tsharkey@msu.edu
Professor, Department Chair
  • Ph.D., 1980 Michigan State University
  • B.S. 1974, Michigan State University
  • Postdoctoral Fellow, 1980-1982, Australian National University
  • Assist./Assoc. Research Professor, 1982-1987, Desert Research Institute, Reno, NV
  • Assist. Professor, 1987-1988, Assoc. Professor, 1988-1991, Professor, 1991-2008, University of Wisconsin, Madison
  • Highly Cited Researcher, Institute for Scientific Information

tsharkey@msu.edu
410 Biochemistry Building
Michigan State University
East Lansing, MI 48824-1319 Office: 517-353-3257
Lab: 517-353-3257




Publication search:

Thomas D. Sharkey

Research Interests

Research in the Sharkey lab focuses on three main areas centered on the biochemistry and biophysics of gas exchange reactions between plants and the atmosphere. Photosynthetic carbon fixation from carbon dioxide uptake through to synthesis of sucrose and starch is one major area of research. Recent progress includes demonstration that starch breakdown in leaves results in the formation of b-maltose and this is the predominant form of carbon exported from chloroplasts at night.

A second major research focus area is biochemical analysis of isoprene emission from plants. Isoprene is made by the methyl erythritol 4-phosphate (MEP) pathway that is unique to bacteria and plastids of plants. Plants make isoprene to help them cope with rapid increases in temperature that can occur in sunlight (see the figure). The effects of temperature and development on the expression of all of the genes in the MEP pathway, plus isoprene synthase, have been examined. Several of the genes exhibit circadian regulation, although the protein amounts for these enzymes do not vary over the course of a day.

Since isoprene emission appears related to heat tolerance, we initiated a third focus area, studies of heat tolerance mechanisms of photosynthesis. We have found that the energy gradient for making ATP dissipates faster after turning off the light when leaves are at high temperature. This could indicate that heat causes thylakoid membranes to become leaky. We hope to determine if isoprene can counteract this leakiness.

Recent Publications

Wiberley AE, Donohue AR, Meier ME, Westphal MM, Sharkey TD. Regulation of isoprene emission in Populus trichocarpa leaves subjected to changing growth temperature. Plant Cell Environ. 2008 Feb;31(2):258-67. Link to PubMed

Seetang-Nun,Y, Sharkey,TD and Suvachittanont,W. (2007) Molecular cloning and characterization of two cDNAs encoding 1-deoxy-D-xylulose 5-phosphate reductoisomerase from Hevea brasiliensis. Journal of Plant Physiology doi:10.1016/j.physletb.2003.10.071. Link to PubMed

Calfapietra,C, Wiberley,AE, Falbel,TG, Linskey,AR, Mugnozza,GS, Karnosky,DF, Loreto,F and Sharkey,TD. (2007) Isoprene synthase expression and protein levels are reduced under elevated O3 but not under elevated CO2 (FACE) in field-grown aspen trees. Plant, Cell & Environment 30: 654-661. Link to PubMed

Schrader,SM, Kleinbeck,KR and Sharkey,TD. (2007) Rapid heating of intact leaves reveals initial effects of stromal oxidation on photosynthesis. Plant, Cell & Environment 30: 671-678. Link to PubMed

Sharkey,TD, Bernacchi,CJ, Farquhar,GD and Singsaas,EL. (2007) Fitting photosynthetic carbon dioxide response curves for C3 leaves. Plant, Cell & Environment 30: 1035-1040. Link to PubMed

Lu,Y, Steichen,JM, Yao,J and Sharkey,TD. (2006) The role of cytosolic a-glucan phosphorylase in maltose metabolism and the comparison of amylomaltase in Arabidopsis and E. coli. Plant Physiology 142: 878-889. Link to PubMed

Weise,SE, Schrader,SM, Kleinbeck,KR and Sharkey,TD. (2006) Carbon balance and circadian regulation of hydrolytic and phosphorolytic breakdown of transitory starch. Plant Physiology 141: 879-886. Link to PubMed

Lu,Y, Steichen,JM, Weise,SE and Sharkey,TD. (2006) Cellular and organ level localization of maltose in maltose-excess Arabidopsis mutants. Planta 218: 466-473. Link to PubMed

Sharkey, T. D., Yeh, S., Wiberley, A. E., Falbel, T. G., Gong, D. and Fernandez, D. E. (2005) Evolution of the isoprene biosynthetic pathway in kudzu. Plant Physiology 137: 700-712.Link to PubMed

Wolfertz, M., Sharkey, T. D., Boland, W. and Kühnemann, F. (2004) Rapid regulation of the methylerythritol 4-phosphate pathway during isoprene synthesis. Plant Physiology 135: 1939-1945. Link to PubMed  MORE