Lifespan. David Sinclair
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103 Times as Many Cells as a Baby. About How Many Cells Does an Adult Have?,” Socratic, January 26, 2017, https://socratic.org/questions/a-newborn-baby-has-about-26-000-000-000-cells-an-adult-has-about-1-9-10-3-times-.
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C. B. Brachmann, J. M. Sherman, S. E. Devine, et al., “The
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It is one of the most interesting and important papers I’ve ever read. C. E. Shannon, “A Mathematical Theory of Communication,”
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Research by the authors showed that mTORC1 signaling in cancer cells increases survival by “suppressing endogenous DNA damage, and may control cell fate through the regulation of CHK1.” X. Zhou, W. Liu, X. Hu, et al., “Regulation of CHK1 by mTOR Contributes to the Evasion of DNA Damage Barrier of Cancer Cells,”
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E. J. Calabrese, “Hormesis: A Fundamental Concept in Biology,”
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Up to 69 percent of the human genome may be repetitive or derived from endogenous viral DNA repeats, compared to previous estimates of around half. A. P. de Konig, W. Gu, T. A. Castoe, et al., “Repetitive Elements May Comprise over Two-thirds of the Human Genome,”
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Just what do we mean by the word
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Dating back to the 1960s, every three or four years the center has published a catalog of its strains of
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Yeast researchers have interesting names. John Johnston and my adviser Dick Dickinson are just two of them.
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In 2016, Dr. Yoshinori Ohsumi won the Nobel Prize in Physiology or Medicine for his work on autophagy in yeast. That’s when cells stave off extinction during hard times by digesting nonkey parts of themselves. B. Starr, “A Nobel Prize for Work in Yeast. Again!,” Stanford University, October 3, 2016, https://www.yeastgenome.org/blog/a-nobel-prize-for-work-in-yeast-again.
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Dawes’s delightful tour of his experiences in the world of academe and cell biology research is a refreshingly direct and personal account of a remarkable journey into yeast research over four decades. I. Dawes, “Ian Dawes—the Third Pope—Lucky to Be a Researcher,”
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I also learned, the hard way, that I should not drink copious quantities of yeasty beer.
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For four years after that, I sent Professor Melton a bottle of red wine for New Year’s, just to say thanks for changing my life. He never acknowledged any of them or ever smiled at me, either because he didn’t think that’s what an awardee should do or because he’s a very private person. At least he knew I was grateful. The selection of red wine turned out to be ironic, as that foodstuff helped propel my career a second time nine years later.
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C. E. Yu, J. Oshima, Y. H. Fu, et al., “Positional Cloning of the Werner’s Syndrome Gene,”
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In a paper published in late 1997, I showed how ERCs—rDNA circles—cause aging and shorten the life of yeast cells. D. A. Sinclair and L. Guarente, “Extrachromosomal rDNA Circles—A Cause of Aging in Yeast,”
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One way to think of the epigenome is as a cell’s software. In the same way digital files are stored in a phone’s memory and the software uses the ones and zeros to turn a phone into a clock, calendar, or music player, a cell’s information is stored as As, Ts, Gs, and Ts, and the epigenome uses those letters to direct a yeast cell to become male or a female and turn a mammalian cell into a nerve, a skin cell, or an egg.
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I am not the first person to use this analogy. One of the earliest uses of the piano metaphor I can find came from a study guide intended to accompany a
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C. A. Makarewich and E. N. Olson, “Mining for Micropeptides,”
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D. C. Dolinoy, “The Agouti Mouse Model: An Epigenetic Biosensor for Nutritional and Environmental Alterations on the Fetal Epigenome,”
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The more extroverted you are, the longer your lifespan, while, perhaps unsurprisingly, pessimists and psychotics see significant increases in the risk of death at an earlier age. That’s according to a study of 3,752 twins 50 years or older that looked at the relationship between personality and lifespan through the prism of genetic influences. M. A. Mosing, S. E. Medland, A. McRae, et al., “Genetic Influences on Life Span and Its Relationship to Personality: A 16-Year Follow-up Study of a Sample of Aging Twins,”
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It was a eureka moment—discovering why yeast cells age. Supercoiled circles of ribosomal DNA pinch off the yeast chromosome and accumulate as the yeast divide, distracting the Sir2 enzyme from its main role of controlling genes for sex and reproduction. David A. Sinclair and Leonard Guarente, “Extrachromosomal rDNA Circles—A Cause of Aging in Yeast,”
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D. A. Sinclair, K. Mills, and L. Guarente, “Accelerated Aging and Nucleolar Fragmentation in Yeast SGS1 Mutants,”
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Sinclair