@article {825511, title = {Genome-wide RNAi screen identifies Letm1 as a mitochondrial Ca2+/H+ antiporter.}, journal = {Science}, volume = {326}, year = {2009}, month = {2009 Oct 2}, pages = {144-7}, abstract = {

Mitochondria are integral components of cellular calcium (Ca2+) signaling. Calcium stimulates mitochondrial adenosine 5{\textquoteright}-triphosphate production, but can also initiate apoptosis. In turn, cytoplasmic Ca2+ concentrations are regulated by mitochondria. Although several transporter and ion-channel mechanisms have been measured in mitochondria, the molecules that govern Ca2+ movement across the inner mitochondrial membrane are unknown. We searched for genes that regulate mitochondrial Ca2+ and H+ concentrations using a genome-wide Drosophila RNA interference (RNAi) screen. The mammalian homolog of one Drosophila gene identified in the screen, Letm1, was found to specifically mediate coupled Ca2+/H+ exchange. RNAi knockdown, overexpression, and liposome reconstitution of the purified Letm1 protein demonstrate that Letm1 is a mitochondrial Ca2+/H+ antiporter.

}, keywords = {Animals, Antiporters, calcium, Calcium-Binding Proteins, Cation Transport Proteins, Cell Line, drosophila melanogaster, Drosophila Proteins, Genome, Human, Genome, Insect, HeLa Cells, Humans, Hydrogen, Hydrogen-Ion Concentration, Ion Transport, Membrane Potential, Mitochondrial, Membrane Proteins, mitochondria, Mitochondrial Membranes, Mitochondrial Proteins, Proteolipids, RNA Interference}, issn = {1095-9203}, doi = {10.1126/science.1175145}, author = {Jiang, Dawei and Zhao, Linlin and Clapham, David E} }