long-chain fatty acid transport

Definition

Target type: biologicalprocess

The directed movement of a long-chain fatty acid into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. A long-chain fatty acid has an aliphatic tail containing 13 to 22 carbons. [GOC:ai]

Long-chain fatty acid transport is a complex process involving multiple steps and cellular components. It begins with the uptake of fatty acids from the bloodstream, primarily through the liver and adipose tissue. The fatty acids then need to be transported within the cell and eventually across cellular membranes.

**1. Uptake:**

- Fatty acids in the bloodstream are bound to albumin, a protein that acts as a carrier molecule.
- Cells take up fatty acids through a process called facilitated diffusion, which utilizes specific membrane transport proteins.
- One crucial protein is the fatty acid transporter protein (FAT/CD36), which binds to albumin-bound fatty acids and facilitates their passage across the cell membrane.

**2. Intracellular Transport:**

- Once inside the cell, fatty acids are bound to fatty acid-binding proteins (FABPs), such as intracellular fatty acid-binding protein (FABP4/aP2).
- FABPs help solubilize fatty acids and facilitate their transport to different cellular compartments, including mitochondria for energy production, and the endoplasmic reticulum for storage or further processing.

**3. Mitochondrial Transport:**

- Fatty acids destined for energy production need to be transported into the mitochondria, the powerhouse of the cell.
- This process is mediated by a series of enzymes, including carnitine palmitoyltransferase 1 (CPT1) and CPT2.
- CPT1 converts fatty acids to acylcarnitines, which can then cross the mitochondrial membrane.
- CPT2 within the mitochondria converts acylcarnitines back to fatty acids, allowing them to enter the beta-oxidation pathway.

**4. Storage and Transport to Other Tissues:**

- Fatty acids can be stored as triglycerides in adipose tissue.
- Triglycerides can be broken down back into fatty acids and glycerol when needed, then released into the bloodstream for transport to other tissues.
- The lipoprotein lipase (LPL) enzyme hydrolyzes triglycerides in the bloodstream, releasing free fatty acids for uptake by various tissues.

**5. Cellular Export:**

- Fatty acids can also be transported out of cells for various purposes.
- This process involves specific efflux transporters like the ATP-binding cassette transporter A1 (ABCA1), which exports fatty acids to the extracellular environment.

**Overall, long-chain fatty acid transport is a finely regulated process that ensures the proper delivery and utilization of these essential molecules for energy production, storage, and other cellular functions.**'
"

Proteins (7)

Compounds (152)