- THIS ARTICLE
- Full Text
- Full Text (PDF)
- Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Email this article to a friend
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Chen, X. J.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Chen, X. J.
Genetics, Vol. 167, 607-617, June 2004, Copyright © 2004
doi:10.1534/genetics.103.023655
Sal1p, a Calcium-Dependent Carrier Protein That Suppresses an Essential Cellular Function Associated With the Aac2 Isoform of ADP/ATP Translocase in Saccharomyces cerevisiae
Xin Jie Chen1
Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9148 and Research School of Biological Sciences, The Australian National University, Canberra, ACT 2601, Australia
1 Address for correspondence: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., NA5.142, Dallas, TX 75390-9148.
E-mail: xinjie.chen{at}utsouthwestern.edu
Adenine nucleotide translocase (Ant) catalyzes ADP/ATP exchange between the cytosol and the mitochondrial matrix. It is also proposed to form or regulate the mitochondrial permeability transition pore, a megachannel of high conductancy on the mitochondrial membranes. Eukaryotic genomes generally contain multiple isoforms of Ant. In this study, it is shown that the Ant isoforms are functionally differentiated in Saccharomyces cerevisiae. Although the three yeast Ant proteins can equally support respiration (the R function), Aac2p and Aac3p, but not Aac1p, have an additional physiological function essential for cell viability (the V function). The loss of V function in aac2 mutants leads to a lethal phenotype under both aerobic and anaerobic conditions. The lethality is suppressed by a strain-polymorphic locus, named SAL1 (for Suppressor of aac2 lethality). SAL1 was identified to encode an evolutionarily conserved protein of the mitochondrial carrier family. Notably, the Sal1 protein was shown to bind calcium through two EF-hand motifs located on its amino terminus. Calcium binding is essential for the suppressor activity. Finally, Sal1p is not required for oxidative phosphorylation and its overexpression does not complement the R– phenotype of aac2 mutants. On the basis of these observations, it is proposed that Aac2p and Sal1p may define two parallel pathways that transport a nucleotide substrate in an operational mode distinct from ADP/ATP exchange.
This article has been cited by other articles:
 |
|
 |
|
  M. K. Dienhart and R. A. Stuart The Yeast Aac2 Protein Exists in Physical Association with the Cytochrome bc1-COX Supercomplex and the TIM23 Machinery Mol. Biol. Cell, September 1, 2008; 19(9): 3934 - 3943. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. P. Smith and P. E. Thorsness The Molecular Basis for Relative Physiological Functionality of the ADP/ATP Carrier Isoforms in Saccharomyces cerevisiae Genetics, July 1, 2008; 179(3): 1285 - 1299. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Satrustegui, B. Pardo, and A. del Arco Mitochondrial Transporters as Novel Targets for Intracellular Calcium Signaling Physiol Rev, January 1, 2007; 87(1): 29 - 67. [Abstract] [Full Text] [PDF]
|
|