MCU functions with MICU1, an essential gatekeeper component of calcium-channel transport, to facilitate Ca2+ uptake into the mitochondrion [1,2,3].

1: A forty-kilodalton protein of the inner membrane is the mitochondrial calcium uniporter. De Stefani D, Raffaello A, Teardo E, Szabo I, Rizzuto R; Nature. 2011;476:336-340. PMID:21685888

2: After half a century mitochondrial calcium in- and efflux machineries reveal themselves. Drago I, Pizzo P, Pozzan T; EMBO J. 2011;30:4119-4125. PMID:21934651

3: EMRE is an essential component of the mitochondrial calcium uniporter complex. Sancak Y, Markhard AL, Kitami T, Kovacs-Bogdan E, Kamer KJ, Udeshi ND, Carr SA, Chaudhuri D, Clapham DE, Li AA, Calvo SE, Goldberger O, Mootha VK; Science. 2013;342:1379-1382. PMID:24231807

4: MCUR1 is an essential component of mitochondrial Ca2+ uptake that regulates cellular metabolism. Mallilankaraman K, Cardenas C, Doonan PJ, Chandramoorthy HC, Irrinki KM, Golenar T, Csordas G, Madireddi P, Yang J, Muller M, Miller R, Kolesar JE, Molgo J, Kaufman B, Hajnoczky G, Foskett JK, Madesh M; Nat Cell Biol. 2012;14:1336-1343 PMID:23178883