Vesicular-tubular cluster
Encyclopedia
A vesicular-tubular cluster (VTC), also referred to as the ER-Golgi intermediate compartment (or ERGIC), is an organelle
in eukaryotic cells. This compartment mediates trafficking between the endoplasmic reticulum
and Golgi complex, facilitating the sorting of cargo. The compartment was first defined as the location within the cell of the mannose-binding membrane lectin
called ERGIC-53.
In mammal
ian organisms, COPII
vesicles that have budded from exit sites in the endoplasmic reticulum lose their coats and fuse to form the vesicular-tubular cluster (VTC). Retrieval (or retrograde) transport in COPI
vesicles returns many of the lost ER resident proteins back to the endoplasmic reticulum. Forward (or anterograde) transport moves the VTC contents to the cis-Golgi network, the receiving face of the Golgi complex. This process is thought to occur by one of two processes. One is known as cisternal maturation where the VTC simply matures into the cis-Golgi network. In another COPI
vesicular transport moves VTC material to the receiving face of the Golgi apparatus. A fuller explanation of the two processes is described (see Golgi complex). Evidence exists for both processes and it may be that both occur simultaneously in cells.
Organelle
In cell biology, an organelle is a specialized subunit within a cell that has a specific function, and is usually separately enclosed within its own lipid bilayer....
in eukaryotic cells. This compartment mediates trafficking between the endoplasmic reticulum
Endoplasmic reticulum
The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that forms an interconnected network of tubules, vesicles, and cisternae...
and Golgi complex, facilitating the sorting of cargo. The compartment was first defined as the location within the cell of the mannose-binding membrane lectin
Lectin
Lectins are sugar-binding proteins that are highly specific for their sugar moieties. They play a role in biological recognition phenomena involving cells and proteins. For example, some viruses use lectins to attach themselves to the cells of the host organism during infection...
called ERGIC-53.
In mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
ian organisms, COPII
COPII
COPII is a type of vesicle coat protein that transports proteins from the rough endoplasmic reticulum to the Golgi apparatus. This is termed anterograde transport. The name "COPII" refers to the specific coat protein complex that initiates the budding process...
vesicles that have budded from exit sites in the endoplasmic reticulum lose their coats and fuse to form the vesicular-tubular cluster (VTC). Retrieval (or retrograde) transport in COPI
COPI
COPI is a protein complex that coats vesicles transporting proteins from the cis end of the Golgi complex back to the rough endoplasmic reticulum , where they were originally synthesized and between golgi compartments. This type of transport is termed as retrograde transport...
vesicles returns many of the lost ER resident proteins back to the endoplasmic reticulum. Forward (or anterograde) transport moves the VTC contents to the cis-Golgi network, the receiving face of the Golgi complex. This process is thought to occur by one of two processes. One is known as cisternal maturation where the VTC simply matures into the cis-Golgi network. In another COPI
COPI
COPI is a protein complex that coats vesicles transporting proteins from the cis end of the Golgi complex back to the rough endoplasmic reticulum , where they were originally synthesized and between golgi compartments. This type of transport is termed as retrograde transport...
vesicular transport moves VTC material to the receiving face of the Golgi apparatus. A fuller explanation of the two processes is described (see Golgi complex). Evidence exists for both processes and it may be that both occur simultaneously in cells.