InterPro domain: IPR018450

This entry includes a group of mitochondrial proteins, including reactive oxygen species modulator 1 (Romo1) from animals and Mgr2 from fungi.

Budding yeast Mgr2 is a subunit of the TIM23 translocase complex, which translocates preproteins into and across the membrane and associates with the matrix-localized import motor. It is required for binding of Tim21 to TIM23(CORE). Mrg2 is essential for cell growth at elevated temperature and for efficient protein import [ 1 ].

Romo1 is responsible for increasing the level of ROS in cells. In various cancer cell lines with elevated levels of ROS there is also an increased abundance of Romo1 [ 2 ]. Increased Romo1 expression can have a number of other affects including: inducing premature senescence of cultured human fibroblasts [ 3 , 4 ] and increased resistance to 5-fluorouracil [ 5 ].

1. Mgr2 promotes coupling of the mitochondrial presequence translocase to partner complexes. J. Cell Biol. 197, 595-604
2. A novel protein, Romo1, induces ROS production in the mitochondria. Biochem. Biophys. Res. Commun. 347, 649-55
3. Replicative senescence induced by Romo1-derived reactive oxygen species. J. Biol. Chem. 283, 33763-71
4. A critical role for Romo1-derived ROS in cell proliferation. Biochem. Biophys. Res. Commun. 369, 672-8
5. Drug resistance to 5-FU linked to reactive oxygen species modulator 1. Biochem. Biophys. Res. Commun. 359, 304-10