Research 
How genes control animal behavior is the big question that my lab is interested in. We mainly study circadian (~24hr) rhythms of behavior which are the best understood behavior at the molecular level. We use the fruitfly Drosophila as a powerful model system that has led the way in circadian rhythm research and is ideal for analyzing behavior at multiple different levels: at the levels of single genes, single neurons and neuronal networks. We use genetics and genomics as well as microscopy of clock neurons as we aim to build a holistic model of how flies anticipate daily changes in the external environment. 
Adult flies have 24hr rhythms in their activity levels: they are more active by day, especially at dusk and dawn, and they rest by night – paralleling human sleep/wake cycles. These rhythms persist in constant darkness, indicating the existence of an internal clock. Forward genetics led to the identification of a number of clock genes that are essential for 24hr rhythms in constant darkness, and these genes work together to form two interlocked transcription / translation feedback loops (see figure 1). However, it is not clear how the ticking of this clock is translated into rhythms of clock neuron activity. This is one of the major questions that we are interested in and to answer this we have been developing a way to generate gene expression profiles from purified clock neurons.
Other projects ongoing in the lab include understanding molecular mechanisms of clock entrainment to the environment, interactions between clock neurons and identifying the neural circuits downstream of clock neurons that lead to behavior. Current lab members
Current funding NIH R01 GM063911 Teaching Main courses: I also teach in: BioCore II, Introduction to Cellular Neuroscience, Molecular & Cellular Biology Biosketch I graduated from Cambridge University with a BA in Natural Sciences in 1991. For my Ph.D., I worked with David Bentley at ICRF in London, studying the basic mechanisms of how transcription factors stimulate RNA polymerase II to activate gene expression. I decided to work on a larger and more open question while a postdoc, and joined Mike Young's laboratory in 1996 at The Rockefeller University in New York to work on circadian rhythms in Drosophila. I joined the faculty here at NYU as an Assistant Professor in 2000 and was awarded tenure in 2006. With time, I have become more interested in the neurobiology of the clock than in the details of the molecular clock feedback loops, and we are also becoming interested in whether Drosophila can be used as a simple model to study the neurobiology of decision-making. Areas of Research/Interest Molecular genetics of circadian rhythms in Drosophila Fellowships/Honors Norman and Rosita Winston Biomedical Research Foundation Fellowship, 1999-2000; Human Frontiers Science Program Long Term Fellowship, 1997-1999.
Publications
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We study the circadian neuronal network in Drosophila larvae in many of our experiments for two main reasons. First, there are less clock neurons in larvae compared to adults allowing the genetic manipulation of specific clock neuron subsets more precisely than in adults (figure 2). Second, the larval clock neurons regulate a rapid behavior – light avoidance by larvae. The clock neurons receive light information coming from the simple larval visual system and transmit it to downstream neurons. Their internal clock acts as a circadian filter for visual sensitivity, leading to a circadian rhythm in light avoidance (figure 3). This assay is proving useful to assay pacemaker neuron excitability (without using electrophysiology) and to understand how the molecular clock is linked to pacemaker neuron outputs.