic peptides on the surface of antigen-presenting cells (APC) leads to immune synapse formation (IS). By analogy with the nervous synapse, this cell-cell communication model requires the formation of highly organized structures that delimit an active zone of membrane traffic. For T cells to connect antigen recognition with the biological response, receptors and signaling proteins must be recycled. Sorting nexin 27 (SNX27) is an endosomal protein best known for its role in recycling PDZ (PSD95, Dlg1, ZO-1)-interacting neuronal proteins via the retromer transport machinery. Alteration of this sorting pathway leads to neurodegeneration and is associated to Down syndrome, Alzheimer’s and Parkinson’s diseases. In T lymphocytes, SNX27 interacts with diacylglycerol kinase zeta (DGKz), which provides a mechanistic link between diacylglycerol metabolism and membrane trafficking. Following antigen recognition, SNX27-positive endosomes polarize to the IS and a PDZ-dependent SNX27 pool accumulates at the cell-cell contact area. To test for additional SNX27 functions, we carried out proteomic analysis of the SNX27 interactome purified from T cells in contact with APC, and identified SNX27 interaction with the retromer and with members of the WASH (Wiskott-Aldrich syndrome protein and SCAR homologue) complex. This finding indicates the conserved nature of the SNX27/WASH/retromer complex in hematopoietic cells and suggests similarity between neurological diseases and abnormal immune/inflammatory responses. We also found PDZ-dependent SNX27 cargoes, including modulators of cytoskeletal reorganization such as zona occludens-2 (ZO-2). ZO-2, a cytosolic component of epithelial cell-cell junctions, localized to the IS, and SNX27 silencing affected ZO-2 stability at the synapse. This study broadens our knowledge of SNX27 function in T lymphocytes, and suggests that pathways that delimit polarized structures in epithelial systems also participate in IS regulation.

Dataset Information

Cooperative synapse formation in the neocortex.

Publications

Cooperative synapse formation in the neocortex.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets