post-Golgi vesicle-mediated transport

Definition

Target type: biologicalprocess

The directed movement of substances from the Golgi to other parts of the cell, including organelles and the plasma membrane, mediated by small transport vesicles. [GOC:ai, GOC:mah]

Post-Golgi vesicle-mediated transport is a fundamental process in eukaryotic cells responsible for the delivery of newly synthesized proteins and lipids from the Golgi apparatus to their final destinations throughout the cell. This complex and highly regulated pathway involves the formation of transport vesicles, their budding from the Golgi, movement along cytoskeletal tracks, docking at target membranes, and fusion with these membranes to release their cargo.

1. **Vesicle Formation**: The Golgi apparatus serves as a sorting station for newly synthesized proteins and lipids. Proteins destined for different cellular compartments are packaged into distinct vesicles at specific Golgi compartments. This packaging involves the recruitment of cargo receptors that bind to specific cargo proteins, as well as the assembly of coat proteins around the budding vesicle. The coat proteins help shape the vesicle, select cargo, and ensure proper targeting. Common coat protein complexes involved in post-Golgi transport include COPI, COPII, and clathrin.

2. **Budding and Vesicle Movement**: Once the vesicle is formed, it buds off from the Golgi membrane. This process often involves GTPases (e.g., ARF and Rab proteins) that regulate the assembly and disassembly of coat proteins. After budding, the vesicle is transported along cytoskeletal tracks. Microtubules and their associated motor proteins (e.g., dynein and kinesin) play a key role in long-distance movement, while actin filaments and their motor proteins (e.g., myosin) are involved in shorter range movements.

3. **Tethering and Docking**: The vesicle must reach its correct target membrane. This requires specific recognition and tethering events. Tethering factors, often large protein complexes, bind to the vesicle and to the target membrane, bringing the two membranes into close proximity. This is followed by docking, where the vesicle interacts with specific proteins on the target membrane (e.g., SNARE proteins).

4. **Fusion and Cargo Delivery**: Once docked, the vesicle membrane fuses with the target membrane, releasing the cargo into the target compartment. Fusion is mediated by a complex interaction of SNARE proteins on the vesicle and target membrane, which brings the two membranes together and promotes their merging.

**Overall, post-Golgi vesicle-mediated transport is a critical process for cellular function and is essential for maintaining cellular organization, signaling, and response to the environment.**'
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Proteins (2)

Compounds (1)