Tricarboxylate transport protein, mitochondrial

Tricarboxylate Transport Protein, Mitochondrial

The tricarboxylate transport protein, mitochondrial is a crucial component of the mitochondrial membrane system, responsible for the transport of tricarboxylate compounds across the inner mitochondrial membrane. This protein plays a significant role in the citrate cycle (also known as the Krebs cycle), which is essential for cellular energy production.

Structure

The tricarboxylate transport protein is an integral membrane protein that spans the inner mitochondrial membrane. It is part of the mitochondrial carrier family, which is characterized by a conserved sequence motif and a similar structural fold. The protein typically consists of three repeated domains, each containing two transmembrane alpha-helices connected by a loop. This arrangement forms a channel through which tricarboxylates can be transported.

Function

The primary function of the tricarboxylate transport protein is to facilitate the exchange of tricarboxylate compounds, such as citrate, across the inner mitochondrial membrane. This transport is crucial for maintaining the balance of metabolites between the mitochondrial matrix and the cytosol. Citrate, for example, is exported from the mitochondria to the cytosol where it can be used in fatty acid synthesis and other biosynthetic pathways.

Mechanism

The transport mechanism of the tricarboxylate transport protein involves a conformational change that allows the binding and release of tricarboxylate molecules. This process is driven by the concentration gradient of the substrates and is often coupled with the transport of other ions or molecules to maintain charge balance across the membrane.

Clinical Significance

Mutations or dysfunctions in the tricarboxylate transport protein can lead to metabolic disorders. These conditions can affect energy production and lead to symptoms associated with mitochondrial diseases. Understanding the function and regulation of this protein is important for developing therapeutic strategies for such disorders.

Images

Structure of the bovine mitochondrial ADP/ATP carrier.

Another view of the bovine mitochondrial ADP/ATP carrier.

Detailed structure of the bovine mitochondrial ADP/ATP carrier.

Related Pages

• Mitochondrial carrier family
• Citrate cycle
• Mitochondrial membrane
• Metabolic disorders

References

• 

  Tricarboxylate transport protein, mitochondrial

• 

  Tricarboxylate transport protein, mitochondrial

• 

  Tricarboxylate transport protein, mitochondrial