My major interest is in the regulation of plant growth and cell expansion. In particular, my laboratory is focused on to environmental problems, soil salinity and elevated carbon dioxide, and how these conditions affect growth.

There is a very strong linkage between cell elongation, plant productivity and crop yields. The production of all plant parts is dependent upon the supply of external resources, such as water, mineral nutrients or carbon. Cell elongation is important for the capture of these resources, particularly when they are limiting growth. An increase in cell size will increase cell surface area, enabling roots to explore more of the soil for water and minerals, and leaves to capture more photosynthetic radiation. The size of a stressed plant is dependent upon cell production and cell expansion, both of which may be affected by stress. The intensive use of resources by man has had it side-effects. Two notable effects are the increase in atmospheric CO2 leading to the “greenhouse effect” and the increase of salinized soils of irrigated lands leading to reductions in crop productivity on those soils. In general, plants have not yet adapted to fully utilize the resources in these new environments. Through the use of new techniques in biotechnology, we can make better plants, which are more suitably adapted to these environmental conditions.

Recently, my lab has been investigating the effects of elevated atmospheric CO2 on cell wall composition and biosynthesis. We believe we can alter cell wall biosynthesis and growth in transgenic plants to enable them to better utilize the more abundant carbon source.

By inserting extra copies of the gene for UDP-Glc dehydrogenase, we have increased the activity of this key enzyme involved in the biosynthesis of plant cell walls and we have evidence that we are able to increase plant growth as a result. Such plants are likely to be more productive thereby increasing crop yields. We would expect that these plants would perform even better in an elevated CO2 environment. This hypothesis is addressed in our current investigations.

For the last two decades, my research has focused on salinity stress. The inhibition of plant growth by salinity involves two components. Initially, the plant experiences a water stress, but with time salts accumulate in the plant creating an additional ionic stress. In my laboratory, we are currently focusing on how salinity inhibits plant growth by these two components. The water stress component has been investigated by studying the immediate effects of salinity on the growth parameters regulating leaf elongation. We found that salinity increases the apparent yield threshold of the cell walls in the growing region of the leaf, which results in lower growth rates. We have interesting correlations of the plant response to the plant growth regulator, abscisic acid with salinity stress, particularly the effects on growth, cell wall yield threshold and cytosolic calcium. We are now actively investigating the effects of salinity on secretion of proteins, poly- and oligosaccharides to the cell wall.

We are investigating the ionic stress component by developing methods for quantifying cytosolic calcium and sodium activities. We are interested in the mechanisms by which the salts are absorbed into or excluded from the plant. We are investigating the regulation of sodium and calcium activities using state of the art fluorescent techniques combined with confocal microscopy in living tissues. Finally, the identification and characterization of the mechanisms regulating plant growth under saline conditions is leading to the molecular characterization and manipulation of proteins associated with salt-tolerance in plants and the stimulation of growth by elevated carbon dioxide. Currently we are investigating the effects of these environmental conditions on the expression and regulation of key proteins involved in cell wall synthesis and secretion.

I am currently teaching two courses: Plant Biology, which is taught at the junior level and Plant Physiology, which is taught at the senior and graduate level.

The Plant Biology course is an introductory course to plants designed to encourage and excite the students about plants. Students are involved in plant collections, plant identification, and a plant growing contest (winner gets dinner for two at their favorite restaurant). The course focuses on timely topics such as environmental issues, medicinal uses of plants, agriculture and biotechnology. These issues are challenged in a debate format throughout the course. There are three teams; one team that is pro issue, one that is con, and one that is judge of the debate. Teams roles are assigned by the instructor and change with each new debate, giving all a chance at each role. The debates help students develop critical thinking skills.

The Plant Physiology course is rigorous. It can be divided into four portions. The first portion of the course focuses on the quantitative aspects of transport (water, ions and sucrose) into the cell and through the plant. The second portion focuses on photosynthesis and respiration, the third portion focuses on growth, hormones and plant development, and the fourth portion attempts to integrate the first three with lectures on plant responses to various environmental stresses. Throughout this course we read scientific papers on topics already discussed in class. This is a group project. Groups work on the paper outside of class with each member having a different role. One student presents the group summary in class. Reading and discussion of scientific papers help students develop critical thinking skills.

I enjoy teaching and like to take creative and innovative approaches (some don’t work and have to be abandoned or modified). I incorporate the use of field trips, film, computers and web pages on the internet into my lectures and exercises. I also participate with the Plant-Ed bulletin board on the internet, which is a great source of information and ideas from excellent colleagues from around the world who are interested in teaching Plant Biology.

• Munns, R. J.B. Passioura, J. Guo, O. Chazen and G.R. Cramer. 2000. Cell turgor and leaf expansion: importance of timescale. Journal of Experimental Botany 51: 1495-1504
• Munns, R. J. Guo, J.B. Passioura, and G.R. Cramer. 2000. Leaf water status contols day-time but not daily rates of leaf expansion in salt-treated barley. Aust J Plant Physiol 27:949-957
• Cramer, G.R. 2002. Calcium-sodium interactions under salinity stress. In: Salinity. Environment-Plants-Molecules. Eds. A. Läuchli and U. Lüttge. Kluwer Academic Publishers, Invited Review (in press)
• Cramer, G.R, C.L. Schmidt, and C. Bidhart. 2001. Analysis of cell wall hardening and cell wall enzymes of salt-stressed maize (Zea mays) leaves. Aust J Plant Physiol 28:101-109
• Gibeaut, D.M., G.R. Cramer, and J.R. Seemann. 2001. Growth, cell walls, and UDP-Glc dehydrogenase activity of Arabidopsis thaliana grown in elevated carbon dioxide. J Plant Physiol 158:569-576
• Gustin, M.S. J.A. Benesch, and G.R. Cramer. 2002. The effect of trifluoroacetic acid on plant growth and germination and soil microbial communities. Env Tox & Chem (in press) Cramer, G.R., and S. Quarrie. 2002. Abscisic acid is correlated with the leaf growth inhibition of four genotypes of maize differing in their response to salinity. Funct Plant Biol 29:111-115
• Cramer GR. Sodium-calcium interactions under salinity stress. In: “Salinity. Environment-Plants-Molecules”. Eds. A. Läuchli and U. Lüttge. Kluwer Academic Publishers, Dordrecht, pp. 205-227 (2002).
• Tattersall EAR, Ergul A., Al-Kayal F and Cramer GR. A comparison of methods for isolating RNA from leaves of grapevine (Vitis vinifera). Am. J. Enol. Viticulture (submitted) (2004).
• da Silva FG, Iandolino A, Lim H, Baek J-M, Leslie A, Xu J, Cook DR, Bohlmann M, Al-Kayal F, Figueroa R, Cushman MA, Kabuloglu EK, Tattersall EAR, Ergul A, Cramer GR and Cushman JC. Characterizing the grape transcriptome: analysis of ESTs from multiple Vitis species. Plant Physiol. (submitted) (2004).
• Cramer GR, Cushman JC, Schooley DA, Quilici D, Vincent D, Bohlman C, Ergul A, Tattersall EA, Tillett R, Evans J, Delacruz R, Schlauch K, Mendes P. Progress in bioinformatics – the challenge of integrating transcriptomic, proteomic and metabolomic information. Acta Hort. (submitted) (2004).
• G.R. Cramer, J.C. Cushman, D.A. Schooley, D. Quilici, D. Vincent, M.C. Bohlman, A. Ergul, E.A.R. Tattersall, R. Tillett, J. Evans, R. Delacruz, K. Schlauch, P. Mendes. 2005. Progress in bioinformatics – the challenge of integrating transcriptomic, proteomic and metabolomic information. Acta Hort 689: 417-425
• F.G. da Silva, A. Iandolino, H. Lim, J.-M. Baek, A. Leslie, J. Xu, D.R. Cook, M. Bohlmann, F. Al-Kayal, R. Figueroa, M.A. Cushman, E.K. Kabuloglu, E.A.R. Tattersall, A. Ergul, G.R. Cramer, J.C. Cushman. 2005. Characterizing the grape transcriptome: analysis of ESTs from multiple Vitis species. Plant Physiol 139:574-597.
• J. Evans, E.A.R. Tattersall, W. Johnson and G.R. Cramer. 2005. Towards wine grape (Vitis vinifera) vineyard establishment in Northern Nevada: varietal studies in the dry desert climate. NAES publication #51055382. University of Nevada, Reno.
• E.A.R. Tattersall, A. Ergul, F. Al-Kayal, L. DeLuc, J.C. Cushman, and G.R. Cramer. 2005. A comparison of methods for isolating RNA from leaves of grapevine (Vitis vinifera). Am J Enol Vitic 56:400-406
• Cramer, G.R., A. Ergul, D. Vincent, M.C. Bohlmann, J. Grimplet, E.A.R. Tattersall, R.L. Tillet, J. Evans, D. Quilici, D.A. Schooley, J.C. Cushman, K.A. Schlauch , and P. Mendes. 2005. Integrative functional genomics of abiotically-stressed grapevine: a system for discovery of gene and plant functions. Proceedings of the International Grape Genomics Symposium, St. Louis, Missouri, July 12-14, 2005, Eds.,
• W. Qiu and L.G. Kovacs. pp 30 -37. Vincent, D., M. Wheatley and G.R. Cramer. 2006. Optimization of protein extraction for mature grape berry clusters. Electrophoresis 27:1853-1865
• D.C. Bowman, D. Devitt, and G.R. Cramer. 2006. Effect of salinity and N status on N uptake by tall fescue turf. J. Plant Nutr. 29:1481-1490
• D.C. Bowman, D. Devitt, and G.R. Cramer. 2006. Effect of N status on salinity tolerance of tall fescue turf. J. Plant Nutr. 29:1491-1497
• Espinoza C, A. Vega, C. Medina, K.A. Schlauch, G.R. Cramer, and P. Arce-Johnson. 2007. Analysis of gene expression associated with compatible viral diseases in grapevine cultivars. Functional and Integrative Genomics 7:95-110 DOI: 10.1007/s10142-006-0031-6
• Cramer, G.R., A. Ergül, J. Grimplet, R.L. Tillett, E.A.R. Tattersall, M.C. Bohlman, D. Vincent, J. Sonderegger, J. Evans, C. Osborne, D. Quilici, K.A. Schlauch, D.A. Schooley and J.C. Cushman. 2007. Water and salinity stress in grapevines: early and late changes in transcript and metabolite profiles. Functional and Integrative Genomics 7:111-134 (DOI: 10.1007/s10142-006-0039-y)
• Vincent, D., Ali Ergül, Marlene C. Bohlman, Elizabeth A. R. Tattersall, Richard L. Tillett, Matthew D. Wheatley, Rebekah Woolsey, David R. Quilici, Johann Joets, Karen Schlauch, David A. Schooley, John C. Cushman and Grant R. Cramer. 2007. Proteomic analysis reveals differences between Vitis vinifera L. cv. Chardonnay and cv. Cabernet Sauvignon and their responses to water deficit and salinity. Journal of Experimental Botany 58: 1873-1892 DOI:10.1093/jxb/erm012
• Grimplet, J., L.G. Deluc, M. Wheatley, K.A. Schlauch, G.R. Cramer and J.C. Cushman. 2007. Tissue-specific mRNA expression profile in grape berry tissues. In: Macromolecules and Secondary Metabolites of Grapevine and Wine. Eds.
• P. Jeandet, C. Clément and A. Conreaux. Lavoisier, Paris, France, pp. 53-59. Cramer, G.R., J. Evans, R. Ardelean, M. Keady, D. Quilici, D.A. Schooley. 2007. Impacts of regulated-deficit irrigation on the flavor components of grapes and wines. In: Macromolecules and Secondary Metabolites of Grapevine and Wine. Eds. P. Jeandet, C. Clément and A. Conreaux. Lavoisier, Paris, France, pp. 47-51.
• E.A.R. Tattersall, J. Grimplet, L. DeLuc, M.D. Wheatley, D. Vincent, C. Osborne, A. Ergül, E. Lomen, R.R. Blank, K.A. Schlauch, J.C. Cushman, G.R. Cramer. 2007. Transcript abundance profiles reveal larger and more complex responses of grapevine to chilling as compared to osmotic and salinity stress. Functional and Integrative Genomics 7:317-333 doi:10.1007/s10142-007-0051-x
• Grimplet, J., L.G. Deluc, R.L. Tillett, M.D. Wheatley, K.A. Schlauch, G.R. Cramer and J.C. Cushman. 2007. Tissue-specific mRNA expression profiling in grape berry tissues. BMC Genomics 8:187 doi:10.1186/1471-2164-8-187
• Grimplet, J., L.G. Deluc, G.R. Cramer and J.C. Cushman. 2007. Integrating functional genomics with abiotic stress responses in wine grape - Vitis vinifera. In: Advances in Molecular Breeding towards Salinity and Drought Tolerance, Eds. Eds: Matthew A. Jenks, Paul M. Hasegawa, and S. Mohan Jain. Springer, Dordrecht, The Netherlands. pp. 643-668.