Sheila A. Baker, PhD

Associate Professor of Biochemistry
Associate Professor of Ophthalmology and Visual Sciences

Contact Information

Primary Office: 4-712 BSB
Iowa City, IA 52242

Lab: 4-712 BSB
Iowa City, IA 52242


BS, Biology, University of Wisconsin, Stevens Point
PhD, Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin

Post Doctoral Fellow, Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School
Post Doctoral Fellow, Ophthalmology, Albert Eye Research Institute, Duke University

Education/Training Program Affiliations

Department of Biochemistry PhD, Interdisciplinary Graduate Program in Molecular and Cellular Biology, Interdisciplinary Graduate Program in Neuroscience, Medical Scientist Training Program

Center, Program and Institute Affiliations

Institute for Vision Research, Iowa Neuroscience Institute

Research Summary

Our vision has such a large dynamic range that we can adjust to see under the glaring light of high noon to traverse a desert or detect the small scattering of photons that reach our eye after traveling for 2.5 million light-years from the Andromeda Galaxy. How is this possible? One part of the answer to that question lies in the cellular organization of our photoreceptors where a division of labor ensures optimal function. The phototransduction cascade, one of the best studied G-protein signaling pathways, is confined to the membrane discs of the outer segment; while energy production, metabolism, lipid and protein synthesis are confined to the inner segment. Distinct from the outer or inner segment, the ribbon synapse is where communication to downstream neurons in the retina is regulated. We study how various proteins are trafficked to, and organized within, these compartments using mouse or frog photoreceptors as our model systems. By gaining insight into the interplay between the regulated trafficking of different proteins and the development and health of photoreceptors the vision research community will be better positioned to combat blindness. Please contact us if you have questions about our current projects.


(2016). Calpain-5 expression in the retina localizes to photoreceptor synapses. Invest Ophthalmol Vis Sci, 57(6), 2509-2521.

Pan, Y., Laird, J. G., Yamaguchi, D. M. & Baker, S. A. (2015). A di-arginine ER retention signal regulates trafficking of HCN1 channels from the early secretory pathway to the plasma membrane. Cellular and molecular life sciences: CMLS, 72(4), 833-843. PMID: 25142030.

Pan, Y., Laird, J. G., Yamaguchi, D. M. & Baker, S. A. (2015). An N-Terminal ER Export Signal Facilitates the Plasma Membrane Targeting of HCN1 Channels in Photoreceptors. Investigative ophthalmology & visual science, 56(6), 3514-21. PMID: 26030105.

Laird, J. G., Pan, Y., Modestou, M., Yamaguchi, D. M., Song, H., Sokolov, M. & Baker, S. A. (2015). Identification of a VxP Targeting Signal in the Flagellar Na+ /K+ -ATPase. Traffic (Copenhagen, Denmark), 16(12), 1239-1253. PMID: 26373354.

Cao, Y., Sarria, I., Fehlhaber, K. E., Kamasawa, N., Orlandi, C., James, K. N., Hazen, J. L., Gardner, M. R., Farzan, M., Lee, A., Baker, S., Baldwin, K., Sampath, A. P. & Martemyanov, K. A. (2015). Mechanism for Selective Synaptic Wiring of Rod Photoreceptors into the Retinal Circuitry and Its Role in Vision. Neuron, 87(6), 1248-60. PMID: 26402607.

Pan, Y., Bhattarai, S., Modesto, M., Drack, A. V., Chetkovich, D. M. & Baker, S. A. (2014). TRIP8b is required for maximal expression of HCN1 in the mouse retina. PLoS One, 9(1), e850850. PMID: 24409334.

Pearring, J. N., Lieu, E. C., Winter, J. R., Baker, S. A. & Arshavsky, V. Y. (2014). R9AP targeting to rod outer segments is independent of rhodopsin and is guided by the SNARE homology domain. Mol Biol Cell, 25(17), 2644-9. PMID: 25009288.

Pearring, J. N., Salinas, R. Y., Baker, S. A. & Arshavsky, V. Y. (2013). Protein sorting, targeting and trafficking in photoreceptor cells. Progress in retinal and eye research. PMID: 23562855.

Salinas, R. Y., Baker, S. A., Gospe, S. M. & Arshavsky, V. Y. (2013). A single valine residue plays an essential role in peripherin/rds targeting to photoreceptor outer segments. PloS one, 8(1), e54292. PMID: 23342122.

Baker, S. A., Kerov, V. (2013). Photoreceptor inner and outer segments. pp. 231-65. Curr Top Membr. PMID: 24210432.

Liu, X., Kerov, V., Haeseleer, F., Artemyev, N., Baker, S. A. & Lee, A. (2013). Dysregulation of Cav 1.4 channels disrupts the maturation of photoreceptor synaptic ribbons in congenital stationary night blindness type 2. Channels (Austin), 7(6). PMID: 24064553.

Knoflach, D., Kerov, V., Satori, G. B., Obermair, G. J., Schmuckermair, C., Liu, X., Sothilingam, V., Garrido, M. G., Baker, S. A., Glosmann, M., Schicker, K., Seeliger, M., Lee, A. & Koschak, A. (2013). Cav1.4 IT mouse as model for vision impairment in human congenital stationary night blindness type 2. Channels (Austin), 7(6). PMID: 24051672.

Gospe, S. M., Baker, S. A., Kessler, C., Brucato, M. F., Winter, J. R., Burns, M. E. & Arshavsky, V. Y. (2011). Membrane attachment is key to protecting transducin GTPase-activating complex from intracellular proteolysis in photoreceptors. The Journal of neuroscience : the official journal of the Society for Neuroscience, 31(41), 14660-8. PMID: 21994382.

Gospe, S. M., Baker, S. A. & Arshavsky, V. Y. (2010). Facilitative glucose transporter Glut1 is actively excluded from rod outer segments. Journal of cell science, 123(21), 3639-44. PMID: 20923839.

Kizhatil, K., Baker, S. A., Arshavsky, V. Y. & Bennett, V. (2009). Ankyrin-G promotes cyclic nucleotide-gated channel transport to rod photoreceptor sensory cilia. Science (New York, N.Y.), 323(5921), 1614-7. PMID: 19299621.

Bhowmick, R., Li, M., Sun, J., Baker, S. A., Insinna, C. & Besharse, J. C. (2009). Photoreceptor IFT complexes containing chaperones, guanylyl cyclase 1 and rhodopsin. Traffic (Copenhagen, Denmark), 10(6), 648-63. PMID: 19302411.

Baker, S. A., Haeri, M., Yoo, P., Gospe, S. M., Skiba, N. P., Knox, B. E. & Arshavsky, V. Y. (2008). The outer segment serves as a default destination for the trafficking of membrane proteins in photoreceptors. The Journal of cell biology, 183(3), 485-98. PMID: 18981232.

Luby-Phelps, K., Fogerty, J., Baker, S. A., Pazour, G. J. & Besharse, J. C. (2008). Spatial distribution of intraflagellar transport proteins in vertebrate photoreceptors. Vision research, 48(3), 413-23. PMID: 17931679.

Baker, S. A., Martemyanov, K. A., Shavkunov, A. S. & Arshavsky, V. Y. (2006). Kinetic mechanism of RGS9-1 potentiation by R9AP. Biochemistry, 45(35), 10690-7. PMID: 16939221.

Baker, S. A., Pazour, G. J., Witman, G. B. & Besharse, J. C. (2004). Protoreceptors and Intraflagellar Transport. Recent Advances in Human Biology. pp. 109-132. Photoreceptor Cell Biology and Inherited Retinal Degenerations.

Besharse, J. C., Baker, S. A., Luby-Phelps, K. & Pazour, G. J. (2003). Photoreceptor intersegmental transport and retinal degeneration: a conserved pathway common to motile and sensory cilia. pp. 157-64. Advances in experimental medicine and biology. PMID: 15180260.

Baker, S. A., Freeman, K., Luby-Phelps, K., Pazour, G. J. & Besharse, J. C. (2003). IFT20 links kinesin II with a mammalian intraflagellar transport complex that is conserved in motile flagella and sensory cilia. Journal of Biological Chemistry, 278(36), 34211-8. PMID: 12821668.

Pazour, G. J., Baker, S. A., Deane, J. A., Cole, D. G., Dickert, B. L., Rosenbaum, J. L., Witman, G. B. & Besharse, J. C. (2002). The intraflagellar transport protein, IFT88, is essential for vertebrate photoreceptor assembly and maintenance. The Journal of cell biology, 157(1), 103-13. PMID: 11916979.

McBride, M. J., Baker, S. A. (1996). Development of techniques to genetically manipulate members of the genera Cytophaga, Flavobacterium, Flexibacter, and Sporocytophaga. Applied and environmental microbiology, 62(8), 3017-22. PMID: 8702294.