Adenine nucleotide translocase

Eipi (Wheelock etal., 1991) Eipil (Huang and Komuniecki, 1997) E3BP, E3-binding protein (p45) E3 ER, enoyl CoA reductase (Duran etal. 1993, 1998) AAT, adenine nucleotide translocase a-tubulin. UE, unembryonated egg L1, first-stage larva L2, second-stage larva L3, third-stage larva M, adult muscle ... 

There are several hypotheses for a specific mechanism by which ONOO- can control the open state of the PTPC. Briefly the PTPC is regulated by primary constituents of the pore, including the inner membrane adenine nucleotide translocase (ANT) and the outer membrane protein voltage-dependent anion channel (VDAC or porin). The VDAC-ANT complex can bind to signaling proteins that modulate permeability transition, such as pro-apoptotic Bax (which opens the pore) and anti-apoptotic Bcl-2... 

It is well recognized that activity of many mitochondrial enzymes is modulated by the mitochondrial acidic phospholipid cardiolipin. Adenine nucleotide translocase (ANT) of bovine heart mitochondria is known to be tightly associated with six molecules of cardiolipin (Beyer and Klingenberg, 1985), and cardiolipin is absolutely required for the ANT activity (Hoffmann et al, 1994). ADP control of the carrier transition was gradually lost after phospholipase treatment and the ADP conttol could be fully restored through the addition of cardiolipin (Beyer and Nuscher, 1996). Cardiolipin-mediated activation of cytochrome c oxidase (Abramovitch et al, 1990) and... 

Crompton, M., Virji, S., and Ward, J. M., 1998, CyclophUin-D binds strongly to complexes of the voltage-dependent anion channel and the adenine nucleotide translocase to form the permeabihty transition poie. EurJ Biochem 258 729-735. 

Figure 9.19 Adenine nucleotide translocase and phosphate transfer into the matrix. Phosphate is transported into the mitochondria with protons in a symport transport system. The adenine nucleotide translocase transports ADP into and ATP out of the mitochondria, i.e. it is electrogenic. The charge is neutralised by H movement into the matrix from the proton motive force which utilises about 25% of the energy in the proton motive force.

An increase in the rate of cross-bridge cychng increases force of contraction of muscle, which decreases the cytosolic concentration of ATP and increases that of ADP. This results, via the adenine nucleotide translocase, in a similar change in direction of ATP and ADP concentrations within the mitochondrial matrix (i.e. a decrease in the ATP/ADP concentration ratio). 

The changes in the cytosolic ADP and ATP concentrations increase the mitochondrial matrix concentration of ADP and decrease that of ATP, via the adenine nucleotide translocase, which stimulates the flux of electrons along the transfer chain. 

ACETATE KINASE ACETYL-CoA CARBOXYLASE ACETYL-CoA SYNTHETASE N-ACETYLCLUCOSAMINE KINASE ACTIN ATPase ACTOMYOSIN ATPase N-ACYLMANNOSAMINE KINASE ADENINE NUCLEOTIDE TRANSLOCASE ADENOSINE KINASE ADENYLATE KINASE (MYOKINASE) ADENYLYLSULFATE KINASE d-ALANINE-d-ALANINE LIGASE... 

ADENINE NUCLEOTIDE TRANSLOCASE ATROPISOMERS ATROXASE Attachment,... 

Inhibition of ATP-ADP exchange Atractyloside Inhibits adenine nucleotide translocase... 

The adenine nucleotide translocase, integral to the inner membrane, binds ADP3 - in the intermembrane space and transports it into the matrix in exchange for an ATP4 molecule simultaneously transported outward (see Fig. 13-1 for the ionic forms of ATP and ADP). Because this antiporter moves four negative charges out for every three moved in, its activity is favored by the... 

Santamaria M, Lanave C, Saccone C (2004) The evolution of the adenine nucleotide translocase family. Gene 333 51-59... 

Figure 17.3. Permeability transition pore (PTP). The PTP consists of voltage-dependent anion channel (VDAC), adenine nucleotide translocase (ANT) and several associated molecules including cyclophilin D (CypD) and peripheral benzodiazepine receptor (PBR). IMM, inner mitochondrial membrane OMM, outer mitochondrial membrane CytC, cytochrome c.

Y3. Yan, L. J., and Sohal, R. S., Mitochondrial adenine nucleotide translocase is modified oxidatively during aging. Proc. Natl. Acad. Sci. USA 95, 12896-12901 (1998). 

Figure 7.4 Cartoon of transport reaction catalyzed by adenine nucleotide translocase (ANT). ATP4- in the mitochondrial matrix is exchanged for ADP3- in intermembrane space between the outer and inner mitochondrial membranes.

As discussed in Section 7.2.2, ATP is delivered to the intermembrane space via the adenine nucleotide translocase (ANT) enzyme. The reference transport reaction is... 

The mitochondrial permeability transition (MPT) is the loss of the inner mitochondrial membrane impermeability to solutes caused by opening of the MPT pore (MPTP). In turn, this action results in a loss of mitochondrial function and provides a common mechanism implicated in activation of mi-tophagy/autophagy, apoptosis, and necrosis in different cell systems. Although the composition of MPTP is not fully settled, multiple studies suggest involvement of adenine nucleotide translocase (ANT) in the inner mitochondrial membrane, voltage-dependent anion channel (VDAC or porin) in the outer membrane, and cyclophilin D (CypD) in the matrix. 

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