Scientist Stories: Thomas Cech, RNA as an Enzyme

Welcome to the Fall 2022 UCI School of Medicine Dean's Distinguished Lecture Series. I'm Dr. Michael Stamos, Dean of the School of Medicine here at UCI. What a great event, what a great turnout, a lot of really special guests, a lot of campus leaders, a lot of school leaders, a lot of community members, and there are some special guests I want to point out right now. If you look in the front row, what do you see? Oh my goodness, sophomores and juniors from Westminster High School, budding scientists. We love, we love your enthusiasm and interest in science. Keep at it. That's great. The Dean's Distinguished Lecture Series was designed back in 2019 to bring together influential leaders from healthcare and academia to share their insights, their experience, and anecdotal stories with our faculty, staff, students, and community members like yourselves. It was intended to be an annual series of 3 speakers. However, the pandemic kind of threw a wrench in our plans. The intention was that each year we would have one speaker chosen by our vice deans of clinical research, basic science research, and Clinical Affairs to represent advances in developments in clinical research, advances in clinical medicine, and like our speaker tonight, representing innovation in basic sciences. I'm honored to inform you that our speaker tonight is a Nobel laureate, Nobel Prize winner. I think you know that. And one of the most influential leaders in the study of RNA. His name is Thomas R. Cech, and he will share his insight, his experience, and his vision in his presentation titled "The Marvelous Molecule RNA." This was supposed to happen 3 years ago, and I'll let Tom explain that story, although many of you could probably guess, but he'll give you some nuance. But it seems to me that RNA has taken on even more importance over the last 3 years, hasn't it, right? So very timely. We ask that you hold your questions until the very end. We will have microphones available so everyone can share in a Q&A. Also, please be aware that this lecture is being recorded and live-streamed. The full recording will be available to you on our website if you so choose later. So without further ado, let's get started. Dr. Jeff Abbott, if you could please join me at the podium to introduce our speaker.

Thank you, Dean Stamos. So hello everyone. My name is Jeff Abbott. I'm Professor of Physiology and Biophysics, Vice Dean for Basic Science Research, and Senior Associate Dean for Academic Personnel in the School of Medicine here at UCI. I'm delighted to introduce tonight's speaker. Thomas Arcek is a distinguished professor of biochemistry at the University of Colorado Boulder and investigator at the Howard Hughes Medical Institute. He is most recognized for his discovery of self-splicing RNA, which provided the first exception to the long-held belief that biological reactions are always catalyzed by proteins. This discovery has been heralded as providing a A New Plausible Scenario for the Origin of Life. So let's think about the ramifications of that while we listen to his lecture tonight. Because RNA can be both an information-carrying molecule and a catalyst. Perhaps the first self-reproducing system consisted of RNA alone. So it's incredible. Imagine the origins of all life on the planet could come down to this. Dr. Scheck is a recipient of many national and international awards. And prizes, including the Heineken Prize of the Royal Netherlands Academy of Sciences, 1988, the Albert Lasker Basic Medical Research Award in 1988, the Nobel Prize in Chemistry in 1989, and the National Medal of Science in 1995. In addition, Dr. Cech was elected to the National Academy of Sciences in 1987, the American Academy of Arts and Sciences in 1988, and the National Academy of Medicine in 2000. He was a Howard Hughes Medical Institute, or HHMI, investigator from 1988 to 2000. In 2000, he became president of HHMI. He resumed his full-time investigator status in 2009. So tonight, please join me in welcoming our Dean's Distinguished Lecture Series speaker, Dr. Thomas R. Cech.

Thank you both. Take care. Well, thank you, Jeff, and thank you, Mike. You've been such really warm hosts, and we have a number of faculty here at UCI who trained on my floor in Boulder, and so it's really been great to catch up with them as well. Mike Stamos first invited me to come here this lecture was about 3 years ago. And I thought, oh, that's great because I'll get a chance to see my daughter who was in the master's program in genetic counseling here in Irvine. And of course, she's now long gone because the pandemic intervened. And she's now at Seattle Children's Hospital practicing what she learned here. And I must say that the genetic counseling program here is really top-notch, one of the best in the country. And her experiences at the Orange Hospital actually practicing what she had learned in the master's program were also— it was also a really great experience. So I hope the dean is listening because this is a program that definitely is a— should be considered a core part of what you do. Because after all, with all of this genomic information coming through, people getting their— we're going to very soon be at the $100 human genome, for research purposes at least. If you do it for medical, it'll be $10,000, right, because there's all these markups. But still, it's getting so accessible that people are going to have their genome sequenced, and what do you do with that information, right? And so this is going to be the challenge that is for the next years, is to have genetic counselors and also just informed citizens who understand what you can learn from, and what you can't learn from, your genetic information. Now, I'm going to start by saying that this is where I work. It's the BioFrontiers Institute, which I helped found at the university. We bring physicists, computer scientists, mathematicians, and engineers together with biologists in this sort of radically interdisciplinary model, because we think that by bringing the different disciplines together, you can solve tomorrow's biomedical problems better than if you're just narrowly trained. And it's been very exciting to not only hire faculty who work on these diverse areas. The last faculty member we hired works on mites that infest honeybees and are the main cause of the demise of the pollinator population. So that's not something you would normally hire in a medical school, but we find it is very exciting to, to have this real mix of not just molecular biologists but also biophysicists, computer scientists, et cetera. The— and I also have to disclose my being on the scientific advisor of these 3 companies listed at the bottom, although they don't know what I'm going to say today, and I'm not going to pitch anything that they are particularly doing. So I've been going around giving public talks about RNA, because I think we did a bad job during the pandemic of helping the citizens of our country and of the world understand what this vaccine was about. I think we told them that they would be naughty if they didn't take it, that they had to be vaccinated. I don't think that was a very successful approach. So instead, I'm just trying to explain to people what RNA is about, and then they can make their own decisions about whether this— they think this is a good thing or not. And so I start out always with something very simple. DNA, as you all know, is double helix. RNA is a single strand. We'll come back to that, because that turns out to be not just a trivial difference between the two, but in terms of information content, in terms of bits of information, they are identical. Because the A's, G's— this is too weird. I'm not going to use this. Because the A's, G's, C's, and T's on one strand of the DNA are directly recapitulated in the A's, G's, C's, and U's, U being very informationally the same as T. In the RNA. Okay, so double-strand DNA is copied into RNA without any loss or gain of information in the process. Now, you've all now heard about messenger RNA. This is the big difference, right? A few years ago, people said, oh, RNA, I don't know what that is. That's very complicated. I don't want to hear about it. Right now, everybody at least has heard about messenger RNA. And the reason, of course, is this beast over on the right-hand side here, which is the SARS-CoV-2, the coronavirus. And on the left, you see— and it's not quite to the right scale, but they are very similar in size, these lipid nanoparticles which carry the messenger RNA into our arms and then allow our immune system to get instructed to be on the lookout for the virus. These lipid nanoparticles are actually very similar in size to the virus itself. And the idea is that the RNA— and Phil Feghner, who's here, tells me that there's not one molecule per lipid nanoparticle. It's more like 4 to 6. OK, so the cartoon isn't quite right in that regard. But these are a way, as we will see, to protect the RNA and also to help it enter cells, which the RNA by itself is not good at. So this is an essential part of the mRNA vaccines. So when you read— listen to the news or read magazine articles or books, you often get the wrong impression about mRNA. It's treated as it's some kind of a foreign substance. It's like a medicine. It's a drug. And I think that for many people in the community, that is frightening. And so they, they're hesitant about mRNA because They think it's something that the pharmaceutical industry has created out of nothing. But of course, it's very natural. You might even say it's organic. It's in every food that we eat, and it's in every cell in our body, and it's doing this job of being a messenger between the code that is in our chromosomes and the protein that is made in our cytoplasm of our cells on little machines that are called what? Protein synthesis happens on— ribosomes. See, all these high school students know all this stuff. It's the rest of you who I'm talking to, OK? So this was actually predicted by Jacob and Monod and Sydney Brenner, Francis Crick, before messenger RNA was ever seen in living systems. Because the DNA's hanging out in the cell nucleus. And the proteins are being made in the cytoplasm on the ribosomes. And so there's no way that the DNA code can directly instruct the synthesis of proteins. There must be an intermediate. And that intermediate was predicted to be RNA and took a long time to find it because it's a small part of the RNA in each of our cells, just a few percent. And it's very heterogeneous because Every gene makes its own message, and so it's of a different size and composition than the RNA made from a different gene.

Okay?

So it took a while to find this. But when they finally found it, the next big question was, what was the code? There had to be a cipher that would be responsible for instructing a particular protein. To be made. And unfortunately, there was no Rosetta Stone. There was no way, there was no stone in which the Egyptian hieroglyphics were written out in rows, and then the Greek was written out in rows for the same message underneath. That would make it very easy to translate the language of nucleic acid DNA and RNA, into the language of protein. So there wasn't a Rosetta Stone, and therefore it took a lot of hard work for the scientists to come up with this answer to the question, here is the code. And it didn't actually take very long. It was about a 5-year hunt. And that's because it was the most important question in biology at the time. So people were really focused on answering it. And it's just sort of a beautiful table here. If you want to design a messenger RNA to encode a particular protein, like for example, the coronavirus spike protein, because you want to make a vaccine, then you simply start with AUG, which means that this is where protein synthesis starts. Methionine. This is right there. I promised I wouldn't use this thing, but here I am using it. And it's sort of fun, actually, to play with this. And then if the next amino acid is a threonine, for example, you have your choice of 4 different tri— codons, groups of 3 nucleotides, for threonine. And if the next one is a phenylalanine, you've got a couple of choices up here. And then finally, if you want to stop making that protein, there's a stop codon in the code, which is one of the 3 that's in boldface on the upper right. And so now any high school student, all of you guys, you've probably done this in class, right? If you're given an amino acid sequence, you can come up with an mRNA string of letters that would make it. Or vice versa, if you are given an mRNA sequence, you can write out what the protein sequence would be. And it's almost universal in all of life, from bacteria to the archaeobacteria that inhabit hot springs in Yellowstone National Park, to eukaryotic organisms that have a separate nucleus and cytoplasm, which would include everything from Tetrahymena, that I'll talk about later, to yeast, to mice and humans and plants. So what does a vaccine do? Well, it sort of gives a heads up to our immune system. It primes it. It says, if you ever see this again, do something about it because it's not good, right? And so the key is, though, it's the same principle as a real virus infection. That's why once we have a particular virus, we get some immunity against having it again because a real virus also primes our immune system to be on the lookout for it. Unfortunately, you get really sick the first time around. But the vaccine is not infectious because it can't replicate in our bodies and make more of itself. So it just presents the thing to be on the lookout for. And for the coronavirus, that thing is the spike protein, right? Something inside of the virus wouldn't be visible to our immune system. It has to be something that is displayed on the outside. So that is shown here in this false-colored— it's not really red like this, but all the pictures have it red. So we'll keep it red. So how do you make, then, the spike protein to use for inoculation to vaccinate people? Well, since we know that DNA makes messenger RNA makes protein, and in this case, we want the spike protein, We could start out with DNA or we could, in fact, you know, we need some way to make the protein. But what the really smart people at Moderna in Boston and at BioNTech in Mainz, Germany decided was that, you know, you don't really need the DNA because the mRNA is all that you need in order to instruct the synthesis of a particular protein. And so they had been working on mRNA vaccines for cancer The pandemic hit and they were sort of thinking this was going to be an opportunity for them to make a difference in the world. And so they jumped on the sequence that was very bravely put on the internet by some Chinese scientists in January. And by the end of that year, by the end of 2020, December, they already had a vaccine that they were hoping would have 70% protection because that's a good— that's considered to be a really good vaccine. Sometimes the flu vaccine is, you know, 20%, 30% protective. And when they found out that it was 95%— and this is the first mRNA vaccine. Usually the first time you do something, in the, in the biopharmaceutical industry, it doesn't work at all. They got 95% efficacy in both Moderna and BioNTech. So that was a real triumph. The major advantages of these mRNA vaccines relative to traditional vaccines, first of all, you get this amplification. Each mRNA is translated into about 1,000 spike proteins before it gets naturally chewed up in our body and inactivated— before the mRNA gets chewed up and inactivated. So you get a 1 to 1,000 amplification, which is a good thing. Adaptability. It's very quick if a new viral variant comes along. Any of these students in the front row could tell you which codons on the mRNA you needed to change to adapt it to the new variant. And that's why the last shot that I got is this bivalent one that is against the two versions of the new Omicron as well as the original SARS-CoV-2. And then finally, it has a safety advantage because there's no— a lot of the old-fashioned vaccines were heat-inactivated or debilitated viruses that weren't very good at replicating. And there's always sort of a little bit of queasiness about this because are you really sure that they aren't going to be able to replicate? Here, there's no chance that this thing could become infectious. But there are also considerable challenges with these mRNA vaccines, as I've already alluded to. RNA is not very stable. That's important for its normal role inside of our bodies. Because if the needs change and you want to express different genes, because you're differentiating into a different cell type, or because you have a different environmental sort of— different environmental conditions to respond to. You don't want to keep making the same proteins. You want to be able to make different proteins. So you have to degrade the mRNA and now make new mRNA that's more suited to the new opportunities or challenges. So that's good for biology, but it's sort of not so great for a vaccine. RNA does not get into cells. Turns out RNA is a highly charged molecule. It has a negative charge. At every one of those A's, G's, C's, and U's along the chain, and that does not get through the membrane of cells. And finally, RNA can trigger innate immunity because we have systems within that have been developed through— in our bodies that are on the lookout for RNA because RNA often means virus. And so there's this sort of very ancient Fruit flies have the same system, very ancient system of innate immunity, and it causes inflammation. It can cause a lot of side effects if it's inappropriate, and so that can be a problem. So the way that this was solved, these problems were solved in making the mRNA vaccines, was in terms of the stability, of course, cold storage, which is sort of a bit of a challenge for distributing the vaccine, but it's much more stable at very low temperatures. These lipid nanoparticles also sequester the RNA away from enzymes within our bodies that would be degrading the RNA. And then the fact that RNA doesn't get into cells can be solved also by these lipid nanoparticles. Because, as shown in the cartoon on the upper right, this is actually the way that viruses get into our cells as well. There can be a fusion of this greasy coat around the RNA, this lipid coat, with the lipids on the surfaces of our cells. And that allows the material to get from the outside to the inside because this negatively charged RNA is hidden and isn't a problem until after it gets in the cell. And then it can get released. And then in terms of this RNA triggering innate immunity and inflammation, it turns out that if you substitute— and this was not easy to figure out— but if you substitute a sort of a turned-around U, it's called a pseudo-U, for the U in RNA, then that's enough for our innate immune system not to think that this is an invading virus and to sort of say, OK, we'll stay away. You're OK, right? Because you don't look like real RNA. But this modification does not prevent the RNA from acting as a message. And so it still makes a spike protein. So that was sort of a brilliant addition to all of this. Now, how was it possible that all this happened in just a year? How could this— how could the first mRNA vaccine be so quick and so successful? And it was really because taxpayers' dollars, your dollars and mine, through NIH funding, through other sort of federal support of biomedical research, had funded fundamental research into RNA and how it works independent of any applications. Certainly independent of SARS-CoV-2 because this had been going on for decades before the pandemic, right? And so it's so important for us just to understand how biology works, and then this storehouse of information then can be quickly tapped into when the need arises. And here are just a few examples. RNA sequencing allowed us to reveal this sequence of the spike protein messenger RNA very quickly, but it wasn't developed for that purpose. Virology, understanding how the spike protein allows the virus to enter our cells, nucleic acid chemistry, this pseudo-U modification to make the RNA stable and safe, RNA biochemistry to understand how to make truckloads of RNA to be available for the vaccine. That technology goes back to the, to the 1980s, and it was just being used for strictly research purposes, but now it had an application. And then the fifth one maybe shouldn't really be on this list, because a lot of the work on lipid nanoparticles was really done in companies rather than by so much by NIH-supported work. But there was also some of that. OK, now you may think I've timed this very badly, because I'm done with mRNA. You may say, well, we can all go home early. But it turns out that there are a lot of functions of ribonucleic acid in all of our cells that don't even care about the genetic code table, as beautiful as it is. And that's because RNA, being a single-stranded molecule, can fold up within itself, within the same molecule, into an almost limitless number of shapes. And shape in biology allows function. And so the opportunities for non-coding RNAs are an enormous list. And in fact, there's been 2 Nobel Prizes given so far for messenger RNA. There have been about 10 so far given for non-coding RNAs, because they do such diverse things. And I'm going to give just 3 examples tonight, because we don't have— I mean, I would love to talk about this till the sun comes up tomorrow morning, but we're not going to do that. OK, so the 3 examples are going to be that RNA can be a biocatalyst, a function that was previously thought to be restricted to protein enzymes. We called these ribozymes, meaning ribonucleic acid with enzymatic function. RNA can make you immortal, or your cells at least. But be careful what you wish for. You'll see that in a minute. Telomerase RNA. And then finally, RNA can guide the editing of our genomes, which is going to be an enormous opportunity for medical advances in the very near future, because this CRISPR genome editing is so powerful that it's quite easy to get it to work. So let's do the first one. RNA can be a catalyst. This is the story when I first moved from MIT as a postdoctoral fellow to Boulder for my first faculty position. I started working on this organism, Tetrahymena, thermophila found in freshwater ponds throughout the world. And the reason I liked it was because in its large macronucleus, it had 20,000 copies of a particular gene. And if you're a chemically oriented biologist, 20,000 copies of a gene is like a lot to work with. Most genes in Your bodies, high school students again, how many copies do you have of a particular gene in most of the cells in your body? Go ahead. Not yet? OK, over here. This team. 2, yes. 1 from mom and 1 from dad, right? So there's a big difference between 20,000 and 2. And so we started looking at this gene, and it was— had its functional sequences interrupted by a stretch of non-coding, sort of nonsense, we thought, DNA called an intron. This is very common in the genes of higher organisms. It's a distinguishing factor between the genes of eukaryotes and the genes of bacteria. And it was already known at that time that that sort of interruption in the functional sequences was copied during the process of transcription, did not distinguish between the so-called exons and the introns. And then there was something happening in the cell, something a little more sophisticated than the scissors, that would cut out that intron and stitch together the meaningful sequences. And this was happening in a typical human gene will have 10 of these interruptions. And so this is a very common phenomenon. But at the time, nobody knew how these sequences got spliced out. So we were studying the process of the RNA being made. From the tetrahymena gene and kept noticing that the splicing was taking place in the test tube. And if you're a biochemist, getting a reaction to take place outside of the living cell in a test tube is the first step towards understanding its mechanism. And it was happening, coming along sort of for free. So we started looking for the protein enzymes that were responsible for the cutting and the pasting of the RNA, because everyone knew, it was in all of the textbooks, that all biochemical reactions are catalyzed by protein enzymes. So there had to be proteins. But yet we had extracted the RNA with detergent and high temperature, boiled it, do all kinds of things that should be really deleterious for protein function, and the splicing continued. So this brings us to a departmental Christmas party a long time ago when my graduate student Paula gave me this as a Christmas present. So was there a protein, really, in there that was surviving all of these steps and doing the splicing or not? And it turned out it was not. It was the RNA by itself was folding up the intron part of the RNA. Was folding up and making a catalyst for its own splicing. And this is what we called self-splicing. And there was a whole community of researchers who were excited about this, because they had been thinking not about Campbell's primordial soup— but you can't actually get that at the grocery store— but they'd been thinking about what happened on the primitive Earth almost 4 billion years ago when the inorganic suddenly became an organic self-replicating system. And it had been hard to think about this, because if, in order to go from one generation to the next, you need some informational molecule to be passed down, well, we know in current biology that's DNA. And we need some kind of a process for copying the DNA into the daughter DNA molecules. Well, that's a protein enzyme. So pretty tough to think about the origin of life if you need at the same moment an informational molecule and an enzyme that can reproduce it forming by random chemical events. Now that we know that RNA can be both informational molecule and a biocatalyst, maybe at the beginning there was just RNA, and then the proteins came along later. And the DNA is probably a very recent invention on this sort of time scale, of course, not that recent, but because the DNA is a more stable storehouse of the genetic information. So this led to the 1989 Nobel Prize in Chemistry, and allowed my older daughter to meet the King and Queen. And our younger daughter was too young. She wasn't allowed to come. So she went out to McDonald's in Stockholm with a driver. So the second story is about non-coding RNAs, is that RNA can bestow immortality. Now I have to lead up to this a little bit to say that these are human chromosomes that are condensed because they're in the process of cell division. And they're decorated by— to highlight the nucleic acid, the DNA sequences at the very ends of the chromosomes. You can see there's something that's at all of the ends of all of our chromosomes, a particular DNA sequence. And part of the reason for this is because it protects the ends of our chromosomes, just sort of like the plastic tips on shoelaces prevent our shoelaces from unraveling. Who knows the word for the plastic tips on shoelaces? Yes? Aglets. Aglets. Yeah, there you go. So I didn't know that until after I made this slide. OK. So it turns out that as progressive cell divisions go on, in most of our body cells, these chromosome ends are not copied. They're not replicated the way the middle parts of the chromosomes are. So this telomere DNA shrinks as the cells divide. And when it gets critically short, then the cells stop dividing.. And we think that that's probably a tumor protective mechanism because the activation of this process is a very common step, a required step, in a lot of cancers. So it's really the— here's a cartoon of what this enzyme now that is responsible for building out the ends of chromosomes and is reactivated in cancers is called telomerase. And it is a collaboration between the purple strand, which is an RNA strand, and a protein, which is the catalytic center. So it's not a ribozyme. The RNA is not catalytic. But what is the RNA doing? It's serving as a template to determine what sequence is laid down at the ends of our chromosomes. And then the protein part, called telomerase reverse transcriptase, or TERT, is responsible for catalyzing the addition of these repeated sequences at the ends of our chromosomes. It's a repeated sequence because it just makes a little 6-nucleotide sequence, then it ratchets back and does it again. And does it again. So this enzyme is kept at a very delicate balance because it is a step, a foot in the door for cancer if you have it activated, because this allows cancer cells to be immortal. But on the other hand, if you have too low of telomerase levels, and there are many human diseases that are caused by this, for example, the ones mentioned here, then your stem cells, which do need to keep dividing, don't proliferate actively enough. And so they poop out, in other words. That's a technical term. So let me then go on to the third topic, which is RNA can guide genome editing. And this is this CRISPR system, which bacteria have known about for many millions of years, but we only found out about it fairly recently. And this was the reason for the Nobel Prize in Chemistry being given to Emmanuelle Charpentier and Jennifer Doudna, who collaborated to understand how this bacterial antiviral system could be repurposed to edit genes in crop plants and mice and even in human cells. And we were particularly excited about this Nobel Prize in Boulder because Jennifer had done her postdoctoral work with me in my lab. In Colorado. So here we all are in a lab reunion in 2007. So what— how does this work? Well, again, this is oversimplified. The red scissors is really not quite how it works, but it does cut both strands of the double-stranded DNA. And you might wonder, why is that a good thing? Why is that useful? Why isn't that just a bad thing? I'll get to that in a minute. And the way that it finds this very specific spot in this vast array of chromosomal DNA in all of our cells is that it uses— it carries along with it a guide RNA. And only when the guide RNA can form AU and GC base pairs with the DNA strand does it lock down and cut the DNA at that point. So the RNA— it's a protein called Cas9 that does the cutting. It's the RNA that acts as a guide. Wow, really similar to telomerase, right? The RNA and the protein each have sort of like a division of labor. Now after the DNA is cut, then cellular repair machineries go to work, and they can do one of two things. They can either just stitch together the broken DNA, and when they do that, they often add or subtract a few nucleotides along the DNA code. And that's enough, usually, to inactivate a gene, even though it's a small change. And the other thing that can happen is its technical term is homologous DNA recombination, HDR, is that they can— it can use a donor piece of DNA and substitute that for the natural sequences. And so it can actually add new sequences into the DNA. And this was sort of the version 1.0 of CRISPR genome editing, but now we have new versions. A lot of this is due to a brilliant Howard Hughes investigator at Harvard University named David Liu, who has figured out that CRISPR can be used not just to cut DNA, but versions 2 and 3 are to actually change base sequence without going through this complete cutting step in the middle. So the research applications of this technology have been exciting for really ever since it was discovered almost a decade ago. And for example, for research purposes, we can inactivate a particular human gene and then see what are the consequences, and that helps us understand the function of that gene. We can edit a single base pair in a gene to repair a mutation. For example, sickle cell disease is caused by just a single change in the beta globin gene, which makes then a slightly weird hemoglobin in our blood cells of the afflicted individuals. And then tends to cause them to undergo this aggregation. The hemoglobin aggregates and forms this sickle shape of the red blood cell, which is painful and can be even deadly. So if we want to know, is that really the cause of sickle cell disease? I mean, we know that it is, but we can go in and we can repair that in the laboratory, and we can prove that that really is the cause. And then the last thing, and I'll show one picture of this, is we can add sequences encoding a fluorescent tag to follow a protein as it explores a living human cell. And I'm going to need IT help back there in the— there, because I think— I don't have control over this. Can you— do you have a way of making this movie play? You just— if you run the— mouse over on the bottom there. Yeah, thank you. And so I never thought I would live long enough to see a technology where you could watch individual molecules of your choice moving around in real time in a cancer cell. But this is what we are now able to do. So before we play the movie again, let me explain this. The red dots are chromosome ends. And the reason that you only see a dozen of them there is because we're focusing down on one plane of the cancer cell nucleus. So we're not seeing the things that are out above and below. The green dots are telomerase molecules. And you will see that they are— exploring the nucleus, sort of looking for telomeres that they need to extend. And then there's one place, and I want you to focus right on this yellow dot right there, because green plus red makes yellow. And so this is a place where the telomerase has found a telomere, a chromosome end, and is staying there for an extended period of time. We have reason to believe that that's the moment it's actually extending. The telomere. So play this movie again, and everybody can watch that yellow dot. We've got to go back. Thank you. You'll see the green and the red sort of kissing each other during the entire movie. So that's one. And it was by CRISPR genome editing that we were able to put these sequences encoding a fluorescent tag into these natural human genes so we could follow them around in the nucleus in the microscope. But how about medical potential? So how about deleting bad genes? We can do this in the laboratory. I said we do it for research purposes all the time. How about for medicine? Yeah, there are some cases where you would like to just get rid of a gene. But I'd say that has fairly limited uses. Certainly some, for example, integrated human immunodeficiency virus DNA is something we'd like to get rid of, inactivate. So there are some applications. But I think the big potential is repairing faulty genes. Because most diseases are either genetic in origin Or they have some genetic component, something that is helping the disease progress. And so this is really where the, the big potential is. And there are already multiple clinical trials going on with multiple companies. Companies are doing these, and there are long-lasting devastating diseases like Duchenne's muscular dystrophy that are very deadly for teenagers when they get it. And these are actually on the horizon that we may be able to do something about them. But at the same time that there's all this potential, there are ethical concerns about the use of this technology that we should not brush under the carpet. Right? And for example, if we did germline editing, in sperm or eggs or very early embryos, then these changes would be inherited to the next generation. And that means that we would make permanent changes in humankind. And so that's something that people are concerned about and not ready for, frankly, for good reason. Safety issues. Can you really— it's highly specific, but nothing is perfect. And so you might think you're editing a particular gene. You might also inadvertently be editing some genes you don't even know about. And so that needs to be thought about. If it can be used to reduce pain and suffering, I think there will be a lot of community interest in going ahead with such treatments. But what if it can be used instead to enhance your height or your weight or how strong you are? I think that then the ethical concerns are— these are called enhancements, right? So then I think the ethical concerns are more daunting. What if the advantages are only available in a few countries or only available to the rich? How accessible will these technologies be? That's another ethical concern. And then the final question is, should we try to manage these issues or simply ban the use of CRISPR in humans? And so I think the decision has been made, at least now, to go ahead and use these for chances of reducing the pain and suffering due to, for example, genetic diseases, but to be very careful about not crossing the line for germline editing. So in conclusion, I have tried to get you excited about the fact that RNA is a message. This is a wonderful moment. I think it's equivalent to our putting a man on the moon, the fact that we could make these mRNA vaccines. And it was the knowledge of that RNA is a message that enable this to be done. But beyond being a message, these non-coding RNAs do wondrous things, including being biocatalysts, something we thought only proteins could do, bestowing immortality, which is either a good thing for your stem cells or a bad thing for cancer, and guiding the sites of CRISPR genome editing. And my research group thanks you who did all the hard work that allowed me to give this talk tonight. Thanks you for your attention. Thank you.

Thank you, Dr. Cech. Thank you, Dr. Cech, for an insightful journey through the marvelous molecule RNA. That was truly inspirational. And I think you did get everyone excited.

So thank you.

We have time for a few questions from the audience. Please raise your hand and wait for the microphone to make its way to you.

Professor Satch, I have a question about telomerase activity. So it looks like if we make an RNA in telomerase longer, then we can make our lives longer. Is it true, or is it not so easy?

I think that making a cell, a single cell live longer is not the same as making an organism that has many billions of cells live longer. So just because each of the cells in your body can continue dividing would make you maybe really ginormous, right? I mean, it's important that there be controls over how many times cells can divide. So I think it's not likely that you could make humans live, have an extended lifespan, but I think you could ameliorate the devastating effects of certain stem cell deficiencies that are causing people to get old faster by more targeted activation of telomerase in those stem cells. Thank you for your question.

Dr. Donovan.

Tom, thank you for a great talk that was very accessible, I think. You made an important point in terms of the development of the coronavirus vaccine about the long-term investment in basic research. And when you were president of the Howard Hughes Medical Institute, you had the ability to invest millions and millions of dollars in research, did you ever think to yourself, oh, if I invest in this type of research, I could affect human health? Or were you not that able to make those types of predictions?

We, we had the power to make those kinds of decisions, but we really sort of decided not to, and not to take the human health opportunities as a very major reason for funding research. And I think the coronavirus is a great example. All of these things like in vitro transcription of RNA was not developed to make vaccines. It was developed just to be able to make a lot of RNA. To, to study it. So often this undirected fundamental research will have diverse medical opportunities that cannot be predicted at the time. And the other thing is that the Howard Hughes spends about $1 billion a year on research. The National Institutes of Health spend in excess of $30 $1.5 billion. So we're a few percent of the total sort of pie, and since the NIH is so committed to doing translational research that will have medical applications, it seemed wise for a large but much smaller institute like Howard Hughes to be focusing on the fundamental science.

When you say you focused on the fundamentals, Could you say, out of the fundamental research that the Howard Hughes Medical Institute funded, without making a prediction from the start, what ended up being really important for human health?

Well, I think a good example is a Hughes investigator by the name of Bob Horvitz, who is at MIT, got the Nobel Prize. He's a longtime Hughes investigator. Friend of mine, got the Nobel Prize for watching the transparent nematode worm develop in the microscope and how one cell would divide to make two cells and then those two cells would divide to make three cells because one of them underwent programmed cell death. Turned out to be one of the most important one of the most important findings in tumor suppression in humans. And it was found by watching a transparent little worm divide without any idea that it would be important for humans. How about in the front row here? We have a high school student. Thank you for your talk. Oh, okay.

I just have a quick question. You did a great job of explaining how RNA can be used in vitro for, you know, single-cell organisms, but is there any hope for adult organisms, fully-fledged organisms affecting every cell at the genetic level for, you know, an adult organism?

I sense some skepticism in your question, and I shared this when I when I heard about Eric Olson's work on muscular dystrophy from UT Southwestern in Texas. Because by the time the kids are diagnosed with muscular dystrophy, the absence of this dystrophin protein has already, you know, caused some damage. And you wonder whether a kid still has enough sort of developmental potential to recover from this. So when they tried this in a muscular— a dog model. There are— in England, there are dogs that have the same genetic defect as humans have in muscular dystrophy. And he was able to cure these dogs even though they were already, you know, puppies and they had already developed for a while. So it seems like in many cases there's enough plasticity in human development that if you fix something— you'd like to fix it at time zero, but if you fix it at some later time, it can make a life-saving difference. I think each disease will be a different story.

So I have a more personal question. So I was wondering what skill sets that were either non-academic or academic have helped you succeed in your research and life?

I'm sorry, I got the gist of your question, but I missed a key word. Key words. So it's something about make a difference in my life.

Like, what skill sets, I guess, or like advice, either academically or non-academically, have helped you succeed in your research and/or your life?

So advice to you in particular.

How'd you get the Nobel Prize?

I think, you know, use your talents for something that you have a passion for, for something that you really, really lights your fire, that really you enjoy doing. Don't do something just because your parents tell you that this would be a good career for you. You have to do something that you really believe in and that really— because if you decide to be a scientist, it's sort of like 3 steps backwards for every step forward. There's a lot of discouraging times, and you have to really want to do it for it to be worthwhile doing it. Thank you for that.

We have a question over here at the back.

Thank you, Dr. Jack. This is Martin. I'm a fourth-year PhD student in civil engineering, pretty different from medical. I have a question.

But you're building bridges just like we try to do, right?

Yeah, yeah. Do you have any suggestions or advice for those who are pursuing their grad school, like us, doing engineering or science? And my second question is, when you are doing science, what are some of the rules or principles that you stick to?

Thank you. Yes, so do I have any advice for graduate students? Well, I have on my lab website a whole section called philosophy. And so I have, with the help of the people in my lab, we actually wrote down what we think are our principles of how graduate students should work and how I should, as a director of the graduate students, my responsibilities for helping them. I think they should get to the point where they take ownership of their project. And not maybe from the very beginning, then the head of the lab is sort of instructing them about what would be a useful direction to go, but the important moment comes when the student starts making those decisions. And I tell the students, I don't want you to come, come to me to ask me what to do next. I want you to come to me and tell me what you think you should do next, and then I'll listen, and then I'll have some suggestions. Yes, we have one here first, I think.

Um, I wanted to ask what made this research specifically difficult, and how did you overcome those challenges?

Well, so the thing that— when we're doing research right at the edge of knowledge where we don't really know the answer to the— we don't even know if our hypothesis is correct. Like you saw with the self-splicing RNA, the hypothesis was there was a protein in there and it turned out there wasn't. So when you're working on the very edge of what is known, in science, there's gonna be a lot of false leads, a lot of dead ends. So there are also technical problems, but those you can usually overcome by talking to other people and getting good advice, getting better reagents or whatever. But then there are conceptual problems. You just have the wrong idea. And so that's why it is so difficult. And often takes so long to make progress. Yes, better do it now because if you don't talk now, they'll never get to you.

Thank you. Well, so obviously I think mRNA based on your talk has a lot of potential. So I wanted to ask you, what do you think are some of the most unaddressed issues both in the medical and the research world that can be addressed by this mRNA technology or some of the most issues or the issues that you think should— people should be paying the most attention to?

Yes, I think the— thank you for that question. I think the big frontier is in terms of how the brain works and also in terms of various mental illnesses. I— and especially ones like schizophrenia, manic depressive illness. You know, there's probably some genetic predisposition, but it's not anything as simple as a single gene or a few genes. And so I think understanding normal cognition and aberrant neurological central nervous system defects is the big frontier.

2 more questions. This gentleman over here. We have one there as well.

Thank you so much for that talk.

Someone from the humanities.

Indeed. I'm piggybacking off your word philosophy, and this question comes from a humanities professor, so it could be supremely irrelevant, illiterate in biology. But the question is this: in all of this research, how would you differentiate between these two attitudes? One is how to coexist with a virus. The other one is how do you triumph over or defeat a virus? It's a matter of coexisting. You know, longevity is either good or bad. Good for the human being, but good for the cell. It's a question about anthropocentric research, humanism, and the scale of the research. I want to coexist with, in a certain way, but not die. But not kill it either because that is completely utopian and in a sense insane.

Well, of course, this is the big societal question that we've been dealing with for the last 2+ years and I think different people in the audience will have different opinions about whether we struck it right or not, right? But In defense of how we handled it as a society, it was a pretty new, we didn't have much time to think about this. It hit us very suddenly. And I think we did a pretty reasonable job. I do not blame the people who did lockdowns because you just don't know. And now we're seeing some of the negative effects of maybe, like you said, should we just coexist with it? Well, now we're doing the coexisting model, but many of you are still wearing masks, and I applaud that because I think it's a personal decision about how careful you need to be. So we don't have the answer.

Dr. Cech, thank you for that wonderful lecture. My question has to do with sort of RNA as a, information transfer and thinking about the efficiency of information transfer and whether you think there's a reason that the genetic code is 4 nucleotides, which is basically 2 base pairs, and then the triplet codon. And is there a reason to think that that's the most efficient form of information transfer? And I guess as a corollary, is there any evidence of any life forms that used anything other than 4 and 3?

No, the variations in nature of the genetic code are rather modest. For example, repurposing one of the stop codons to encode an amino acid, so pretty subtle things. I think that the— Just because of the time, let me answer the question about the triplet code. And so if you just do the— as George Gamow, the nuclear physicist, when he got really excited about Watson and Crick, started this thing called the RNA Tie Club in 1953 and tried to intuit what the genetic code would be like. And he figured out that it must be a triplet code because if you have 20 natural amino acids and you have a doublet code, then there are only 16 possible combinations. And 16 isn't enough to do 20, but 3 makes 64, which is enough to do the 20 and gives you this redundancy that we saw in the table. So it does sort of make sense that that is— you can think of more complicated ways that you might be able to do it with a doublet code, but it's not used.

Thank you everyone so much for your insightful and thoughtful questions. We could do this all night, but we do need to allow our Nobel laureate to get some rest tonight before the— he gives the keynote lecture tomorrow morning in the RNA symposium. So I will pass it over to Dean Stamos.

Besides, I can't stand here and hold this for very long. It's actually very heavy. So, Dr. Cech, if when you check your bag they charge you extra for the weight, we'll pay it, okay? Thank you so much. It says UCI School of Medicine Dean's Distinguished Lecture, Thomas R. Cech, PhD, October 20th, 21st, 2022.

Please. Whoa.

Okay, sure.

Excellent, excellent.

Okay, take your name tag off.

Yes, step off the cliff here.

Exactly. Step off the edge. Before you leave, we'd like to thank a few people who helped make this event possible. First of all, our partners here at Beale Applied Innovation who offered us this beautiful space tonight. UCI Media for recording the video that will be available on our website. So this will be archived and available for you to see again or for you to tell your family or friends to watch. Our RNA Symposium partners, including Professor Yongxin Shi, Feng Zhao, Suzanne Sandmeyer, Clemens Hertel, and Peter Kaiser. They are hosting him tomorrow at the symposium. All the people behind the scenes in my office, including Rachel Correll, Claire Brainerd Draper, Marissa Vance, Emily Dowadoff, Jim Swinson, Jessica Banfield, Annie Trepaga, and many others. Thank you. And to the UCI School of Medicine Office of Research under the leadership of Vice Dean Daniela Bota, as well as Vice Dean Jeff Abbott. Thank you very much.

Tonight's host.

Please look to our website for upcoming events. We have two more lectures being scheduled. They've already agreed to come here and speak to us. Winter 2023, Dr. Richard Barron, hosted by Dr. Boda, focused on clinical research, and then Dr. Bodan Pomahok, hosted by Vice Dean John Gross, focusing on clinical medicine. We will continue to bring you speakers from industry and academia who are making their mark on the world of healthcare. Thank you all for joining us.