Denis Aristide Baylor (January 30, 1940 – March 16, 2022) was an American neurobiologist. He was professor emeritus of neurobiology at Stanford University. He is known for his research on nerve cells in the retina of the eye. He developed a widely-used method for observing the electrical activity of single rod and cone photoreceptor cells and described how they encode light stimuli.[2] Baylor’s work has been recognized by his election to the American Academy of Arts and Sciences, the National Academy of Sciences, and the Royal Society of London.[1][3]

Denis Baylor
Born
Denis Aristide Baylor

(1940-01-30)January 30, 1940
DiedMarch 16, 2022(2022-03-16) (aged 82)
Alma mater
Awards
Scientific career
FieldsNeurobiology[1]
Institutions
Doctoral advisorJohn Nicholls

Early life and education

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Baylor was born on January 30, 1940, in Oskaloosa, Iowa.[4] Baylor received his BA in chemistry from Knox College in 1961, where he graduated magna cum laude and was elected to Phi Beta Kappa.[4] In 1965, Baylor received his M.D. from Yale School of Medicine, where he was elected to Alpha Omega Alpha medical honor society and graduated cum laude.[1] At Yale, he was a postdoctoral fellow in physiology with John Nicholls from 1965 and 1968.[1] He then joined the United States Public Health Service and worked at the National Institutes of Health for two years in the laboratory of M.G.F. Fuortes.[4] From 1970 to 1972 he was a Special Fellow of the USPHS in the laboratory of Alan Hodgkin in Cambridge, England.[4]

Research and career

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Academic posts

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In 1972 Baylor joined the faculty of the University of Colorado Medical School, where he was associate professor of Physiology.[1] In 1974 he moved to Stanford University, where he was an associate professor of physiology up to 1975.[1] Baylor was then an associate professor of neurobiology between 1975 and 1978. In 1978, he became a professor of neurobiology at Stanford and chaired the Department from 1992-1995.[1] He became Emeritus in 2001.[1] During his career, Baylor has served on the editorial board for The Journal of Physiology, Neuron, Journal of Neurophysiology, Visual Neuroscience, and The Journal of Neuroscience. He served on the Scientific Advisory and Medical Advisory Boards of the Howard Hughes Medical Institute, where he was also a Senior Scientific Officer.[1] He was a member of the Lasker Awards Jury and was on the Visiting Committee at Harvard Medical School.[4] He served on the Visual Sciences Study Section of the NIH, which he chaired, as well as the advisory boards of multiple other foundations.[4][5]

Research interests and selected publications

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Denis Baylor is known for work on early steps in vision, in particular the mechanism in which light energy is converted to neural signals within the rod and cone photoreceptor cells of the eye. He provided a quantitative description of the laws that govern the process.[6][7][8][9] Using a new method for recording the electrical currents of individual cells[10] he recorded for the first time the response of retinal rods to single photons of light[11] and showed that the response is remarkably reproducible.

He also described and defined the molecular mechanism of two components of intrinsic photoreceptor noise that limit our ability to detect very dim light.[12][13][14]

His work revealed how light[15] and color[16][17] are initially encoded in the primate retina, providing a physiological basis for psychophysical results of Stiles on human vision.

He also helped to elucidate the molecular mechanism of a number of the steps that mediate and control the photoreceptor’s electrical response to light.[18][19][20][21][22][23]

Awards and honors

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Baylor's work has been honored by various awards, including election to the American Academy of Arts and Sciences (1992),[24] the National Academy of Sciences (1993),[25] and the Royal Society of London (2003).[1][2]

Death

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Baylor died of cardiac arrhythmia at the Stanford Golf Course on March 16, 2022, at the age of 82.[26]

References

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  1. ^ a b c d e f g h i j k "Denis Baylor's Profile | Stanford Profiles". profiles.stanford.edu. Retrieved March 29, 2021.
  2. ^ a b "Search | Royal Society". royalsociety.org. Retrieved March 29, 2021.
  3. ^ Lamb FRS, Trevor D.; Yau, King-Wai (2024). "Denis Aristide Baylor. 30 January 1940 — 16 March 2022". Biographical Memoirs of Fellows of the Royal Society. 77. doi:10.1098/rsbm.2023.0033.
  4. ^ a b c d e f Baylor, Denis "Curriculum Vitae" via https://profiles.stanford.edu/denis-baylor Archived December 13, 2019, at the Wayback Machine
  5. ^ "1996 | The Grass Foundation". www.grassfoundation.org. Archived from the original on September 19, 2020. Retrieved March 31, 2020.
  6. ^ Baylor, D. A.; Fuortes, M. G. F. (March 1, 1970). "Electrical responses of single cones in the retina of the turtle". The Journal of Physiology. 207 (1): 77–92. doi:10.1113/jphysiol.1970.sp009049. PMC 1348693. PMID 4100807.
  7. ^ Baylor, D. A.; Hodgkin, A. L. (October 1, 1973). "Detection and resolution of visual stimuli by turtle photoreceptors". The Journal of Physiology. 234 (1): 163–198. doi:10.1113/jphysiol.1973.sp010340. PMC 1350657. PMID 4766219.
  8. ^ Baylor, D. A.; Hodgkin, A. L.; Lamb, T. D. (November 1, 1974). "The electrical response of turtle cones to flashes and steps of light". The Journal of Physiology. 242 (3): 685–727. doi:10.1113/jphysiol.1974.sp010731. PMC 1330659. PMID 4449052.
  9. ^ Baylor, D. A.; Hodgkin, A. L. (November 1, 1974). "Changes in time scale and sensitivity in turtle photoreceptors". The Journal of Physiology. 242 (3): 729–758. doi:10.1113/jphysiol.1974.sp010732. PMC 1330660. PMID 4449053.
  10. ^ Baylor, DA; Lamb, TD; Yau, KW (March 1979). "The membrane current of single rod outer segments". The Journal of Physiology. 288: 589–611. doi:10.1113/jphysiol.1979.sp012715. PMC 1281446. PMID 112242.
  11. ^ Baylor, D A; Lamb, T D; Yau, K W (March 1979). "Responses of retinal rods to single photons". The Journal of Physiology. 288: 613–634. doi:10.1113/jphysiol.1979.sp012716. PMC 1281447. PMID 112243.
  12. ^ Baylor, D A; Matthews, G; Yau, K W (December 1980). "Two components of electrical dark noise in toad retinal rod outer segments". The Journal of Physiology. 309: 591–621. doi:10.1113/jphysiol.1980.sp013529. PMC 1274605. PMID 6788941.
  13. ^ Rieke, F; Baylor, D A (November 1996). "Molecular origin of continuous dark noise in rod photoreceptors". Biophysical Journal. 71 (5): 2553–2572. Bibcode:1996BpJ....71.2553R. doi:10.1016/S0006-3495(96)79448-1. PMC 1233743. PMID 8913594.
  14. ^ Rieke, Fred; Baylor, Denis A. (April 2000). "Origin and Functional Impact of Dark Noise in Retinal Cones". Neuron. 26 (1): 181–186. doi:10.1016/s0896-6273(00)81148-4. PMID 10798402. S2CID 14446202.
  15. ^ Baylor, D A; Nunn, B J; Schnapf, J L (December 1, 1984). "The photocurrent, noise and spectral sensitivity of rods of the monkey Macaca fascicularis". The Journal of Physiology. 357 (1): 575–607. doi:10.1113/jphysiol.1984.sp015518. PMC 1193276. PMID 6512705.
  16. ^ Schnapf, J. L.; Kraft, T. W.; Baylor, D. A. (January 1987). "Spectral sensitivity of human cone photoreceptors". Nature. 325 (6103): 439–441. Bibcode:1987Natur.325..439S. doi:10.1038/325439a0. PMID 3808045. S2CID 11399054.
  17. ^ Baylor, D A; Nunn, B J; Schnapf, J L (September 1987). "Spectral sensitivity of cones of the monkey Macaca fascicularis". The Journal of Physiology. 390: 145–160. doi:10.1113/jphysiol.1987.sp016691. PMC 1192171. PMID 3443931.
  18. ^ Zimmerman, A. L.; Baylor, D. A. (May 1986). "Cyclic GMP-sensitive conductance of retinal rods consists of aqueous pores". Nature. 321 (6065): 70–72. Bibcode:1986Natur.321...70Z. doi:10.1038/321070a0. PMID 2422559. S2CID 4371641.
  19. ^ Chen, J.; Makino, C.; Peachey, N.; Baylor, D.; Simon, M. (January 20, 1995). "Mechanisms of rhodopsin inactivation in vivo as revealed by a COOH-terminal truncation mutant". Science. 267 (5196): 374–377. Bibcode:1995Sci...267..374C. doi:10.1126/science.7824934. PMID 7824934. S2CID 27810310.
  20. ^ Xu, Jun; Dodd, Robert L.; Makino, Clint L.; Simon, Melvin I.; Baylor, Denis A.; Chen, Jeannie (October 1997). "Prolonged photoresponses in transgenic mouse rods lacking arrestin". Nature. 389 (6650): 505–509. Bibcode:1997Natur.389..505X. doi:10.1038/39068. PMID 9333241. S2CID 4419718.
  21. ^ Rieke, F.; Baylor, D.A. (October 1998). "Origin of Reproducibility in the Responses of Retinal Rods to Single Photons". Biophysical Journal. 75 (4): 1836–1857. Bibcode:1998BpJ....75.1836R. doi:10.1016/S0006-3495(98)77625-8. PMC 1299855. PMID 9746525.
  22. ^ Mendez, Ana; Burns, Marie E.; Roca, Angela; Lem, Janis; Wu, Lan-Wing; Simon, Melvin I.; Baylor, Denis A.; Chen, Jeannie (October 2000). "Rapid and Reproducible Deactivation of Rhodopsin Requires Multiple Phosphorylation Sites". Neuron. 28 (1): 153–164. doi:10.1016/s0896-6273(00)00093-3. PMID 11086991. S2CID 15566399.
  23. ^ Burns, Marie E.; Mendez, Ana; Chen, Jeannie; Baylor, Denis A. (September 2002). "Dynamics of Cyclic GMP Synthesis in Retinal Rods". Neuron. 36 (1): 81–91. doi:10.1016/s0896-6273(02)00911-x. PMID 12367508. S2CID 17139873.
  24. ^ "Denis Aristide Baylor". May 17, 2024.
  25. ^ "Denis Baylor". Archived from the original on January 31, 2020. Retrieved April 4, 2020.
  26. ^ "Denis A. Baylor Obituary". The Register-Mail. March 22, 2022. Archived from the original on January 26, 2023. Retrieved January 26, 2023.