Local Control of AMPA Receptor Trafficking at the Postsynaptic Terminal by a Small GTPase of the Rab Family

Abstract

The delivery of neurotransmitter receptors into the synaptic membrane is essential for synaptic function and plasticity. However, the molecular mechanisms of these specialized trafficking events and their integration with the intracellular membrane transport machinery are virtually unknown. Here, we have investigated the role of the Rab family of membrane sorting proteins in the late stages of receptor trafficking into the postsynaptic membrane. We have identified Rab8, a vesicular transport protein associated with trans-Golgi network membranes, as a critical component of the cellular machinery that delivers AMPA-type glutamatergic receptors (AMPARs) into synapses. Using electron microscopic techniques, we have found that is in the synaptic the postsynaptic that is for the synaptic delivery of and receptor is for delivery into the for receptor transport the into the for delivery into the the delivery of into synapses. a role for the cellular machinery in the of synaptic function and the postsynaptic membrane. The delivery of neurotransmitter receptors into the synaptic membrane is essential for synaptic function and plasticity. However, the molecular mechanisms of these specialized trafficking events and their integration with the intracellular membrane transport machinery are virtually unknown. Here, we have investigated the role of the Rab family of membrane sorting proteins in the late stages of receptor trafficking into the postsynaptic membrane. We have identified Rab8, a vesicular transport protein associated with trans-Golgi network membranes, as a critical component of the cellular machinery that delivers AMPA-type glutamatergic receptors (AMPARs) into synapses. Using electron microscopic techniques, we have found that is in the synaptic the postsynaptic that is for the synaptic delivery of and receptor is for delivery into the for receptor transport the into the for delivery into the the delivery of into synapses. a role for the cellular machinery in the of synaptic function and the postsynaptic membrane. is critical for the and of in the and is of as the cellular for and synaptic and is the and delivery of neurotransmitter receptors into synapses. However, is of the that neurotransmitter receptors into the postsynaptic membrane. these specialized trafficking events are with the intracellular membrane transport of membrane trafficking the neurotransmitter the in and AMPA-type glutamatergic receptors (AMPARs) AMPA-type glutamatergic protein AMPA-type glutamatergic protein are of synapses. in and of the synaptic membrane in and trafficking is synaptic and in are of of receptor are in receptor receptor synaptic and in and of in a of synaptic and trafficking have as and However, the cellular and molecular mechanisms membrane transport in these are of the Rab family of are of intracellular membrane sorting in are membrane transport Rab proteins are for function in Rab protein in is a of family the of neurotransmitter with the membrane and of synaptic the role of Rab proteins in neurotransmitter receptor and synaptic function the postsynaptic of the Rab family are in delivery into the Rab8, and and the transport of trans-Golgi into of the membrane. is in the into the membrane transport late and trans-Golgi network Rab proteins late stages of the trafficking into the membrane and are receptor into the postsynaptic we have the role of these Rab proteins in synaptic function and in in the late trafficking events that into synapses. 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