Fig. 11. A model depicting the functional interactions between ER and mitochondria in the mouse egg. After Ca²⁺ is released from the ER into the cytosol via Ins(1,4,5)P₃ receptors it can be taken up by the mitochondria. In the mitochondrial matrix, Ca²⁺ will stimulate the Kreb’s cycle as well as the electron transport chain and the F₀/F₁ synthase that phosphorylates ADP. ATP is then transported out of the mitochondria via the activity of the adenine nucleotide translocase (ANT) and the cytosolic ATP will be consumed by the SERCA pumps to restore the resting [Ca²⁺]_c and refill the ER.