Mitsuo Tagaya received his Ph.D. at Osaka University in 1985 by revealing the catalytic mechanisms of glycogen phosphorylase and glycogen synthase. He developed new affinity labeling reagents comprising pyridoxal phosphate for the identification of nucleotide-binding sites. He then worked with James E. Rothman, a Nobel Prize laureate in Physiology or Medicine 2013, at Princeton, where he began organelle research. After returning to Japan, he became associate professor in a newly established department, the School of Life Sciences, at Tokyo University of Pharmacy and Life Sciences in 1994, and became professor in 1997. His interest has focused on the mechanism of the organization of the microdomains of the endoplasmic reticulum.Thomas Simmen studied biochemistry at the University of Basel. Following a Ph.D. in Lausanne, where he unraveled the functions of the AP-4 adaptor complex in basolateral sorting, he did two postdoctoral fellowships, one with Roberto Sitia in Milan, the other with Gary Thomas in Portland OR. This period introduced him to the connections between the endoplasmic reticulum (ER) and mitochondria, because he worked on Ero1α, a regulator of ER-mitochondria calcium signaling, and on PACS-2, the first identified factor required for the tethering of the ER to mitochondria. Starting in 2005, Thomas Simmen became a faculty member of the Department of Cell Biology at the University of Alberta (Edmonton, Canada). The Simmen laboratory detected ER protein-folding enzymes such as calnexin and TMX1 and the small GTPase Rab32 as factors controlling the function of ER-mitochondria contacts and the mitochondria-associated membrane (MAM).