key term - Carnitine-acylcarnitine translocase

Definition

Carnitine-acylcarnitine translocase is a membrane protein responsible for the transport of acylcarnitine molecules across the inner mitochondrial membrane. This transport is crucial because it allows long-chain fatty acids, which are activated to acyl-CoA in the cytosol, to enter the mitochondria for beta-oxidation. The role of this translocase is essential in facilitating fatty acid degradation, making it a key player in energy metabolism.

5 Must Know Facts For Your Next Test

1. Carnitine-acylcarnitine translocase operates by exchanging acylcarnitines for free carnitine across the mitochondrial inner membrane.
2. This translocase plays a critical role in preventing the accumulation of acylcarnitines in the cytosol, which can be toxic if allowed to build up.
3. The proper function of carnitine-acylcarnitine translocase is vital for effective fatty acid oxidation and overall energy homeostasis in cells.
4. Deficiencies or dysfunctions in this translocase can lead to metabolic disorders, particularly those related to fatty acid metabolism.
5. Carnitine itself is not synthesized in sufficient amounts by the body and must be obtained from dietary sources, making its transport into mitochondria essential.

Review Questions

• How does carnitine-acylcarnitine translocase contribute to the process of fatty acid metabolism?
  • Carnitine-acylcarnitine translocase is essential for transporting acylcarnitines into mitochondria where they undergo beta-oxidation. By facilitating the exchange of acylcarnitines with free carnitine, it ensures that long-chain fatty acids can enter the mitochondria effectively. This process not only allows for energy production from fatty acids but also helps maintain cellular health by preventing the buildup of potentially harmful metabolites in the cytosol.
• What consequences might arise from a malfunction of carnitine-acylcarnitine translocase in cellular metabolism?
  • A malfunction of carnitine-acylcarnitine translocase can lead to a buildup of acylcarnitines outside mitochondria and a deficiency of free carnitine inside them. This could result in impaired fatty acid oxidation, causing energy deficits especially during fasting or intense exercise. Over time, this could contribute to metabolic disorders, leading to symptoms like muscle weakness, hypoglycemia, and increased fat accumulation due to unutilized fatty acids.
• Evaluate how carnitine-acylcarnitine translocase might be targeted for therapeutic interventions in metabolic disorders related to fatty acid metabolism.
  • Therapeutic interventions targeting carnitine-acylcarnitine translocase could focus on enhancing its activity or correcting deficiencies associated with genetic mutations. Potential strategies may include supplementing carnitine to boost levels available for transport, or developing pharmacological agents that improve the function of this translocase. By addressing the dysfunction at this transport stage, treatments could enhance fatty acid oxidation efficiency, reduce toxic metabolite buildup, and improve energy balance in patients with metabolic disorders linked to fatty acid metabolism.

Related terms

Carnitine: A quaternary ammonium compound derived from lysine that plays a critical role in the transport of fatty acids into the mitochondria for oxidation.

Beta-oxidation: A metabolic process that breaks down fatty acids into acetyl-CoA units within the mitochondria, generating ATP and reducing equivalents.

Acyl-CoA: A thioester derived from fatty acids and coenzyme A, serving as an important molecule in lipid metabolism and energy production.