Endoplasmic reticulum-mitochondria contacts: function of the junction.

The most well-characterized organelle contact sites are those between the endoplasmic reticulum (ER) and mitochondria. Increased understanding is being gained of how ER-mitochondria contact sites are organized and which factors converge at this interface, some of which may provide a tethering function. The role of the ER-mitochondria junction in coordinating the functions of these two organelles is also becoming clearer, and it has been shown to be involved in the regulation of lipid synthesis, Ca(2+) signalling and the control of mitochondrial biogenesis and intracellular trafficking.