Ignacio Provencio


  • PhD, University of Virginia
  • BA, Swarthmore College
  • Postdoc, Uniformed Services University

Primary Appointment

  • Associate Professor, Biology


Research Interest(s)

The Role of Melanopsin Retinal Ganglion Cells in the Photic Regulation of Mammalian Circadian Rhythms

Research Description

Light is critical for many biological processes. While vision is the most obvious of these, much of our "non-visual" physiology is regulated by light. For example, the internal 24-hour (circadian) clock that controls daily rhythms such as our sleep:wake cycle is reset by light. Responses that are controlled by the sympathetic system such as constriction of the eye's pupil, the production of the hormone melatonin, or even heart rate are all regulated by light to some degree. Many of these non-visual responses to light are controlled, at least in part, by a recently discovered class of photoreceptor in the retina.

Melanopsin is the photopigment within these novel photoreceptors that renders them light-sensitive. Our lab is interested in understanding the role that these melanopsin-based photoreceptors play in various non-visual responses to light. In addition, we are trying to elucidate the biochemical details of the signaling cascade that is initiated by melanopsin activation. We hope that these studies will illuminate the broader impact of light on vertebrate physiology.

Selected Publications

  • Aytürk D, Castrucci A, Carr D, Keller S, Provencio I. Lack of Melanopsin Is Associated with Extreme Weight Loss in Mice upon Dietary Challenge. PloS one. 2015;10(5): e0127031. PMID: 26011287 | PMCID: PMC4444252
  • Lucas R, Peirson S, Berson D, Brown T, Cooper H, Czeisler C, Figueiro M, Gamlin P, Lockley S, O'Hagan J, Price L, Provencio I, Skene D, Brainard G. Measuring and using light in the melanopsin age. Trends in neurosciences. 2013;37(1): 1-9. PMID: 24287308
  • Warthen D, Wiltgen B, Provencio I. Light enhances learned fear. Proceedings of the National Academy of Sciences of the United States of America. 2011;108(33): 13788-93. PMID: 21808002 | PMCID: PMC3158234
  • Shedding light on photoperiodism. Proceedings of the National Academy of Sciences of the United States of America. 2010;107(36): 15662-3. PMID: 20802157 | PMCID: PMC2936619
  • Berson D, Castrucci A, Provencio I. Morphology and mosaics of melanopsin-expressing retinal ganglion cell types in mice. The Journal of comparative neurology. 2010;518(13): 2405-22. PMID: 20503419 | PMCID: PMC2895505
  • Göz D, Studholme K, Lappi D, Rollag M, Provencio I, Morin L. Targeted destruction of photosensitive retinal ganglion cells with a saporin conjugate alters the effects of light on mouse circadian rhythms. PloS one. 2008;3(9): e3153. PMID: 18773079 | PMCID: PMC2519834
  • Roecklein K, Rohan K, Duncan W, Rollag M, Rosenthal N, Lipsky R, Provencio I. A missense variant (P10L) of the melanopsin (OPN4) gene in seasonal affective disorder. Journal of affective disorders. 2008;114(1): 279-85. PMID: 18804284 | PMCID: PMC2647333
  • Kumbalasiri T, Rollag M, Isoldi M, Castrucci A, Provencio I. Melanopsin triggers the release of internal calcium stores in response to light. Photochemistry and photobiology. 2006;83(2): 273-9. PMID: 16961436