Steven Andrew Barnes
Professor-in-Residence, Ophthalmology, University of California Los Angeles
Professor-in-Residence, Neurobiology, University of California Los Angeles
The neuronal circuits of the retina are the part of the eye that my laboratory studies. We are investigating how and why photoreceptors, horizontal cells, bipolar cells, amacrine cells and ganglion cells shape and tune their electrical signals using membrane ion channels, and how they transfer these signals to one another using chemical neurotransmitter synapses. We work on how the retinal neurons detect spatial and color contrast in visual space and respond to temporal changes in light intensity, how newly generated neurons develop proper retinal properties when grown from stem cells in a dish, and how the different retinal metabolic environments affect the signaling and well-being of their neurons. Our current work is undertaken in collaboration with other laboratories at the Doheny Eye Institute and UCLA’s Stein Institute, along with the Departments of Ophthalmology and Neurobiology.
Dr. Steven Barnes a Professor in the Departments of Ophthalmology and Neurobiology at UCLA, based at the Doheny Eye Institute. His retinal neurobiology lab studies the function of cells and synapses in the retina, integrating this knowledge with the emerging impact that retinal diseases, such as glaucoma and macular degeneration, have on retinal cell activity and vision due to disrupted metabolic function. Prior to joining UCLA and the Doheny Eye Institute in 2018, Dr. Barnes had been a Professor of Physiology & Biophysics at Dalhousie University in Nova Scotia, Canada for 20 years. Before that, he was Assistant and then Associate Professor at the University of Calgary in Alberta, Canada. Born in Vancouver, British Columbia, he received his Ph.D. in Neurobiology from UC Berkeley under Frank Werblin and did postdoctoral training with Bertil Hille at the University of Washington in Seattle.
- Smith BJ, McHugh CF, Hirano AA, Brecha NC, Barnes S. Transient and Sustained Ganglion Cell Light Responses Are Differentially Modulated by Intrinsically Produced Reactive Oxygen Species Acting upon Specific Voltage-Gated Na+ Channel Isoforms.. The Journal of neuroscience : the official journal of the Society for Neuroscience, 2023.
- Barnes S. Visual processing: When two synaptic strata are better than one.. Current biology : CB, 2022.
- Zhang X, Mandric I, Nguyen KH, Nguyen TTT, Pellegrini M, Grove JCR, Barnes S, Yang XJ. Single Cell Transcriptomic Analyses Reveal the Impact of bHLH Factors on Human Retinal Organoid Development.. Frontiers in cell and developmental biology, 2021.
- Hirano AA, Vuong HE, Kornmann HL, Schietroma C, Stella SL, Barnes S, Brecha NC. Vesicular Release of GABA by Mammalian Horizontal Cells Mediates Inhibitory Output to Photoreceptors.. Frontiers in cellular neuroscience, 2020.
- Grove JCR, Hirano AA, de Los Santos J, McHugh CF, Purohit S, Field GD, Brecha NC, Barnes S. Novel hybrid action of GABA mediates inhibitory feedback in the mammalian retina.. PLoS biology, 2019.
- Hirano AA, Liu X, Brecha NC, Barnes S. Analysis of Feedback Signaling from Horizontal Cells to Photoreceptors in Mice.. Methods in molecular biology (Clifton, N.J.), 2018.
- Sun X, Hirano AA, Brecha NC, Barnes S. Calcium-activated BKCa channels govern dynamic membrane depolarizations of horizontal cells in rodent retina.. The Journal of physiology, 2017.
- Matynia A, Nguyen E, Sun X, Blixt FW, Parikh S, Kessler J, Pérez de Sevilla Müller L, Habib S, Kim P, Wang ZZ, Rodriguez A, Charles A, Nusinowitz S, Edvinsson L, Barnes S, Brecha NC, Gorin MB. Peripheral Sensory Neurons Expressing Melanopsin Respond to Light.. Frontiers in neural circuits, 2016.
- Liu X, Grove JC, Hirano AA, Brecha NC, Barnes S. Dopamine D1 receptor modulation of calcium channel currents in horizontal cells of mouse retina.. Journal of neurophysiology, 2016.
- Hirano AA, Liu X, Boulter J, Grove J, Pérez de Sevilla Müller L, Barnes S, Brecha NC. Targeted Deletion of Vesicular GABA Transporter from Retinal Horizontal Cells Eliminates Feedback Modulation of Photoreceptor Calcium Channels.. eNeuro, 2016.
- Vuong HE, Hardi CN, Barnes S, Brecha NC. Parallel Inhibition of Dopamine Amacrine Cells and Intrinsically Photosensitive Retinal Ganglion Cells in a Non-Image-Forming Visual Circuit of the Mouse Retina.. The Journal of neuroscience : the official journal of the Society for Neuroscience, 2015.
- Sargoy A, Barnes S, Brecha NC, Pérez De Sevilla Müller L. Immunohistochemical and calcium imaging methods in wholemount rat retina.. Journal of visualized experiments : JoVE, 2014.
- Sargoy A, Sun X, Barnes S, Brecha NC. Differential calcium signaling mediated by voltage-gated calcium channels in rat retinal ganglion cells and their unmyelinated axons.. PloS one, 2014.
- Liu X, Hirano AA, Sun X, Brecha NC, Barnes S. Calcium channels in rat horizontal cells regulate feedback inhibition of photoreceptors through an unconventional GABA- and pH-sensitive mechanism.. The Journal of physiology, 2013.