Every moment, organisms must make behavioral decisions that optimize survival and fitness based on internal state cues and external environmental cues. The Barber Lab focuses on key survival behaviors driven by a protohypothalamic region in the fly brain called the pars intercerebralis. How do neurons within the pars intercerebralis sense internal state cues like hunger, tiredness and time of day? How do neurons within the pars intercerebralis sense environmental cues like food availability and taste? And finally, when multiple conflicting cues arrive in the brain, how are signals integrated to allow the fly to select from mutually exclusive behaviors?
Untangling neuropeptide and fast neurotransmitter signaling in a defined circuit
Neural circuits use a combination of classical fast neurotransmitters and modulatory peptide neurotransmitters to communicate. The clock circuit uses both types of signals to influence the circadian timing of sleep, feeding and locomotion. This project will use a combination of behavioral genetics and classical biochemical methods to understand how the circadian clock uses signals to output brain regions that drive locomotor and feeding behavior.
Integration of internal state and external environmental cues at the circuit level
Organisms must make behavioral decisions based on an array of both internal state cues (like hunger or time of day) and external environmental cues (like availability of food or temperature). The Drosophila pars intercerebralis is a “hub” brain region that receives information about both state and environmental cues, and then releases an array of neuropeptides that influence fly behavior. This project will investigate how diverse signals integrate within the PI at the molecular and electrophysiological level to influence behavioral choice.
Now recruiting graduate and postdocs.
If you’re interested in understanding the biological basis of complex behaviors at the molecular, cellular and circuit levels - join us! Email firstname.lastname@example.org for details.
Waksman Institute of Microbiology
190 Frelinghuysen Road
Piscataway, NJ 08854
Sleep signals are integrated into an output arm of the circadian clock.
King AN, Barber AF, Schwarz J and Sehgal A. Sleep signals are integrated into an output arm of the circadian clock. In Preparation.
Monitoring electrical activity in Drosophila circadian output neurons.
Barber AF and Sehgal A. Monitoring electrical activity in Drosophila circadian output neurons. Methods Mol Biol Invited review, in press. Cell Metabolism 27: 951-953
Preview: Cold temperatures fire up circadian neurons.
Barber AF and Sehgal A. (2018) Preview: Cold temperatures fire up circadian neurons.
A peptidergic circuit links the circadian clock to locomotor activity.
King AN, Barber AF, Smith AE, Dreyer AP, Sitaraman D, Nitabach MN, Cavanaugh DJ, & Sehgal A. (2017). A peptidergic circuit links the circadian clock to locomotor activity. Curr Biol 27: 1915-27
ircadian and feeding cues integrate to drive rhythms of physiology in Drosophila insulin producing cells.
Barber AF, Erion R, Holmes TC and Sehgal A. (2016). Circadian and feeding cues integrate to drive rhythms of physiology in Drosophila insulin producing cells. Genes Dev 30: 2596-2606
Mechanistic Insights into the Modulation of Voltage-Gated Ion Channels by Inhalational Anesthetics
Covarrubias M, Barber AF, Carnevale V, Treptow W, and Eckenhoff, RG. (2015) Mechanistic Insights into the Modulation of Voltage-Gated Ion Channels by Inhalational Anesthetics Biophys J 109: 2003-11
Modulation of a voltage-gated Na+ channel by sevoflurane involves multiple sites and distinct mechanisms.
Barber AF, Carnevale V, Klein ML, Eckenhoff RG, and Covarrubias M. (2014) Modulation of a voltage-gated Na+ channel by sevoflurane involves multiple sites and distinct mechanisms. Proc Natl Acad Sci USA 111: 6726-31
Exploring Volatile General Anesthetic Binding to a Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel via Computation
Raju SG, Barber AF, Lebard DN, Klein ML and Carnevale V. (2013) Exploring Volatile General Anesthetic Binding to a Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel via Computation. PLOS Comput Biol 9: e1003090
Hinge-bending motions in the pore domain of a bacterial voltage-gated sodium channel.
Barber AF, Carnevale V, Raju SG, Amaral C, Treptow W and Klein ML (2012) Hinge-bending motions in the pore domain of a bacterial voltage-gated sodium channel. BBA Biomembranes 1818: 2120-25.
Novel activation of voltage gated K+ channels by sevoflurane.
Barber AF, Liang Q, Covarrubias M. (2012) Novel activation of voltage gated K+ channels by sevoflurane. J Biol Chem 287: 40425-32
Molecular mapping of general anesthetic sites in a voltage-gated ion channel.
Barber AF, Liang Q, Amaral C, Treptow W and Covarrubias M. (2011) Molecular mapping of general anesthetic sites in a voltage-gated ion channel. Biophys J 101:1613-22
Dr. Annika Barber
Dr. Annika Barber is an Assistant Professor in the Department of Molecular Biology and Biochemistry and a laboratory director at the Waksman Institute beginning January 2020. Dr. Barber uses the fruit fly, Drosophila melanogaster, to investigate how neuropeptide signaling is involved in integrating a myriad of sensory cues to select behavioral programs. Her work integrates genetics, behavior and neurophysiology.
Dr. Barber got her Bachelor of Science at Bryn Athyn College. She did her doctoral work at Thomas Jefferson University with Manuel Covarrubias, mapping binding sites for inhaled anesthetics in voltage gated ion channels and developing Markov models of how anesthetics impair channel gating. Dr. Barber moved from single cell patch clamp electrophysiology to Drosophila behavior when she started her Postdoctoral Fellowship with Amita Sehgal at the University of Pennsylvania. In her postdoc, Dr. Barber investigated how a circadian output region regulates sleep, feeding and metabolic function. This piqued her interest in understanding the complex interplay of neuropeptides in Drosophila behavioral circuitry.