Logo for University of Iowa Health Care This logo represents the University of Iowa Health Care

Sheila A. Baker, PhD

Associate Professor of Ophthalmology and Visual Sciences
Associate Professor of Biochemistry

Contact Information

4-712 Bowen Science Building (BSB)
Iowa City, IA 52242

Iowa City, IA 52242


BS, Biology, University of Wisconsin
PhD, Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin
Post Graduate, Ophthalmology, Duke University School of Medicine

Education/Training Program Affiliations

Department of Biochemistry PhD, Interdisciplinary Graduate Program in Molecular Medicine, 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.


Lankford, C. K., Laird, J. G., Inamdar, S. M. & Baker, S. A. (2020). A Comparison of the Primary Sensory Neurons Used in Olfaction and Vision. Front Cell Neurosci., 14. PMID: 33250719.

Maddox, J. W., Randall, K. L., Yadav, R. P., Williams, B., Hagen, J., Derr, P. J., Kerov, V., Della, S. L., Baker, S. A., Artemyev, N., Hoon, M. & Lee, A. (2020). A dual role for Cav1.4 Ca2+ channels in the molecular and structural organization of the rod photoreceptor synapse. Elife, 9. PMID: 32940604.

Laird, J., Gardner, S., Kopel, A., Kerov, V., Lee, A. & Baker, S. (2019). Rescue rod synapses by induction of Cav alpha 1F in the mature Cav1.4 knock-out mouse retina. Invest Ophthalmol Vis Sci, 60(8), 3150-3161.

Kerov, V., Laird, J., Joiner, M., Knecht, S., Soh, D., Hagen, J., Gardner, S., Gutierrez, W., Yoshimatsu, T., Bhattarai, S., Puthussery, T., Artemyev, N., Drack, A., Wong, R., Baker, S. & Lee, A. (2018). a2d-4 Is Required for the Molecular and Structural Organization of Rod and Cone Photoreceptor Synapses. J. Neuroscience, 38(27), 6145-6160. PMID: 29875267.

Inamdar, S., Lankford, C., Laird, J., Novbatova, G., Tatro, N., Whitmore, S., Scheetz, T. & Baker, S. (2018). Analysis of 14-3-3 isoforms expressed in photoreceptors. Exp Eye Res., 170, 108-116. PMID: 29486162.

Schaefer, K., Toral, M., Velex, G., Cox, A., Baker, S. A., Borcherding, N., Colgan, D., Bondada, V., Mashburn, C., Yu, C., Geddes, J., Tsang, S., Bassuk, A. & Mahajan, V. (2016). Calpain-5 expression in the retina localizes to photoreceptor synapses. Invest Ophthalmol Vis Sci, 57(6), 2509-2521.

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., 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.

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., 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.

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.

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.

Dieck, T. S. (2013). Keeping The Balance. (Vols. 7). (6), pp. 418-419. Channels.

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.

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.

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.

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). Photoreceptors and Intraflagellar Transport. Recent Advances in Human Biology. pp. 109-132. Photoreceptor Cell Biology and Inherited Retinal Degenerations.

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.

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.

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.