The rockefeller university

Event Details

Type

Special Seminar Series

Speaker(s)

Louis Ptacek, M.D., director, division of neurogenetics, and John C. Coleman Distinguished Professor in Neurodegenerative Diseases, department of neurology, University of California, San Francisco; investigator, Howard Hughes Medical Institute

Speaker bio(s)

Post-translational modifications play central roles in myriad biological pathways including circadian regulation. Dr. Ptáček's lab employed a circadian proteomic approach to demonstrate that circadian timing of phosphorylation is a critical factor in regulating complex GSK3β dependent pathways and identified O-GlcNAc transferase (OGT) as a substrate of GSK3β. Interestingly, OGT activity is regulated by GSK3β, hence OGT and GSK3β exhibit reciprocal regulation. Modulating O-GlcNAcylation levels alter circadian period length in both mice and Drosophila, and conversely protein O-GlcNAcylation is circadianly regulated. Central clock proteins, Clock and Period, are reversibly modified by O-GlcNAcylation to regulate their transcriptional activities. In addition, O-GlcNAcylation of a region in PER2 known to regulate human sleep phase (S662-S674) competes with phosphorylation of this region, and this interplay is at least partly mediated by glucose levels. Together, these results indicate that O-GlcNAcylation serves as a metabolic sensor for clock regulation and works coordinately with phosphorylation to fine tune circadian clock.

Dr. Ptáček earned his medical degree at the University of Wisconsin Medical School in 1986 and completed a residency in neurology at the University of Utah, Salt Lake City. He was chief neurology resident from 1989 to 1990. Dr. Ptáček then became the Muscular Dystrophy Association Neuromuscular Fellow at University of Utah's department of human genetics in 1990, and from 1991 to 1994 he completed postdoctoral work in molecular biology in Ray White's laboratory at the University of Utah. In 1992 Dr. Ptáček became an assistant professor in the department of neurology at the University of Utah, and he was the director of the division of neurogenetics from 2000 to 2003. In 2003 he joined the University of California, San Francisco, as John C. Coleman Distinguished Professor of Neurology and director of the division of neurogenetics there. Dr. Ptáček has been an investigator in the Howard Hughes Medical Institute since 2003. He is a fellow of the American Academy of Neurology, and a member of the Institute of Medicine at the National Academies of Science, the American Academy of Arts and Sciences, the American Association of Physicians and the National Academy of Science. He was given the University of Utah's Golden Anniversary Prize for Distinguished Clinical Investigation, the Derek Denny-Brown Neurological Scholar Award from the American Neurological Association and the Bauer Foundation Distinguished Professor award from Brandeis University.

Open to

Public

Reception

Refreshments, 3:45 p.m. - 4:00 p.m., Lower Level Greenberg Building (CRC)

Contact

Jill Benz

Phone

(212) 327-7244

Sponsor

Jill Benz
(212) 327-7244
benzj@rockefeller.edu