Steven M. Reppert
Encyclopedia
Steven M. Reppert is an American
neuroscientist
who has made seminal contributions to the field of circadian biology over the last three decades. His research has focused largely on the physiological, cellular, and molecular basis of circadian rhythms in mammals and more recently on circadian clock mechanisms in the monarch butterfly
. He is currently the founding chair of the Department of Neurobiology and the Higgins Family Professor of Neuroscience at the University of Massachusetts Medical School
.
and was elected as a medical student to the Alpha Omega Alpha Honor Medical Society. He did an internship and residency in Pediatrics at the Massachusetts General Hospital
and postdoctoral work in neuroendocrinology at the National Institute of Child Health and Human Development
in Bethesda, Maryland with David C. Klein. Reppert was on the faculty at the Massachusetts General Hospital and Harvard Medical School
beginning in 1979 and was promoted to Professor in 1993; he directed the Laboratory of Developmental Chronobiology at the Massachusetts General Hospital from 1983 to 2001, when he moved to the University of Massachusetts Medical School.
Reppert was a Charles King Trust Research Fellow from 1981 to 1983 and an Established Investigator of the American Heart Association
from 1985 to 1990. He has been a recipient of the E. Mead Johnson Award
for Outstanding Research Contributions (1989) and the NIH-NICHD MERIT Award (1992–2002). From 2002 to 2004, he served as president of the Society for Research on Biological Rhythms. Reppert has published more than 150 papers in peer-reviewed journals and is the principal inventor on seven patents derived from his research.
(SCN), the site of the master brain clock, is cell autonomous (i.e., contained within single cells), and cloning and functionally defining a family of melatonin receptor
s (G-protein coupled receptors for the pineal hormone). Reppert’s group identified a molecular mechanism for regulating clock-controlled genes in mammals, discovered the function of cryptochrome
s within the mammalian circadian clock, and defined interlocking transcriptional feedback loops in the mouse SCN. In 2006, his team made the unexpected finding that CLOCK, a transcription factor believed to be an essential component of the molecular clockwork mechanism, is not necessary for SCN clock function. They went on to show that a related transcription factor, NPAS2 (MOP4), can functionally substitute for CLOCK in the SCN to regulate behavioral circadian rhythms.
Since 2002, Reppert and co-workers have pioneered study of the biological basis of monarch butterfly migration. They have focused on a novel circadian clock mechanism and its role in time-compensated sun compass orientation, a major navigational strategy the butterflies use during their fall migration. In recent work, his group has shown that antennae are necessary for this strategy, and that they house circadian clocks that function independent from the brain. His laboratory also provided the first genetic evidence that animal cryptochromes can function as light-dependent magnetoreceptors, which may be important for long-distance migration. Reppert’s group is currently sequencing and annotating the monarch butterfly genome to help understand the genetic basis of the migration.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
neuroscientist
Neuroscientist
A neuroscientist is an individual who studies the scientific field of neuroscience or any of its related sub-fields...
who has made seminal contributions to the field of circadian biology over the last three decades. His research has focused largely on the physiological, cellular, and molecular basis of circadian rhythms in mammals and more recently on circadian clock mechanisms in the monarch butterfly
Monarch butterfly
The Monarch butterfly is a milkweed butterfly , in the family Nymphalidae. It is perhaps the best known of all North American butterflies. Since the 19th century, it has been found in New Zealand, and in Australia since 1871 where it is called the Wanderer...
. He is currently the founding chair of the Department of Neurobiology and the Higgins Family Professor of Neuroscience at the University of Massachusetts Medical School
University of Massachusetts Medical School
The University of Massachusetts Medical School is one of five campuses of the University of Massachusetts system and is home to three schools: the School of Medicine, the Graduate School of Biomedical Sciences, the Graduate School of Nursing; a biomedical research enterprise; and a range of...
.
Background
Reppert received his BS and MD (with Distinction) from the University of Nebraska College of MedicineUniversity of Nebraska Medical Center
The University of Nebraska Medical Center is a public academic health sciences center located on 42nd and Emile Streets in Midtown Omaha, Nebraska. UNMC is the only public academic health science center in Nebraska.-Academics and rankings:...
and was elected as a medical student to the Alpha Omega Alpha Honor Medical Society. He did an internship and residency in Pediatrics at the Massachusetts General Hospital
Massachusetts General Hospital
Massachusetts General Hospital is a teaching hospital and biomedical research facility in the West End neighborhood of Boston, Massachusetts...
and postdoctoral work in neuroendocrinology at the National Institute of Child Health and Human Development
National Institute of Child Health and Human Development
The Eunice Kennedy Shriver National Institute of Child Health and Human Development , created by Congress in 1962, supports and conducts research on topics related to the health of children, adults, families, and populations...
in Bethesda, Maryland with David C. Klein. Reppert was on the faculty at the Massachusetts General Hospital and Harvard Medical School
Harvard Medical School
Harvard Medical School is the graduate medical school of Harvard University. It is located in the Longwood Medical Area of the Mission Hill neighborhood of Boston, Massachusetts....
beginning in 1979 and was promoted to Professor in 1993; he directed the Laboratory of Developmental Chronobiology at the Massachusetts General Hospital from 1983 to 2001, when he moved to the University of Massachusetts Medical School.
Reppert was a Charles King Trust Research Fellow from 1981 to 1983 and an Established Investigator of the American Heart Association
American Heart Association
The American Heart Association is a non-profit organization in the United States that fosters appropriate cardiac care in an effort to reduce disability and deaths caused by cardiovascular disease and stroke. It is headquartered in Dallas, Texas...
from 1985 to 1990. He has been a recipient of the E. Mead Johnson Award
E. Mead Johnson Award
The E. Mead Johnson Award, given by the Society for Pediatric Research, an affiliate of the American Pediatric Society, was established in 1939 to honor clinical and laboratory research achievements in pediatrics. Awards are funded by Mead Johnson Nutritionals, a subsidiary of Bristol-Myers Squibb....
for Outstanding Research Contributions (1989) and the NIH-NICHD MERIT Award (1992–2002). From 2002 to 2004, he served as president of the Society for Research on Biological Rhythms. Reppert has published more than 150 papers in peer-reviewed journals and is the principal inventor on seven patents derived from his research.
Research
The research contributions of Reppert and colleagues include defining the field of fetal circadian clocks, discovering that the circadian clock mechanism in the mammalian suprachiasmatic nucleusSuprachiasmatic nucleus
The suprachiasmatic nucleus or nuclei, abbreviated SCN, is a tiny region on the brain's midline, situated directly above the optic chiasm. It is responsible for controlling circadian rhythms...
(SCN), the site of the master brain clock, is cell autonomous (i.e., contained within single cells), and cloning and functionally defining a family of melatonin receptor
Melatonin receptor
A melatonin receptor is a G protein-coupled receptor which binds melatonin.Three types of melatonin receptor have been cloned. The MT1 and MT2 receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype MT3 has been identified in amphibia and...
s (G-protein coupled receptors for the pineal hormone). Reppert’s group identified a molecular mechanism for regulating clock-controlled genes in mammals, discovered the function of cryptochrome
Cryptochrome
Cryptochromes are a class of blue light-sensitive flavoproteins found in plants and animals. Cryptochromes are involved in the circadian rhythms of plants and animals, and in the sensing of magnetic fields in a number of species...
s within the mammalian circadian clock, and defined interlocking transcriptional feedback loops in the mouse SCN. In 2006, his team made the unexpected finding that CLOCK, a transcription factor believed to be an essential component of the molecular clockwork mechanism, is not necessary for SCN clock function. They went on to show that a related transcription factor, NPAS2 (MOP4), can functionally substitute for CLOCK in the SCN to regulate behavioral circadian rhythms.
Since 2002, Reppert and co-workers have pioneered study of the biological basis of monarch butterfly migration. They have focused on a novel circadian clock mechanism and its role in time-compensated sun compass orientation, a major navigational strategy the butterflies use during their fall migration. In recent work, his group has shown that antennae are necessary for this strategy, and that they house circadian clocks that function independent from the brain. His laboratory also provided the first genetic evidence that animal cryptochromes can function as light-dependent magnetoreceptors, which may be important for long-distance migration. Reppert’s group is currently sequencing and annotating the monarch butterfly genome to help understand the genetic basis of the migration.