Publications by authors named "Tyler C Brown"

Perceptual success depends on fast-spiking, parvalbumin-positive interneurons (FS/PVs). However, competing theories of optimal rate and correlation in pyramidal (PYR) firing make opposing predictions regarding the underlying FS/PV dynamics. We addressed this with population calcium imaging of FS/PVs and putative PYR neurons during threshold detection.

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Synapses are fundamental information-processing units of the brain, and synaptic dysregulation is central to many brain disorders ("synaptopathies"). However, systematic annotation of synaptic genes and ontology of synaptic processes are currently lacking. We established SynGO, an interactive knowledge base that accumulates available research about synapse biology using Gene Ontology (GO) annotations to novel ontology terms: 87 synaptic locations and 179 synaptic processes.

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The strength of excitatory synaptic transmission depends partly on the number of AMPA receptors (AMPARs) at the postsynaptic surface and, thus, can be modulated by membrane trafficking events. These processes are critical for some forms of synaptic plasticity, such as long-term potentiation and long-term depression (LTD). In the case of LTD, AMPARs are internalized and dephosphorylated in response to NMDA receptor activation.

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The regulated trafficking of neurotransmitter receptors at synapses is critical for synaptic function and plasticity. However, the molecular machinery that controls active transport of receptors into synapses is largely unknown. We found that, in rat hippocampus, the insertion of AMPA receptors (AMPARs) into spines during synaptic plasticity requires a specific motor protein, which we identified as myosin Va.

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Endosomal membrane trafficking in dendritic spines is important for proper synaptic function and plasticity. However, little is known about the molecular identity and functional compartmentalization of the membrane trafficking machinery operating at the postsynaptic terminal. Here we report that the transport of AMPA-type glutamate receptors into synapses occurs in two discrete steps, and we identify the specific endosomal functions that control this process during long-term potentiation.

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Members of the Rab family of small GTPases are essential regulators of intracellular membrane sorting. Nevertheless, very little is known about the role of these proteins in the membrane trafficking processes that operate at synapses, and specifically, at postsynaptic terminals. These events include the activity-dependent exocytic and endocytic trafficking of AMPA-type glutamate receptors, which underlies long-lasting forms of synaptic plasticity such as long-term potentiation (LTP) and long-term depression (LTD).

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The activity-dependent removal of AMPA receptors from synapses underlies long-term depression in hippocampal excitatory synapses. In this study, we have investigated the role of the small GTPase Rab5 during this process. We propose that Rab5 is a critical link between the signaling cascades triggered by LTD induction and the machinery that executes the activity-dependent removal of AMPA receptors.

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