Leucine zipper EF hand-containing transmembrane protein 1 (Letm1) and uncoupling proteins 2 and 3 (UCP2/3) contribute to two distinct mitochondrial Ca2+ uptake pathways.

ABSTRACT: Cytosolic Ca(2+) signals are transferred into mitochondria over a huge concentration range. In our recent work we described uncoupling proteins 2 and 3 (UCP2/3) to be fundamental for mitochondrial uptake of high Ca(2+) domains in mitochondria-ER junctions. On the other hand, the leucine zipper EF hand-containing transmembrane protein 1 (Letm1) was identified as a mitochondrial Ca(2+)/H(+) antiporter that achieved mitochondrial Ca(2+) sequestration at small Ca(2+) increases. Thus, the contributions of Letm1 and UCP2/3 to mitochondrial Ca(2+) uptake were compared in endothelial cells. Knock-down of Letm1 did not affect the UCP2/3-dependent mitochondrial uptake of intracellularly released Ca(2+) but strongly diminished the transfer of entering Ca(2+) into mitochondria, subsequently, resulting

SUBMITTER: Waldeck-Weiermair M 

PROVIDER: S-EPMC3151087 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature