The Meyer-Bernstein Lab
MOLECULAR ANALYSIS OF CIRCADIAN RHYTHMS
Elizabeth Meyer-Bernstein
Ph.D.,
SUNY Stony Brook, 1998
Assistant Professor of Biology
Department of Biology
College of Charleston
66 George Street
Charleston, SC 29424
Office: Rita Liddy Hollings Science Center, Rm 233
Email: meyerbernsteine@cofc.edu
Phone: 843-953-2298
Fax: 843-953-5453
The research goal of Dr. Meyer-Bernstein is to understand how the circadian clock regulates the timing of behavioral and biological processes at the molecular level.
Current Research
We now know that mechanisms underlying overt rhythms are conserved across species. Despite recent advances in circadian research, molecular mechanisms underlying clock function are not completely understood. In particular, we know little about the how the clock molecules and cells communicate to regulate overt rhythms. Furthermore, the precise mechanism underlying the ability of light and other signals to synchronize the clock are unknown. Dr. Meyer-Bernstein’s research plan is designed to gain insights into these processes using both the fruit fly, Drosophila melanogaster, and the mouse, mus musculus, as model systems. Human ailments such as Alzheimer’s disease, bipolar disorder, seasonal affective disorder and various sleep disorders have been linked to aberrant clock function. In addition, this research directly impacts quality of life and safety issues associated with jet lag and shift work.
One goal in the lab is to further develop the model in Drosophila melanogaster by A) elucidating the precise molecular mechanism by which the TIM/NORPA interaction controls the visual sensitivity rhythm, and B) evaluating the significance of the retinal rhythm with regards to light responsiveness of circadian behavioral rhythms.
Although the phospholipase C (PLC) story in Drosophila is far from complete, evidence suggests this enzyme may function in the mammalian circadian system as well. Although mammals do not use the PLC pathway for visual transduction, rat phospholipase synthesis, rat PLC activity and chick phospholipid metabolism all exhibit a circadian oscillation in the retina. In addition, the mammalian homolog of NORPA, PLCb4, is not only found in the circadian clock of the mouse, but appears important for rhythmic electrical output of the clock cells. The retinal release of pituitary adenylate cyclase activating polypeptide in the mammalian clock also results in a PLC-dependent increase in calcium. Furthermore, it has recently been demonstrated that although mice lacking PLCb4 can successfully synchronize their activity to a light:dark cycle, in the absence of this input (constant darkness), the animals are arrhythmic. This is consistent with some Drosophila norpA mutants that also exhibit arrhythmic behavior in the dark (Meyer-Bernstein, unpublished data).
Taken together, these data strongly suggest a role for PLC in the mammalian circadian system. Because of NORPA’s role as an output molecule in the Drosophila retina, Meyer-Bernstein proposes PLCb4 may have a similar function in both the retina and clock cells in the mouse. A second aim of the current research is to identify a role for phospholipases and associated signaling molecules in the mammalian circadian system.
Lab Students
Past Lab Members (click photos to enlarge)
Travis Jenkins (’05):
Travis Jenkins (2004-2006) Bachelor’s Essay: Role of G-protein
signaling molecules in the mouse circadian system. Travis graduated
in May 2005 with a BS in Marine Biology/Biology and a minor in Chemistry.
He continued as a technician for one year in the lab. Travis is currently
attending New York Medical College in Valhalla, New York where he is planning
to pursue an MD/PhD in Neurology.
Rich Wooldridge (’06):
Rich Wooldridge (2005-2006). Bachelor’s Essay: Differential roles for phospholipase Cb isoforms
in the mammalian circadian system. Rich graduated in May 2006 with
a BS in Biology and a minor in Chemistry. He is currently employed at
National Integrated Health Associates in Baltimore, Maryland. He plans
to apply to medical school this coming year.
Sarah Belden (’06):
Sarah Belden (2005-2006). Bachelor’s Essay: Distribution of period gene
in behaviorally split hamster brains. Sarah graduated in May 2006 with a
BS in Biology and a minor in Spanish. She is applying to graduate school to become
a Physician’s Assistant.
Current Lab Members
Barbra Bannan (’07):
Barbra is a senior and has been conducting research in the laboratory
on molecular mechanisms underlying the biological clock in the liver since the
Spring 2006 term. She continued in the lab over the summer for which she received
additional funding from the SURF program and is currently conducting a Bachelor’s
Essay in the laboratory. Her project is now taking a new focus and that is to
understand the intracellular signals underlying the ability of light to reset
the biological clock. She will be graduating in May 2007 with a BS in Biology.
Post-graduation, Barbra plans to continue laboratory research for a year while
applying to medical school. Her ultimate goal is to become a surgeon. Barbra
wanted to take the opportunity to do undergraduate research in order to lean
more about various laboratory techniques as well as gain a better understanding
of physiology.
Blakely Andrews (’07):
Blakely is a senior and began her research project in the summer
of 2006 looking at the biological clock cells in the brain and the intracellular
signaling proteins that are localized there. She continues her work as a Bachelor’s
Essay on cellular signaling molecules in the biological clock of the liver. She
will be graduating in May 2007 with a BS in Biology with an emphasis in Molecular
Biology and a minor in Studio Art. In fall 2007, she will be attending medical
school at MUSC, in hopes of becoming a family practitioner. Blakely became interested
in working the laboratory for the chance to use the knowledge she has gained
in her biology classes in a practical setting with potential human applications.
Brittany Klein (’07):
Brittany is a senior and began working in the laboratory
in the summer of 2006. She was interested in experiencing the daily
workings of an undergraduate laboratory that produces current findings in the
field of neuroscience. Her project investigates the regulation of the gene
expression of a cell signaling enzyme in the biological clocks in both liver
and brain tissue. She continues her work as a Bachelor’s Essay and will
be graduating in May 2007 with a BS in Biology. She plans to continue research
in Charleston, SC for a year post-graduation while applying to medical school.
She is interested in specializing in neurology or internal medicine.
Andrea Chianella (’08):
Andrea is currently a junior at the College of
Charleston. She began working in the laboratory in the Fall 2006 semester.
She plans on graduating in May 2008 with a BS in biology with the
ultimate goal of attending medical school. She says, “the skills and knowledge
I have attained through hands-on-research in the lab will follow me
throughout school, and continue into my professional career. This
opportunity is one of the highlights of my undergraduate academic
studies.”
Incoming Lab Members
David Williams (’08):
David Williams will start in the spring 2007 semester. He is currently
a junior and majoring in Biology.