Recombinant Human ADP/ATP translocase 4 (SLC25A31), Truncated

Uniprot Id

Q9H0C2

Target Species

Human

Target Name

SLC25A31

Target Full Name

ADP/ATP translocase 4

Target Function

ADP:ATP antiporter that mediates import of ADP into the mitochondrial matrix for ATP synthesis, and export of ATP out to fuel the cell. Cycles between the cytoplasmic-open state (c-state) and the matrix-open state (m-state): operates by the alternating access mechanism with a single substrate-binding site intermittently exposed to either the cytosolic (c-state) or matrix (m-state) side of the inner mitochondrial membrane. Specifically required during spermatogenesis, probably to mediate ADP:ATP exchange in spermatocytes. Large ATP supplies from mitochondria may be critical for normal progression of spermatogenesis during early stages of meiotic prophase I, including DNA double-strand break repair and chromosomal synapsis. In addition to its ADP:ATP antiporter activity, also involved in mitochondrial uncoupling and mitochondrial permeability transition pore (mPTP) activity. Plays a role in mitochondrial uncoupling by acting as a proton transporter: proton transport uncouples the proton flows via the electron transport chain and ATP synthase to reduce the efficiency of ATP production and cause mitochondrial thermogenesis. Proton transporter activity is inhibited by ADP:ATP antiporter activity, suggesting that SLC25A31/ANT4 acts as a master regulator of mitochondrial energy output by maintaining a delicate balance between ATP production (ADP:ATP antiporter activity) and thermogenesis (proton transporter activity). Proton transporter activity requires free fatty acids as cofactor, but does not transport it. Also plays a key role in mPTP opening, a non-specific pore that enables free passage of the mitochondrial membranes to solutes of up to 1.5 kDa, and which contributes to cell death. It is however unclear if SLC25A31/ANT4 constitutes a pore-forming component of mPTP or regulates it.

Target Subcellular Location

Mitochondrion inner membrane; Multi-pass membrane protein. Membrane; Multi-pass membrane protein. Cell projection, cilium, flagellum membrane; Multi-pass membrane protein.

Target Protein Families

Mitochondrial carrier (TC 2.A.29) family

Target Tissue Specificity

Expressed in brain, liver, sperm and testis. In testis, expressed at higher level in spermatocytes, while it is expressed at lower level in spermatogonial cells. Expressed in erythrocytes (at protein level).

Target Synonyms

SLC25A31; AAC4; ANT4; SFEC; ADP/ATP translocase 4; ADP,ATP carrier protein 4; Adenine nucleotide translocator 4; ANT 4; Solute carrier family 25 member 31; Sperm flagellar energy carrier protein

Target Background

The protein encoded by this gene is a member of the ADP/ATP carrier family of proteins that exchange cytosolic ADP for matrix ATP in the mitochondria. Cells over-expressing this gene have been shown to display an anti-apoptotic phenotype. This protein is also thought to play a role in spermatogenesis, where it is believed to associate with a part of the flagellar cytoskeleton and with glycolytic enzymes. Male mice with mutations in the mouse ortholog of this gene are sterile and spermatocytes display an early meiotic arrest phenotype. Alternative splicing results in multiple transcript variants encoding different isoforms.