Table 1.

Description of different levels of stepwise MAS reconstitution (relates to Figs. 3–8)

	Stepwise MAS reconstitution	Constituents	Metabolic consequences and use of inhibitors/effectors
Mitochondria	Mode 1 (minimal MAS)	Glutamate-malate, ADP	Glutamate-malate-driven respiration (state 3) controlled by extramitochondrial Ca2+ through activation of Aralar.
	Mode 2 (incomplete MAS)	Glutamate-malate, ADP + α-oxoglutarate, aspartate, lactate, NADH	MAS substrates present but in the absence of MAS enzymes; this mode lacks the MAS-driven generation of pyruvate and is thus not yet fully functional but extramitochondrial Ca2+-sensitive.
	Mode 3 (complete reconstituted MAS)	Glutamate-malate, ADP, α-oxoglutarate, aspartate, lactate, NADH + LDH, GOT, and MDH	MAS substrates and enzymes added, thus allowing a continuous generation of pyruvate at the maximum rate, depending on extramitochondrial Ca2+ level. Cin inhibits mitochondrial pyruvate uptake and AOA inhibits MAS enzyme GOT (both inducing pyruvate starvation).
Cells	Mode 4 (complete endogenous MAS)	All constituents endogenously present as described for MAS mode 3 but in their natural stoichiometries	Endogenous MAS activity controlled by cytosolic Ca2+. AOA inhibits MAS enzyme GOT and BAPTA-AM chelates Ca2+ to restrict MAS activation (both inducing a state of pyruvate starvation).
Heart	Mode 5 (complete endogenous MAS)	All constituents endogenously present as described for MAS mode 3 but in their natural stoichiometries	Endogenous MAS activity controlled by cytosolic Ca2+; AOA inhibits MAS enzyme GOT (inducing a state of pyruvate starvation).