postsynaptic recycling endosome

Definition

Target type: cellularcomponent

A recycling endosome of the postsynapse. In postsynaptic terminals with dendritic spines, it is typically located at the base of a dendritic spine. It is involved in recycling of neurotransmitter receptors to the postsynaptic membrane. In some cases at least, this recycling is activated by postsynaptic signaling and so can play a role in long term potentiation. [PMID:20820847]

The postsynaptic recycling endosome is a specialized membrane-bound compartment within the postsynaptic neuron that plays a crucial role in the rapid and efficient recycling of synaptic vesicles. It is a dynamic structure that undergoes constant fission and fusion events, enabling the continuous replenishment of synaptic vesicles at the synapse.

**Key features of the postsynaptic recycling endosome:**

* **Location:** It is located in the postsynaptic dendrite, often in close proximity to the postsynaptic density (PSD) and the active zone of the presynaptic terminal.
* **Morphology:** The recycling endosome is a small, spherical or tubular compartment that is often associated with a network of interconnected tubules.
* **Composition:** It is enriched in specific proteins, including:
* **Rab proteins:** Rab5 and Rab11, which regulate the trafficking and fusion of vesicles.
* **SNARE proteins:** Synaptobrevin, syntaxin, and SNAP-25, which mediate vesicle fusion.
* **Adaptins:** AP-2 and clathrin, which play a role in endocytosis.
* **Other proteins:** Dynamin, which is involved in vesicle scission; and actin, which provides structural support.
* **Function:** The postsynaptic recycling endosome serves as a hub for the retrieval and recycling of synaptic vesicle components, including neurotransmitters, transmembrane proteins, and lipids.

**Recycling process:**
1. After the release of neurotransmitter from synaptic vesicles at the synapse, the empty vesicles are retrieved via endocytosis.
2. These endocytosed vesicles fuse with the recycling endosome.
3. Within the recycling endosome, the vesicle contents are sorted and recycled.
4. The recycling endosome then buds off new vesicles, filled with neurotransmitter and other essential components, which are transported back to the active zone for release.

**Significance:**
The postsynaptic recycling endosome is critical for maintaining the rapid and efficient neurotransmission at synapses. Dysregulation of this compartment can lead to impaired synaptic plasticity and neurotransmission, potentially contributing to neurological disorders.'
"

Proteins (2)

Compounds (1)