Dr. John L. Spudich, Professor and Robert A. Welch Distinguished Chair in Chemistry

Director, Center for Membrane Biology
Department of Biochemistry and Molecular Biology
Program in Biochemistry and Molecular Biology

University of Texas-Houston Medical School
P.O. Box 20708 - Houston, Texas 77225
(713) 500-5473 fax:(713)500-0545
email: John.L.Spudich@uth.tmc.edu

Ph.D, University of California, Berkeley
Jane Coffin Childs Postdoctoral Fellow, Harvard Medical School
Fellow, American Academy of Arts & Sciences

membrane protein structure and function

The primary interest in our laboratory is the mechanism by which photosensory receptors sense and transmit information concerning the color, intensity, and pattern of light in the environment. We study a widespread class of photoactive receptor proteins (rhodopsins) that consist of seven transmembrane helices connected by interhelical loops. The helices form a pocket for the photosensitive molecule vitamin-A aldehyde (retinal), and the receptor proteins physically couple to protein transducers that relay signals to sensory pathways in the cytoplasm. These photosensitive heptahelical proteins are used for visual processes of various degrees of sophistication, ranging from detection of light-dark boundaries, light gradients, and light direction by single-cell microorganisms to high-resolution color image detection by higher animal eyes

Left: Sensory Rhodopsin II and its transducer, responsible for phototaxis signaling in haloarchaea. Middle: A cyanobacterial sensory rhodopsin of unknown function and its interacting partner (in Anabaena).
Right: ChR1, one of the channelrhodopsins that mediates phototaxis in eukaryotic algae. Channelrhodopsins have begun to be used extensively for photocontrol of neuronal activity in brain circuitry mapping and vision restoration experiments.

Sineshchekov OA, Govorunova EG, Spudich JL. Photosensory functions of channelrhodopsins in native algal cells. Photochem Photobiol. 85:556-563, 2009.

Bergo VB, Sineshchekov OA, Kralj JM, Partha R, Spudich EN, Rothschild KJ, Spudich JL. His-75 in proteorhodopsin, a novel component in light-driven proton translocation by primary pumps. J Biol Chem. 284:2836-2843, 2009.

Bergo VB, Spudich EN, Spudich JL, Rothschild KJ. Active water in protein-protein communication within the membrane: the case of SRII-HtrII signal relay. Biochemistry 48:811-813, 2009.

Spudich JL, Spudich EN “The Simplest Eyes: Rhodopsin-mediated Phototaxis Reception in Microorganisms”, in Animal Models in Eye Research (Ed: P.A. Tsonis; Elsevier Ltd., Amsterdam), pp. 6-14, 2008.

Sineshchekov OA, Sasaki J, Phillips BJ, Spudich JL. A Schiff base connectivity switch in sensory rhodopsin signaling. Proc Natl Acad Sci USA. 105:16159-16164, 2008.

Sasaki J, Nara T, Spudich EN, Spudich JL. Constitutive activity in chimeras and deletions localize sensory rhodopsin II/HtrII signal relay to the membrane-inserted domain. Mol Microbiol. 66:1321-1330, 2007.

Sasaki J, Phillips BJ, Chen X, Van Eps N, Tsai AL, Hubbell WL, Spudich JL. Different dark conformations function in color-sensitive photosignaling by the sensory rhodopsin I-HtrI complex. Biophys J. 92:4045-4053, 2007.

Vogeley L, Trivedi VD, Sineshchekov OA, Spudich EN, Spudich JL, Luecke H. Crystal structure of the Anabaena sensory rhodopsin transducer. J Mol Biol. 367:741-751, 2007.

Sudo, Y. and Spudich, J.L. Three strategically placed hydrogen-bonding residues convert a proton pump into a sensory receptor. Proc. Natl. Acad. Sci. USA 103, 16129-16134, 2006.

Sineshchekov OA, Spudich EN, Trivedi VD, Spudich JL. Role of the cytoplasmic domain in Anabaena sensory rhodopsin photocycling: vectoriality of Schiff base deprotonation. Biophys J. 91:4519-4527, 2006.

Sudo Y, Furutani Y, Kandori H, Spudich JL. Functional importance of the interhelical hydrogen bond between Thr204 and Tyr174 of sensory rhodopsin II and its alteration during the signaling process. J Biol Chem. 281:34239-34245, 2006.

Bergo VB, Ntefidou M, Trivedi VD, Amsden JJ, Kralj JM, Rothschild KJ, Spudich JL. Conformational changes in the photocycle of Anabaena sensory rhodopsin: absence of the Schiff base counterion protonation signal. J Biol Chem. 281:15208-15214, 2006.

Vogeley L, Sineshchekov OA, Trivedi VD, Sasaki J, Spudich JL, Luecke H. Anabaena Sensory Rhodopsin: A Photochromic Color Sensor at 2.0 Å. Science 30:1390-1393, 2004.

Sineshchekov OA, Jung K-H, Spudich JL Two rhodopsins mediate phototaxis to low and high intensity light in Chlamydomonas reinhardtii. Proc Natl Acad Sci USA. 99:8689-8694, 2002.

Béjà*, O., Spudich*, E.N., Spudich, J.L., Leclerc, M., DeLong, E.F. Proteorhodopsin phototrophy in the ocean. Nature 411:786-789, 2001 {*1st two authors equal contributors}.

Luecke, H., Schobert, B., Lanyi, J.K., Spudich, E.N., Spudich, J.L. Crystal structure of sensory rhodopsin II at 2.4 Å: Insights into color tuning and transducer interaction. Science. 293:1499-1503, 2001.

Search PubMed for a complete list of Dr. Spudich's publications.