Professor of Plant Biology
249 Morrill Halll MC-116
B.S., Biology, Lehigh University
Ph.D., 1979, Rutgers University
Postdoc, University of Maryland
IB 420, Plant Physiology
IB 472, Plant Molecular Biology
The broad objective of my laboratory is to understand how higher plants transduce second messenger Ca2+ signals to produce the appropriate physiological response to a specific stimulus. Current efforts are focused on understanding the organization, and patterns and regulation of expression of genes encoding calmodulin in Arabidopsis thaliana. By cDNA and genomic cloning, we have shown that a family of seven genes encodes calmodulin in Arabidopsis. Each gene has a slightly different pattern of expression at the whole organ level. We are currently asking whether the genes are differentially expressed at the level of cell-type by using the promoters of the genes to drive the expression of GUS and GFP reporter genes, in transgenic Arabidopsis plants. We found that the seven calmodulin genes in Arabidopsis encode four isoforms of the protein, which may be unique to calmodulins in higher plants. To determine whether there are significant differences among calmodulin isoforms, we are taking both biochemical and genetic approaches. In the genetic approach, we found that each of the isoforms functionally complements a yeast calmodulin null. However, T-DNA insertional knockouts in Arabidopsis have different phenotypes. In the biochemical approach, we have constructed E. coli strains engineered to overexpress cloned calmodulin cDNAs. We are comparing the abilities of these recombinant proteins to activate calmodulin-regulated enzymes in vitro, to bind Ca2+, and to bind protein and model peptide substrates.
Current funding from BARD (in collaboration with Maggie Levy, Hebrew University and A.S.N. Reddy, Colorado State University) supports work on the effects of Ca2+ signaling on IQD1 protein function. IQD1 is required for glucosinolate synthesis, which deters feeding of insect herbivores.
Current funding from NSF (in collaboration with Steve Huber) supports work on understanding the impact of Ca2+ signaling on brassinosteroid signaling.
Tang, J., Zielinski, R., Aldea, M., and DeLucia, E. (2009) Spatial Correspondence of Photosynthesis and Chemical Defense in Arabidopsis thaliana Following Herbivory by Trichoplusia ni. Physiol. Plant. 137: 115–124.
Ali R, Zielinski RE, Zangerl AR, Crofts AR, Berenbaum MA and DeLucia EH (2006) Expression of plant cyclic nucleotide gated cation channels in yeast. Journal of Experimental Botany 57: 125-138.
Tang JY, Zielinski RE, Zangerl AR, Crofts AR, Berenbaum MA and DeLucia EH (2006) The differential effects of herbivory by first and fourth instars of Trichoplusia ni (Lepidoptera: Noctuidae) on photosynthesis in Arabidopsis thaliana. Journal of Experimental Botany 57: 527-536.
Hua, B.-G., Mercier, R. W., Zielinski, R. E., and Berkowitz, G. A. (2003). Functional interaction of calmodulin with a plant cyclic nucleotide gated cation channel. Plant Physiol. Bioche m. 41, 945-954
Nelissen, H., Clarke, J. H., DeBlock, M., DeBlock, S., Vanderhaeghen, R., Zielinski, R. E., Dyer, T., Lust, S., Inze, D., and Van Lijsebettens, M. (2003) DRL1, a homologue of the yeast KTI12/TOT4 protein, has a function in meristem activity and organ growth in plants. Plant Cell 15, 639-654.