JUNE 2020 Michael Rosbash, M.D. NOT FOR PUBLIC DISTRIBUTION

Mishka Richards My name is Mishka Richards from Indiana and South Carolina and it is my honor to introduce Dr. Michael Rosbash. Dr. Rosbash’s research focuses on the metabolism and processing of mRNA, the molecular link between DNA and protein. His research ultimately led to him receiving the Nobel Prize in Physiology or Medicine. He and his colleagues identified a gene that encodes a protein that accumulates during the night, which is degraded during the day. They also identified additional proteins that form parts of a self-regulating biological clockwork, applicable to a range of animals and plants. Dr. Rosbash, welcome to the Congress of Future Medical Leaders.

Dr. Rosbash Thank you very much, Mishka. It's a pleasure to be here. And so I don't forget I want to not only thank Mishka and Richard for that gracious introduction and accurate, I might add, but also to Angelina Bucci, who's going to lead the question and answer session that follows. So, I'm going to begin this talk with a few personal thoughts that will give you a little bit of insight into my history. And I think if there's an overarching summary of these few minutes, it's really that there are many ways to arrive at your goal. There's not just one formula. So where should we begin? Like, the White Rabbit said in Alice In Wonderland, I think the place to begin is at the beginning, and then you continue until you come to the end, and then you stop. That's my personal journey, and it will be yours as well. So I thought I'd start at the beginning and show you a picture of my father's so called Frenton Pass. This was the pass that the German authorities gave to Jewish citizens when they revoked their citizenship. And that's shown on the left. And on the right is my dad's visa to the United States, which was signed in June of 1938. And one month later, he and my mother sailed as newlyweds to the United States where I was born. So that's my cultural background, if you will.

I want to point out the fact that, you know, I then had a journey like everybody beginning with childhood, and ending with Brandeis where I am currently, where I've been for a long time. And I want to say a word about childhood. Just to put this a bit in perspective. My father died in 1954 when I was 10 years old. And so that was a real blow to be into my family and made for a rocky beginning. And in fact, there is aspects of my journey, which are far from smooth, rocky is probably a good adjective to describe them. And they've often been attributed to this blow I suffered when I was 10 years old, that is the loss of my father. And that's a reasonable hypothesis, but of course, it's not an exclusive one. And I thought you might like to see and be amused by my report card from first grade, which my mother dutifully kept. And I can't see the details here because it's a bit blurry on my screen. OFFICIAL TRANSCRIPT NATIONAL ACADEMY OF FUTURE PHYSICIANS AND MEDICAL SCIENTISTS © 2020 ALL RIGHTS RESERVED 1 JUNE 2020 But you'll notice that for some of these categories, my report was less than Sterling. It was unsatisfactory for a couple of those behavioral criteria. And of course, this is first grade when I was six years old. And my dad died when I was 10. So I think this is a strong indication that some of the rougher parts of my personality, some of the difficulties I had along the way, were not solely due to my father's death, because they really showed up before I ever, years before that occurred.

So the importance of data to try to distinguish between hypotheses. And then let me say a word about the big middle features here on this journey. My undergraduate years at Caltech, a year I spent in Paris, between undergraduate school at Caltech and graduate school at MIT. And then four to five years I spent at MIT as a PhD student. So those two universities, Caltech and MIT have a distinguishing feature that is, they're really meritocracies. They care about what you do, and not where you come from. And in my particular case, they are quite liberal about not paying attention to some behavioral idiosyncrasies that might count against one, in other locations. So I'm very grateful to those places for having ignored what could have been real liabilities in other institutions. And I'm really very thankful to that year in Paris that I managed to have for giving me an appreciation to the wider world. Some of the comments about Vietnam by the previous speaker reminded me of the warm place in my heart that those very formative year at the age of 21 holds for me in Paris. So let me end by simply saying that I ended up at Brandeis as an assistant professor. And it was really an accident that I went there. I didn't know about any of these things. And it was really at Brandeis that I met Jeff Hall, who became my partner for 20 years as a collaborator. Jeff was one of the three co recipients, one of my two co recipients for this Nobel Prize. And it was through Jeff, that I learned not only about genetics, but also about circadian rhythms. I was a nucleic acid biochemist, knew nothing about that sort of thing. And it's really through him that I learned it.

So let me begin and tell you a little bit about circadian biology. So it is really a biological phenomena that arose in response to this inexorable rotation of the Earth, the light dark cycle that accompanies all of life. And it turns out that many, most organisms have a circadian clock, and arguably the oldest one is in cyanobacteria, which is responsible for oxygenating the atmosphere more than 2 billion years ago, a photosynthetic organism as you can appreciate from the green color. And circadian rhythms really have four defining characteristics. The rhythms are not exactly 24 hours, they're about 24 hours, but they become 24 hours by, in training or becoming in sync by the light dark cycle. And the purpose of this is really anticipation. Knowing what is going to happen, the early bird gets the worm, and the early worm avoids being eaten by the bird. And there's some evidence that internal biochemistry, internal coherence is also regulated by circadian rhythms. And I want to point out that locomotor activity is really a striking phenotype for circadian biology. That is the active phase indicated in this hamster running wheel picture, by those little ticks. And you can see that the hamster is keeping a not exactly 24 hour period in constant darkness.

OFFICIAL TRANSCRIPT NATIONAL ACADEMY OF FUTURE PHYSICIANS AND MEDICAL SCIENTISTS © 2020 ALL RIGHTS RESERVED 2 JUNE 2020 It's shorter than 24 hours, but in a light dark cycle. It's exactly bang on 24 hours. And the mantra of genetics is really like real estate, which is location, location and location. And for genetics is phenotype, phenotype, phenotype. So locomotor activity is a fantastic phenotype. And this locomotor activity phenotype was recapitulated for Drosophila by Konopka and Benzer, who assayed fruit flies running back and forth in a little tube as shown here with some food at the bottom and a stopper on the top. And this genetic screen that Konopka and Benzer did in the in the late 60s, published in 70, early 70s, managed to identify three mutants of fruit flies, which had altered circadian rhythms. And those three mutants, an arrhythmic mutant, a short period mutant, and a long period mutant, were all alleles of a single gene called period. And it was that gene and the cloning of that gene as Misha described, which really was the beginning of our circadian journey and I want to point out to you, and you'll notice that about why genetics.

So I want to emphasize here that this is not to distinguish between you and me, or to ask, how are we different, and is that genetic. It's really as an entree into a mysterious process. There's no way to get at circadian biology, except through genetics. And that's really what we did. And so that really led to this conserved negative feedback loop at the level of transcription, where transcription factors drive the synthesis of their own negative regulators. And those negative regulators feedback, and turn off their own synthesis. And that turns out to be a conserved process, not just the process itself. But the actual genes are conserved between flies and mice, which is what gave this whole process its importance. And so I want to point out some future challenges that someone like you might keep in mind if you become interested or maintain an interest in circadian biology.

First of all, on the basic science front, we really don't understand why the cycle is about 24 hours. Why isn't it 17? Why isn't it 28, we really don't know what the rate limiting steps are. And that's because of a paucity of biochemistry, the system has not been mammalian system, or the eukaryotic system has not been recapitulated in vitro. And that's something which really has to be done in order to understand the nuts and bolts of the timing mechanism. Now, a second challenge is really to apply what we've learned about circadian biology to human health. And listed here are just some of the things indications we have, that the clock and to some extent its regulation or its misregulation in humans plays a very important role in human health in all the various facets that are listed there, and more. And I'll give you, and we can ask the question, why are there so many phenomena which are under circadian regulation. Or to put it another way, why is so much physiology under circadian control. And the reason why that is the case is because this feedback loop, the circadian feedback loop regulates not only the small number of genes which are involved in this loop, but also a large number of secondary and even tertiary genes, which then give rise to all of the various phenomena which impact physiology, impact human physiology. And so that's one dimension of the explanation, that is within each cell, there's a lot of messenger RNAs under clock control. But then the second dimension is the fact that every cell, and every tissue in the body illustrated here by this mouse, has this core clock operating within it. OFFICIAL TRANSCRIPT NATIONAL ACADEMY OF FUTURE PHYSICIANS AND MEDICAL SCIENTISTS © 2020 ALL RIGHTS RESERVED 3 JUNE 2020 And therefore, all, there are many messenger RNAs within each of those cells which are oscillating. So those are really the two reasons why so much of this is under circadian control. And that's the explanation for why so much of physiology is suspect. And I should just say that I can't read this. Oh yes. And I want to give you an illustration of one specific piece of physiology under circadian control, which is metabolic disorders or metabolic changes. And this is really best illustrated by a paper done, spearheaded by the laboratory of my circadian colleagues, Sasha Panda at the Salk Institute.

And what Sasha Panda showed was that, if you feed a mouse with a circadian program so that it is fed for only a certain part of the day, and then not fed for another part of the day, that the mouse is resistant to a high fat diet, and it doesn't become obese. And this is despite the fact that that mouse consumes exactly the same number of calories as a mouse that's fed all around the clock. And also, there's no change in respiration. So, the moral of the story is it's not just how much you eat, and it's not just what you eat, but it's actually when you eat, it turns out to be important. And the third challenge for the future, now back to basic science, is to try to understand why we sleep, who is keeping track of how much sleep we've had, and how much sleep we need. And this is called the homeostatic regulatory system of sleep. Nobody understands it. And of course, it's really at the base of the conserve nature of sleep. And by conserved, what I mean is the fact that sleep is something universal from flies to humans, just like circadian biology is. And it's possible that the fruit fly will contribute to our understanding of sleep, this future challenge just as it has made a really massive contribution to our understanding of circadian biology. And so, this is a segue to the last section where I'm going to once again, try and wax a bit philosophical on a number of points.

First of all, as this humorous cartoon indicates, only three humans can share a Nobel Prize. But we thought that the fruit fly is so important to our work and to biology in general, that perhaps they could make an exception and include that organism in the prize going forward. And of course, that also pays homage to the fact that ours is the fifth Nobel prize that is based on research with fruit flies, beginning with the great pioneer T. H. Morgan for his pioneering genetic map discoveries in the early part of the 20th century. So the fruit fly has really been seminal to work into basic science. And I want to make a few general points about chance genes and necessity here. And, you can you can sort of read the slide. But the idea here is it's not really how you began, how you begin in life.

Many of us are biologists because we had a great high school teacher, no shame in that. So it doesn't matter where things begin. Secondly, I want to impress upon you the fact that genes are not destiny, but they certainly tilt the table. And just to put a personal touch on this, I tried for years to be able to dunk a basketball. I worked really hard in it, and I just couldn't do it. And that was almost certainly a genetic threshold that I just couldn't overcome. My wife has made the point to me, that, and it speaks to the third point, this relationship between chance and genes.

OFFICIAL TRANSCRIPT NATIONAL ACADEMY OF FUTURE PHYSICIANS AND MEDICAL SCIENTISTS © 2020 ALL RIGHTS RESERVED 4 JUNE 2020 That for those of you who are intelligent, and I suspect that’s many of you out there, you should appreciate the fact that that's due to your genes, and that's just good luck. That's nothing you weren't. And so emphasizing this important perspective, of luck or chance, should enhance a sense of humility. For most of the things we've done, or for many of them, it's by accident. And this should not only engender a sense of humility, but also a sense of tolerance for those who have been unable to achieve what you have. And so don't be too hard on yourself. If you don't get to the end line, it's really not your fault. Not everything is under your control. And so this brings me to a word or two about means and ends. The only thing you can really pay attention to is means, you can't control the ends. The past is gone, the future is unpredictable. So pay attention to the means in life. And this is really your journey through science and medicine, enjoy it. Realize that we really all privileged to be going to school, to be doing things, or having a job that we love. And for other professions where they're artists, they have a much harder time earning a living, a great violinist or a painter than scientists and physicians do. So we're really a very privileged subset of society. And all of us owe a debt of gratitude to those people who have been part of our past that have helped us along the way. Your parents in your case, my parents in my case, friends and colleagues. And in my particular case, and for those of you who work in a laboratory, you'll appreciate the fact that none of us build an edifice by ourselves. All of us have colleagues and coworkers, and I always try to make a point to thank my lab. If this were a different venue, I would have a very, very, very dense slide with all the people who helped me along the way, but what I currently do when I get a contemporary seminar is always make a point of thanking the students and postdocs, and technicians in my lab who have helped me along the way, and continue to do so.

And with that, I'll end. And thank you very much for your attention, and I wish you all the best of luck.

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