The control of cell growth was once thought to be passive when there were cellular building blocks in nutrients; a cell would grow and ultimately divide. But I’m joined today by Dr. Michael Hall (Figure 1) from the University of Basel in Switzerland who upended this simple assumption and, instead, elucidated the very complex and elegant signaling pathways that result in cell growth. At the core is TOR, the target of rapamycin. Watch the full interview at www. jci. org/videos/cgms to find out how many times a day he says “rapamycin” and whether or not he’s ever been to Rapa Nui. JCI: You have international roots. Hall: I have a rather complicated life history. I was born in Puerto Rico, and my family moved when I was three to South America, to Peru, where we lived for several years, and then eventually we moved to Venezuela, where we lived several more years. I left South America as a teenager to go to boarding school in the United States. My father was an executive for a multinational company. My mother had studied Spanish in college and had a degree in Spanish. They liked the culture of Latin America, and they decided to make their lives there. JCI: Where did an interest in science come from?

Hall: It was a very gradual process for me. What set the foundation was my parents instilling in me the importance of knowledge. I think that came through most clearly when they sent me away to boarding school when I was 13. That was a huge sacrifice for my mother because it was a breaking apart of the family, but she understood the importance of education. Had I stayed in South America, I would not have received a very good education. Boarding school in Massachusetts was one of the defining experiences in my life. It was a huge cultural shock. I had a carefree life in South America; everything was open and free. Then I went to this boarding school that was at the other end of the spectrum, very disciplined, very rigid, and the weather was not the same, I had to wear a coat and tie every day instead of a