Personal Information

I.Home Adress

Mikve-Israel, Doar Holon

II. Education

Tel Aviv University, The Weizmann Institute of Science, Max-Planck Institute, Cologne, Germany.

III. Research Grants

EC, Israeli Ministry of science, Italy-Israel collaboration

Research Interests

1. Signal transduction pathways induced by different stresses in plants
2. Generating plants with improved tolerance to biotic and abiotic stresses.
3 Transcription factors mediating amino acid biosynthesis.
4. Correlations between proline cycle, proline-rich-proteins and stress.
5. The Bt delta endotoxin Cry1C in insect resistant plants and its interaction with specific membrane lipid rafts and receptors.

Courses

Publications

A. Regev, M. Keller, N. Strizhov, B. Sneh, E. Prudovsky, I. Chet, E. Ginzberg, Zs. Koncz-Kalman, C. Koncz, J. Schell, and A. Zilberstein (1996) Synergistic larvicidal activity of delta-endotoxin and bacterial endochitinase against Spodoptera littoralis larvae. Appl. Environ. Microbiol. 62: 3581-3586.

N. Strizhov, M. Keller, Z. Koncz-Kalman, A. Regev, B. Sneh, J. Schell, C. Koncz and A. Zilberstein (1996) Mapping of the entomocidal fragment of Spodoptera-specific Bacillus thuringiensis toxin CryIC. Mol. Gen. Genet. 253: 11-19.

N. Strizhov, M. Keller, J. Mathur, Z. Koncz-Kalman, D. Bosch, E. Prudovsky, J. Schell, B. Sneh, C. Koncz and A. Zilberstein (1996) A synthetic cryIC gene encoding a Bacillus thuringiensis delta-endotoxin, confers Spodoptera resistance in alfalfa and tobacco. Proc. Natl. Acad. Sci. USA. 93: 15012-15017.

N. Strizhov, E. Abraham, L. Okresz, S. Blickling, A. Zilberstein, J. Schell, C. Koncz and L. Szabados (1997) Differential expression of two P5CS genes controlling proline accumulation during salt-stress is regulated by ABA1, ABI1, and AXR2 in Arabidopsis. Plant J. 12: 557-569.

H. Eilenberg, U. Hanania and A. Zilberstein (1998) Characterization of rbcS genes in the fern Pteris vittata and their regulation by red and blue light. Planta 206: 204-214.

I. Ginzberg, H. Stein, Y. Kapulnik, L. Szabados, N. Strizhov, J. Schell, C. Koncz and A. Zilberstein (1998) Characterization of two different cDNAs of delta1-pyrroline-5-carboxylate synthase in alfalfa and their rapid increase in transcription as a response to salt-stress. Plant Mol. Biol. 38: 755-764.

S. Pnini-Cohen, A. Zilberstein, S. Schuster, A. Sharon and Z. Eyal (2000) Elucidation of Septoria tritici x wheat interactions using GUS expressing isolates. Phytopathology 90: 297-304.

J. Gressel and A. Zilberstein (2003) Let them eat (GM) straw. Trends in Biotech. 21: 525-530.

E. Zuther, S. Huang, J. Jelenska, H. Eilenberg, A.M. Arnold, X. Su, A. Sirikhachornkit, J. Podkowinski, A. Zilberstein, R. Haselkorn and P. Gornicki (2004) Complex nested promoters control tissue-specific expression of acethyl-CoA carboxylase genes in wheat. Proc. Natl. Acad. Sci. USA 101: 1403-1408.

D. Avisar, M. Keller, E. Gazit, E. Prudovsky, B. Sneh, and A. Zilberstein (2004) The role of Bacillus thuringiensis Cry1C and Cry1E separate structural domains in the interaction with Spodoptera littoralis gut epithelial cells. J. Biol. Chem. 279: 15779-15786.

D. Avisar, M. Segal, B. Sneh and A. Zilberstein (2005) Cell cycle dependent resistance to Bacillus thuringiensis Cry1C toxin in Sf9 cells . J. Cell Science 118: 3163-71.

G. Miller, H. Stein, A. Honig, Y. Kapulnik and A. Zilberstein (2005) Responsive modes of Medicago sativa proline dehydrogenase genes during salt stress and recovery dictate free proline accumulation. Planta 222: 70-79.

H. Eilenberg, S. Pnini-Cohen, S. Schuster, A. Movtchan, H. Shoshan and A.Zilberstein (2006) Isolation and characterization of chitinases from pitchers of the carnivorous plant Nepenthes khasiana. J. Exp. Bot. 57: 2775-2784.

H. Eilenberg and A. Zilberstein (2007) Carnivorous Pitcher Plants Towards Understanding the Molecular Basis of Prey Digestion. In: Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Teixeira da Silva JA (Ed) Global Science Books, London, UK (In Press).

CV

A. EDUCATION
1979 Ph.D - Plant molecular biology Tel Aviv University.
1980-1983 Postdoc Fellow Yeast and bacterial molecular genetics
The Weizmann Inst. of Science.

B. FURTHER STUDIES
1985 to 1994 (summers) Max-Planck Institute, Cologne Visiting Scientist
1991 (summer) University of Chicago, Chicago Visiting Scientist
1999 (sabbatical) Max-Planck Institute, Cologne Visiting Scientist
2001-2002 (summers) Max-Planck Institute, Cologne Visiting Scientist
2002 (summer) Max-Planck Institute, Cologne Visiting Scientist
2005 (sabbatical) Max-Planck Institute, Cologne Visiting Scientist

C. ACADEMIC AND PROFESSIONAL EXPERIENCE
1974-1979 Tel-Aviv University, Dept. of Botany Assistant
1980-1983 The Weizmann Inst., Biochemistry Dept. Postdoc
1984-1987 Tel-Aviv University, Dept. of Botany Lecturer
1988-1997 Tel-Aviv University, Dept. of Botany Senior Lecturer
1998-to date Tel-Aviv University, Dept of Pl. Sciences Associate Professor

Selected Publications
M. Flaishman, Z. Eyal, A. Zilberstein, C. Voisard and D. Haas (1996) Suppression of Septoria tritici blotch and leaf rust of wheat by recombinant cyanide producing strains of Pseudomonas putida BK8661. Mol. Plant-Microbe Interact. 9: 642-645.

M. Keller, B. Sneh, N. Strizhov, E. Prudovsky, A. Regev, C. Koncz, J. Schell and A. Zilberstein (1996) Digestion of delta-endotoxin by midgut proteases may explain reduced sensitivity of advanced instar larvae of Spodoptera littoralis to CryIC. Insect Biochem. Mol. Biol. 26: 365-373.

T. Halperin, S. Shuster, S. Pnini-Cohen, A. Zilberstein and Z. Eyal (1996) The suppression of pycnidial production on wheat seedlings following sequential inoculations by isolates of Septoria tritici. Phytopathology 86: 728-732.

A. Regev, M. Keller, N. Strizhov, B. Sneh, E. Prudovsky, I. Chet, E. Ginzberg, Zs. Koncz-Kalman, C. Koncz, J. Schell, and A. Zilberstein (1996) Synergistic larvicidal activity of delta-endotoxin and bacterial endochitinase against Spodoptera littoralis larvae. Appl. Environ. Microbiol. 62: 3581-3586.

N. Strizhov, M. Keller, Z. Koncz-Kalman, A. Regev, B. Sneh, J. Schell, C. Koncz and A. Zilberstein (1996) Mapping of the entomocidal fragment of Spodoptera-specific Bacillus thuringiensis toxin CryIC. Mol. Gen. Genet. 253: 11-19.

N. Strizhov, M. Keller, J. Mathur, Z. Koncz-Kalman, D. Bosch, E. Prudovsky, J. Schell, B. Sneh, C. Koncz and A. Zilberstein (1996) A synthetic cryIC gene encoding a Bacillus thuringiensis delta-endotoxin, confers Spodoptera resistance in alfalfa and tobacco. Proc. Natl. Acad. Sci. USA. 93: 15012-15017.

N. Strizhov, E. Abraham, L. Okresz, S. Blickling, A. Zilberstein, J. Schell, C. Koncz and L. Szabados (1997) Differential expression of two P5CS genes controlling proline accumulation during salt-stress is regulated by ABA1, ABI1, and AXR2 in Arabidopsis. Plant J. 12: 557-569.

S. Pnini-Cohen, S. Ezrati, A. Zilberstein, S. Schuster and Z. Eyal (1997) The suppression of pycnidial production on wheat seedlings following inoculation with mixtures of Septoria tritici isolates. Proc. of The Mediterranean Phytopathological Union, pp. 597-601.

H. Eilenberg, U. Hanania and A. Zilberstein (1998) Characterization of rbcS genes in the fern Pteris vittata and their regulation by red and blue light. Planta 206: 204-214.

I. Ginzberg, H. Stein, Y. Kapulnik, L. Szabados, N. Strizhov, J. Schell, C. Koncz and A. Zilberstein (1998) Characterization of two different cDNAs of delta1-pyrroline-5- carboxylate synthase in alfalfa and their rapid increase in transcription as a response to salt-stress. Plant Mol. Biol. 38: 755-764.

S. Pnini-Cohen, A. Zilberstein, S. Schuster, A. Sharon and Z. Eyal (2000) Elucidation of Septoria tritici x wheat interactions using GUS expressing isolates. Phytopathology 90: 297-304.

J. Gressel and A. Zilberstein (2003) Let them eat (GM) straw. Trends in Biotech. 21: 525-530.

E. Zuther, S. Huang, J. Jelenska, H. Eilenberg, A.M. Arnold, X. Su, A. Sirikhachornkit, J. Podkowinski, A. Zilberstein, R. Haselkorn and P. Gornicki (2004) Complex nested promoters control tissue-specific expression of acethyl-CoA carboxylase genes in wheat. Proc. Natl. Acad. Sci. USA 101: 1403-1408.

D. Avisar, M. Keller, E. Gazit, E. Prudovsky, B. Sneh, and A. Zilberstein (2004) The role of Bacillus thuringiensis Cry1C and Cry1E separate structural domains in the interaction with Spodoptera littoralis gut epithelial cells. J. Biol. Chem. 279: 15779-15786.

D. Avisar, M. Segal, B. Sneh and A. Zilberstein (2005) Cell cycle dependent resistance to Bacillus thuringiensis Cry1C toxin in Sf9 cells . J. Cell Science 118: 3163-71.

.G. Miller, H. Stein, A. Honing, Y. Kapulnik and A. Zilberstein (2005) Responsive modes of Medicago sativa proline dehydrogenase genes during salt stress and recovery dictate free proline accumulation. Planta 222: 70-79.

H. Eilenberg, S. Pnini-Cohen, S. Schuster, A. Movtchan, H. Shoshan and A.Zilberstein (2006) Isolation and characterization of chitinases from pitchers of the carnivorous plant Nepenthes khasiana. J. Exp. Bot. 57: 2775-2784.

H. Eilenberg and A. Zilberstein (2007) Carnivorous Pitcher Plants Towards Understanding the Molecular Basis of Prey Digestion. In: Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues. Teixeira da Silva JA (Ed) Global Science Books, London, UK (In Press)

Patents
N. Strizhov, J. Schell, A. Zilberstein, M. Keller, B. Sneh and C. Koncz. (2000). Synthetic Bacillus thuringiensis Cry1C gene encoding insect toxin. USA Patent No.3
6043415, March 28, 2000. (Ramot of Tel Aviv University, Israel and Max-Planck Institute, Koln, Germany).

H. Stein, A. Zilberstein, G. Miller and Y. Kapulnik (2000). Plants tolerant of environmental stress conditions. PCT-USA09/490,454, 2000. (Ramot of Tel Aviv University, Israel).

A. Zilberstein, H. Eilenberg, S. Schuster (2001) Chitinases derived from carnivorous plants. PCT-USA 60/261834 (Ramot of Tel Aviv University, Israel).

H. Stein, A. Zilberstein, G. Miller (2003) Method of identifying organisms having a mutated signal transduction pathway. PCT-USA 60/437,985 (Ramot of Tel Aviv University, Israel).

Degrees Supervised
21 MSc graduates, 9 Ph.D. graduates, presently with 2 Ph.D. students, 4 M.Sc. students, 1
Post Doc .

Currently supervised students:

Research students...

Aviah Zilberstein's group

Plant Biotechnology: Combating environmental stresses and improvement of nutritional sources.

A) Sensing and overcoming stress effects in plants
Global effects of desertification and soil stalinization are predicted to cause dramatic changes in arable lands in the 21st century. Stress tolerant vegetation is one of the main solutions that might reduce these negative processes and contribute to the maintenance of healthy environment, enriched in various organisms including plants and animals.
We are studying plant responses to environmental stresses such as drought, salinity, low temperatures and pathogenic attacks. Stress sensing starts by activating various endogenous signaling pathways leading to the appearance of stress related new proteins and to changes in metabolic pathways. Many plants respond to various stresses by increasing the level of free proline that acts as an osmotic compensator when plant cells suffer from water loss. We are currently studying regulatory pathways that sense the stress and initiate the cellular responses responsible for the production of stress protective molecules including proline and sugars.
Recently we have developed a novel forward genetics strategy to identify T-DNA knockout mutants defective in components involved in plant responses to abiotic stresses. It is based on the stress-induced-mode of the plant proline cycle that leads to high proline accumulation. T-DNA tagged mutants that are defective in normal regulation of the proline cycle are identified and genes corresponding to those inactivated by T-DNA insertions are being studied. Many mutants have already been identified and their characterization will form a collection of new gene candidates for studying stress signaling cascades and improving osmotic stress tolerance in plants.

B) The role of the cell-wall-linker protein (CWLP) in the formation of cell wall-plasma membrane-cytosol continuum
The CWLP is proline rich protein with three trans-membrane domains, suggested to function as a linker between the cell wall and the cytosol. By using CWLP-GFP it was possible to localize the CWLP to the cell membrane and show that its overexpression renders plants more tolerant to water shortage, prevents cellular plasmolysis and keeps the intact structure of the cytoskeleton. We are currently characterizing the role of the CWLP different domains and their involvement in the interaction with cytoskeletal, cell membrane and cell wall components.

C) Molecular basis of Tamarix salt tolerance.
Tamarix species (salt cedar) are relatively tolerant to salinity. We have compared the response to increasing NaCl concentrations of Tamarix tetragyna and Tamarix aphylla. Presently differences in metabolic profiles as well as differential sensitivity of chloroplast ATP synthase and mitochondrial glycine dehydrogenase have been identified. However, despite the effect of high salt concentrations on important energy providing systems in the chloroplast and mitochondria, the two species are able to produce high biomass levels when grown under extremely saline conditions. Other molecular parameters of stress response are currently being studied.

D) Plants as essential nutritional sources.
Given that the increase in world population in this century (above 10 billions) will not be accompanied by anequivalent increase in food sources, there is an essential need to enrich our existing food sources with higher levels of components that are not synthesized by human cells. Plants are the most prominent sources for these nutritional components.
We explore the involvement of regulatory proteins, such as transcription factors, in controlling the synthesis of essential amino acids. We have identified a family of bZIP transcription factors capable of controlling the genes encoding key enzymes of the aspartate pathway. Further involvement of these transcription factors in regulatiing biosynthetic pathways during dark and sugar depletion conditions is being studied.

E) Rendering plant resistant to insects: Characterization of membrane receptors of the Bt toxin Cry1C in insect cells.
The Bacillus thuringiensis toxin Cry1C has been successfully used as a bacterial-produced bioinsecticide. We modified the cry1C codon usage and showed that its efficient expression in transgenic plants rendered them tolerant to specific Lepidopteran pests. However, its usage as a primary or alternative Bt toxin in bacterial sprays and in commercially grown transgenic plants depends on the characterization of Cry1C intoxication process.
Our earlier study showed that all the three structural domains of Cry1C interact specifically with the cell membrane of sensitive insect cells, suggesting a multi-step interaction. This interaction depends on the presence of lipid rafts in the cell membrane and therefore does not occur during G2/M phase of the cell cycle. Membrane proteins involved in this interaction are currently being isolated and characterized using cross-linking and immuno-precipitation approaches.