Nicholas Ryba, Ph.D.
Laboratory of Sensory Biology
Building 49, Room 1A16
49 Convent Drive
Bethesda, MD 20892
Our senses provide us with a faithful internal representation of the external world. We are interested in basic questions of sensory perception and have focused on the chemical senses, taste and smell, as powerful models to explore how sensory signals are detected and distinguished.
Olfaction provides animals with a broad sensory experience: we can distinguish a remarkable number of distinct odors, most of which have no intrinsic meaning or valance. Over the past 20 years the field of olfaction has been dominated by Linda Buck and Richard Axel's discovery of a vast family of odorant receptors (~ 3 % of mouse genes encode odorant receptors). Recently, we have been generating mouse models with altered odorant receptor expression and examining fundamental questions concerning how this influences gene choice, circuit wiring and olfactory function. Some of this work has been carried out in collaboration with Leo Belluscio, NINDS.
The sense of taste has a much more specialized function than olfaction and serves as a dominant regulator and driver of feeding behavior. The taste system categorizes diverse chemical stimuli into just a handful of distinct perceptual qualities (e.g. sweet, bitter, sour, salty, and the savory taste, umami). This limited palette of taste qualities provides animals with valuable information about whether to consume or reject a particular item of food or drink and most probably evolved in this form to facilitate such binary decisions.
Over the past 15 years, in a wonderful collaborative research effort with Charles Zuker, HHMI, Columbia University, we have identified the taste receptors for sweet, bitter, salty and savory stimuli and the logic of coding for all five distinct taste qualities at the periphery in mice. These studies have revealed that each taste quality is encoded by activation of a specific and distinct population of taste receptor cells that are hardwired to trigger the appropriate behavioral response. Identification of selective markers of each class of taste receptor cell provides a powerful approach to mark the cells, define the corresponding signaling pathways and to begin to trace and functionally manipulate the respective neuronal connectivity circuits. Our current work is largely focused on understanding how detection leads to perception. We are using a combination of mouse behavioral paradigms, molecular-genetic and viral based gene delivery platforms, together with electrophysiological and functional imaging approaches to study how taste receptor cell stimulation is transmitted to the brain and encoded there. Ultimately we hope to help uncover how simple stimuli like sugar reliably generate a complex perceptual quality like sweetness and how taste input combines with other sensory modalities (e.g. olfaction and somatosensation) as well as internal state (e.g. hunger, satiety, etc.) to pattern behavior.
Nick Ryba received his degrees in biochemistry (B.A., 1982 and D. Phil., 1986) from Oxford University, Oxford, UK. He completed post-doctoral training at the Max-Planck-Institut-für-biophysikalishe-Chemie in Göttingen, Germany and the University of Leeds, UK under the guidance of Drs. Derek Marsh and John Findlay. In 1991, he joined NIDR (now NIDCR) to establish an independent group studying the molecular and cellular mechanisms underlying the perception of taste and smell. He now heads the Laboratory of Sensory Biology, NIDCR and his section focuses primarily on understanding the biology of taste but also retains a keen interest in the sense of smell.
Nguyen MQ, Wu Y, Bonilla LS, von Buchholtz LJ, Ryba NJP. Diversity amongst trigeminal neurons revealed by high throughput single cell sequencing. PLoS One. 2017;12(9):e0185543.
Wang L, Gillis-Smith S, Peng Y, Zhang J, Chen X, Salzman CD, Ryba NJP, Zuker CS. The coding of valence and identity in the mammalian taste system. Nature. 2018;558(7708):127-131.
Lee H, Macpherson LJ, Parada CA, Zuker CS, Ryba NJP. Rewiring the taste system. Nature. 2017;548(7667):330-333.
Peng Y, Gillis-Smith S, Jin H, Tränkner D, Ryba NJ, Zuker CS. Sweet and bitter taste in the brain of awake behaving animals. Nature. 2015;527(7579):512-5.
Barretto RP, Gillis-Smith S, Chandrashekar J, Yarmolinsky DA, Schnitzer MJ, Ryba NJ, Zuker CS. The neural representation of taste quality at the periphery. Nature. 2015;517(7534):373-6.
Related Scientific Focus Areas
Molecular Biology and Biochemistry
This page was last updated on September 9th, 2018