Address:

Biology Department

E. 502 Boone Ave.

Spokane, WA 99258-0006

Courses Taught:

Cell Biology, Genetics & Evolution, General Microbiology, Virology, Introduction to Biological Diversity (Gonzaga-in-Chimfunshi, Zambia) http://www.gonzagainchimfunshi.com

Education:

B.S., Biology, Lewis and Clark College, Portland, OR (1981)

Ph.D., Plant Physiology, Washington State University, Pullman, WA (1987)

Professional Experience:

1987-1990: University of California at Davis, Botany Department, Postdoctoral Research Associate, in the laboratory of Dr. John Harada 

1992-1997: Gonzaga University Spokane, WA., Biology Department, Assistant Professor of Biology. 1990-1992: University of California at Davis, Botany Department, Postdoctoral Research Associate, in the laboratory of Dr. Steven Theg 

1997-present; Gonzaga University Spokane, WA., Biology Department, Associate Professor of Biology. Fall 2000: Visiting Scientist, Institute of Biological Chemistry, Washington State University, in the laboratory of Dr. David Kramer 

Research Interests:

For a long time I have been fascinated by how the compartments inside cells take on their specific shape and structure. The highly compartmentalized plant cell is a marvel of evolution. Each compartment inside the cell plays a specific role in the life of the cell, and helps to determine the structure and function of the cell as a whole. Studies of the proteins in each compartment tell us a great deal about what that compartment's function is. Understanding how specific proteins get to different compartments inside of the cell was the focus of my postoctoral studies. My recent focus has been on how the ion calcium moves inside of the plant cell.

Recently my students and I have found a strong calcium pump located in the plant chloroplast thylakoid membrane. This pump functions in the light to concentrate calcium ions inside the thylakoid lumen. In this location calcium is available for assembly into the oxygen-evolving complex of photosystem II. The oxygen-evolving complex is responsible for photosynthetic oxygen production by plants and is the enzyme responsible for the 20% oxygen that is in our present atmosphere. The oxygen-evolving complex has a strict requirement for calcium and will not function unless calcium is available inside the thylakoid lumen. The calcium pump discovered in my lab at Gonzaga University provides a way for large amounts of calcium to cross the thylakoid membrane and accumulate in the thylakoid lumen.

In our studies we have also noted that large amounts of calcium appear to flow into the thylakoid lumen when light strikes a plant and that the calcium appears to be released by the thylakoid lumen when the lights are turned off. This is interesting because several key enzymes involved in photosynthetic carbon dioxide fixation are strongly inhibited by calcium. It seems likely that these enzymes are regulated in part by calcium flow across the thylakoid membrane. We are now preparing to measure the concentration of free calcium inside the thylakoid lumen in the light and in the dark. Through these studies we hope to determine the magnitude of calcium flow across the thylakoid membrane during the light dark cycle. These measurements will allow us to see if there is a correlation between calcium flow across the thylakoid membrane and the regulation of carbon dioxide fixation by plants.

Selected Publications:

Johnson, C.H., Shingles R., & Ettinger, W.F. (2006) Regulation and Role of Ca⁺⁺ Fluxes in the Chloroplast., Chapter 20 in "The Structure and Function of Plastids" Robert R. Wise & J. Kenneth Hoober eds. Advances in Photosynthesis and Respiration Series, Springer, The Netherlands. 403-416

Hou, H.J.M., Zhang, X., Liu, H. *Stevens, J., *Young, E., *Lien, T., *Dempsey, E.*, Ettinger, W.F. & Gunner, M. (2005)  "Photodamage of one bacteriopheophytin molecule in the photosynthetic reaction center from R. sphaeroides", in Photosynthesis: Fundamental Aspects to Global Perspectives, A. Van Der Est and D. Bruce eds., Vol 1, pp. 501-503

Avenson, T. J., Kanazawa, A., Cruz, J. A., Takizawa, K., Ettinger, W. F., and Kramer, D. M. (2005). "Integrating the proton circuit into photosynthesis: progress and challenges." Plant Cell and Environment 28: 97-109.

Li, T., Sirakova, D., Rogers, L., Ettinger, W.F., & Kolattukudy, P.E. (2002) Regulation of Constitutively Expressed and Induced Cutinase Genes by Different Zinc Finger Transcription Factors in Fusarium solani f. sp. pisi (Nectria haematococca) J. Biol. Chem.  277: 7905-7912.

Ettinger, W.F., *Clear, A.M., *Fanning, K.J., *Peck, M.-L. (1999) Identification of a Ca⁺⁺/H⁺ antiporter in the plant chloroplast thylakoid membrane. Plant Physiol. 119: 1379-1385.