Prof. Rafael Perl-Treves

Telephone
Email
rafi.perl@gmail.com
Office
The Suissa Life Sciences Building (212), 3rd floor, Room 306
    CV

    Education

     

    1982, BSc, with honors, Faculty of Agriculture, Field Crop Department, Hebrew University, Rehovot, Israel

     

    1985, MSc, Plant Genetics Department, Weizmann Institute of Science, Rehovot, Israel

     

    1990, PhD, Plant Genetics Department, Weizmann Institute of Science, Rehovot, Israel

     

    1990-1992, Postdoctoral research, Cornell University, Ithaca NY, USA

     

    Positions

     

    2007-present, Associate Professor

    Plant Molecular Genetics and Development

    The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University,

    Ramat-Gan, Israel

     

    1999-2007, Senior Lecturer

    Plant Molecular Genetics and Development

    The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University,

    Ramat-Gan, Israel

     

    2002, Sabbatical Fellow

    Plant/pathogen interaction

    Plant Industry Division, CSIRO, Wembley (Perth) West Australia

     

    1993-1999, Lecturer

    Plant Molecular Genetics and Development

    Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel

     

     

    Public Scientific Activities

     

    2005-2009, Treasurer of the Israeli Society of Plant Sciences

     

    2008, Scientific Board of the Cucurbitaceae 2008 International Conference

    Avignon, France

     

    2006-2007, Head of the Israeli Society of Plant Sciences

     

    2005-2007, Evaluation Committee for Field and Garden Crops, BARD

     

    2001-2005, Evaluation and Steering Committee for Agriculture according to Halachic Law, Chief Scientist’s Office of the Israeli Ministry of Agriculture

     

    1999-2000, Scientific Board organizing the Cucurbitaceae 2000 International Conference, Ma’ale Ha’Hamisha, March 2000

     

    1994-1996, Evaluation Committee for Field and Garden Crops, BARD and Chief Scientist's Office of the Israeli Ministry of Agriculture

     

     

    Past and Present Members of our Group (*=presently in the lab)

     

    *Dr. Irina Kovalski, New immigrant Scientist and lab assistant, 1993-present;

    Thesis/Project: Development and mapping of RAPD markers in melons

     

    Dr. Leah Silberstein, Postdoctoral Fellow, 1993-2002

    Thesis/Project: Development and mapping of RFLP markers in melons

     

    Dr. Huang Ruguo, Postdoctoral Fellow - part time, 1995

    Thesis/Project: RAPD and RFLP genotyping of pathogenic fungi and melon varieties

     

    Dr. Xiang Yu, Postdoctoral Fellow, 1995

    Thesis/Project: Cloning of sex related genes in cucumber

     

    Dr. Naama Kessler, Laboratory assistant part-time, 1998-1999

    Thesis/Project: Cloning characterization of male specific cDNAs in cucumber

     

    Anat Kahana, Ph.D., 1998 (joint supervision with Prof. Y. Cohen)

    Thesis: Molecular characterization of sex expression in cucumber

     

    Naomi Rosenmann, M.Sc., 1996

    Thesis: Isolation and characterization of homeotic genes in cucumber

     

    Asya Stepansky,  M.Sc., 1998

    Thesis: Molecular and phenotypic variation in the melon germplasm

     

    Yariv Brotman, M.Sc., 2000

    Thesis: Cloning and linkage analysis of resistance-gene homologues from melon

     

    Anat Goldberg, M.Sc., 2002

    Thesis: Genes expressed in buds of C. sativus

     

    Talia Saraf-Levy, Ph.D., 2003

    Thesis: Role of ethylene perception in cucumber sex expression

     

    Anat Goldberg, M.Sc., 2002

    Thesis: Genes expressed in buds of C. sativus

     

    Dr. An Lizheé, Postdoctoral Fellow, 2000

    Project: Genetic transformation of C. sativus

     

    Salih Kafkas, Ph.D. student at Chukrova University, Turkey. Joint supervision with Prof. Selim Cetiner, performed a two-year project at Bar-Ilan University, 1998 – 2000

    Project: Wild Pistacia species from Turkey: sex expression, genetic diversity and evaluation as rootstock for P. vera

     

    Dr. Premanand Rajagopalan, Postdoctoral Fellow, 2001-2003

    Project: Genetic transformation of Cucumis sativus

     

    Yariv Brotman, Ph.D., 2004

    Thesis: Mapping of resistance-genes from melon

     

    Mor Grinberg, M.Sc., 2003

    (Joint supervision Dr. Victoria Sorozker and Dr. Eric Palewski, A.R.O.)

    Thesis: Interaction between cucumber and the broad mite

     

    Michal Segal, M.Sc., 2003

    Thesis: Pto kinase homologs in melon

     

    Isaac Goldenberg, M.Sc., 2004

    Thesis: Mapping resistance genes in melon

     

    Ran Herman, Ph.D., 2008

    Thesis: Inheritance & mapping of Fusarium race 1,2 resistance in melon

     

    Zvi Zvirin, M.Sc., 2006

    Thesis: Mapping Fusarium resistance in melon

     

    Anat Hendelman, M.Sc., 2006

    Thesis: Expression of microRNA in developing cucumber flowers

     

    Avital Baniel, M.Sc., 2007

    Thesis: Control of fruit set in Cucumis

     

    Valentina Davidovich, M.Sc. student, 2010

    Thesis: Engineered hormonal changes in cucumber

     

    Ohad Yogev, M.Sc., 2009

    Thesis: Melon root transformation 

     

    Mor Grinberg, Ph.D., 2009

    (Joint supervision Dr. Victoria Sorocker, A.R.O.)

    Thesis: Interaction between cucumber and the broad mite

     

    Isaac Goldenberg, Ph.D., 2009

    (Joint supervision Dr. Nurit Katzir, A.R.O.)

    Thesis: Positional cloning of resistance genes in melon

     

    Avida Shoham, M.Sc. student, 2010

    (Joint supervision Dr. Ron Cohen, A.R.O.)

    Thesis: Partial resistance of melons to Fusarium oxysporum

     

    *Toiba Safronova, M.Sc. student, 2008-

    (Joint supervision Dr. Victoria Sorocker, A.R.O.)

    Thesis: Interaction between tomato, the broad mite and whiteflies

     

    *Dikla Elul, M.Sc. student, 2009-

    (Joint supervision Dr. Victoria Sorocker, A.R.O.)

    Thesis: Interaction between tomato, the broad mite and whiteflies

     

    Rina Zagouri, M.Sc. student, 2010

    Thesis: Cloning of the sex determining gene androecious in cucumber

     

    Michael Normantovich, M.Sc. student, 2010

    Thesis: Composite melon plants expressing Fusarium resistance

     

    Golan Miller, M.Sc. student, 2011

    Thesis: Control of fruit set in Cucumis

     

    Yulia Goltsev, M.Sc. student, 2011

    Thesis: Hormonal control of fruit set in Cucumis

     

    *Anastacia Stovbun, M.Sc student, 2013

    Project: Positional cloning of resistance genes in melon

     

    Arie Amitzur , M.Sc student, 2012

    Thesis: Mapping of the parthenocarpy trait in cucumber

     

     *Michael Normantovich, Ph.D. student, 2010-

    Thesis: Fusarium and PRSV resistance genes in melon  

     

    *Golan Miller, Ph.D. student, 2012 -

    Thesis: Fusarium-melon interaction

     

    *Yulia Goltsev, Ph.D. student, 2012 -

    Thesis: Hormonal control of fruit set in Cucumis

     

    *Arie Amitzur , Ph.D. student, 2013 -

    Thesis: Potyvirus resistance genes in melon

     

     

    In addition, I have provided academic supervision to graduate students who performed their research at the Agricultural Research Organization:

     

    Esther Aftergoot, M.Sc. (co-supervisor Dr. Ilan Paran), 1997-1999

    Hila Spanov, M.Sc. (co-supervisor Dr. Yedidya Gafni), 2001-2003

    Natalia Gerchikov, M.Sc. (co-supervisor Dr. Idit Ginzburg), 2002-2005

    Tal Twito, Ph.D. (A.R.O. and Hebrew University, co-supervisors Dr. Uri Lavi and Prof. Yossef Hillel), 2002-2009

    Noga Yaakov, M.Sc. (co-supervisor Dr. Yedidya Gafni), 2003-2006

    Dvora Schwarzberg, Ph.D. (co-supervisor Dr. David Granot), 2004-2008

    Sarit Faraj-Barhom, Ph.D. (co-supervisor Dr. Amnon Lers), 2004-2009

    Efrat Saar-Glick, Ph.D. (co-supervisor Dr. Yedidya Gafni), 2004-2009

    Pinhas Kritz, M.Sc. (co-supervisor Dr. Idit Ginzburg), 2005-2007

    Yelena Ivanov, Ph.D. (co-supervisor Dr. David Kenigsbuch), 2006-

    Shahar Oheli, M.Sc. (co-supervisor Dr. Oz Barazani), 2008-2010

    Anat Krepkanovich, M.Sc. (co-supervisor Dr. Yuval Cohen), 2009-2010

    Nir Hanin, M.Sc. (co-supervisor Dr. Oz Barazani), 2013

    Amalia Aboudi, Ph.D. (co-supervisor Dr. Yedidya Gafni), 2009-

    Amir Dekel, M.Sc. (co-supervisor Dr. Victoria Sorocker), 2011-

    Research

     

     

    MOLECULAR GENETICS OF CUCURBITS

     

    Overview of Research Projects

    Our laboratory carries out molecular genetic research, mostly in plants of the Cucurbitaceae family. We have analyzed the melon and cucumber genomes using mapping approaches, and investigated the interaction of these plants with pathogens and insects. We also studied sex differentiation and fruit set in cucumbers at the molecular level. Our projects ask genetic and developmental-genetic questions on plant reproduction, and on disease resistance genes, and yield biotechnological assets in the form of diagnostic DNA markers to assist breeding, and cloned genes of biotechnological interest.

     

    Genetic mapping and genome analysis in Cucumis

    Broad scale analysis of eukaryotic genomes is one of the challenges of modern biology, starting from the construction of detailed genetic maps, and culminating in reverse-genetic approaches to isolate and study the function of economically important genes. Our lab contributed to the development and use of such discipline for crops of the cucurbit family, namely Cucumis sativus (cucumber) and Cucumis melo (melon). We have become recognized among the few laboratories that developed markers and performed genome analysis in Cucumis crops, and we collaborate with other groups and breeders, in Israel and elsewhere.

     

    Genetic diversity studies

    Seed collections of wild and primitive varieties of a given crop species represent a valuable resource for the future, requiring adequate protection and characterization. We have addressed the structure and distribution of genetic variation in the melon germplasm, that harbors impressive variation in fruit size, shape, color and taste, as well as aroma and ripening physiology. We used DNA fingerprinting to quantify such variation, related it to morphological and agronomic traits, and portrayed melon taxonomy at the infra-specific level with such tools (refs. 13, 14, 15). Variation in plant and fruit morphology and in DNA profiles were analyzed in a set of 60 melon varieties from all over the world (Fig. 1). We described and analyzed the variation in fruit sugars and in acid invertase, an enzyme that is developmentally modulated to determine sucrose levels (ref. 14; Fig. 2), and showed that potentially useful genetic variation in all three sugars is found in "exotic" botanical variants of melon that are currently under-utilized in breeding. These studies continued earlier studies with Prof. Galun on inter-specific classification of the Genus Cucumis (refs. 1, 2). A pre-breeding project that attempts to utilize variation in shape, size and taste of melons for generating novel fruit types is running in our lab. For more information on the Melon Gallery Project (Fig. 3) please contact us. 

     

    Another project relates to the watermelon, Citrullus lanatus: using a small grant from the Israeli Gene Bank, we collected wild accessions of Citrullus in Israel, in order to characterize them in terms of genetic diversity and potential use for breeding (Fig. 4).  In addition, in the framework of a collaboration via Dr. Salih Kafkas of Chukrova University in Turkey, we applied molecular markers to characterize wild Pistacia species, that serve as rootstock for high value pistachio cultivars (refs. 20, 22-25).

     

    Genetic mapping in melon

    A melon genetic map was generated based on the F2 generation of the cross P.I. 414723 x cultivar TopMark (Fig. 5; ref. 19, 29). We also prepared a Recombinant Inbred Lines (RIL) collection from the same cross. The map included ~180 loci obtained by different techniques. Several markers anchored our linkage groups to those of more saturated reference maps.

     

    A great achievement of plant molecular biology involves cloning of disease resistance genes, responsible for pathogen recognition and signaling. We cloned and characterized resistance gene homologs (RGH) in melon. Together with the group of Drs. Pitrat and Dogimont at INRA and Prof. Gary Thompson in Little Rock we tested linkage between our clones and several disease and pest-resistance loci. These included Vat (aphid resistance), two Fusarium resistance loci, Fom-1 and Fom-2, and resistance to papaya ringspot virus (refs. 21, 26, 28, 33). Such markers are used as diagnostic tools to breed for insect and disease resistance (Fig. 6Fig. 7).  We focused on the Fom-1 /Prv locus and on the Zym loci (resistance to the zucchini yellow mosaic virus) and generated high resolution maps of these loci (ref. 33). Linked markers were used as starting points for a chromosome walk that culminated in cloning of the resistance genes (Fig. 7B; ref. 48); this was done in collaboration with Drs. Pitrat, Dogimont and Bendahmane at INRA and Dr. Katzir at A.R.O.

     

    Quantitative resistance to Fusarium oxysporum race 1.2 in melon

    Race 1.2 of melon Fusarium is controlled by multiple genes and is more difficult to manipulate in breeding. We have characterized a breeding line, BIZ (property of Zeraim Gedera Ltd.) that harbors strong and reliable resistance towards Israeli strains of race 1.2. We showed that two main recessive genes confer full resistance (Ref. 40) and began mapping them using QTL analysis.  We have used a GFP strain of the fungus to visualize the colonization of melon seedlings in vivo (Fig. 8), and observed quicker and higher expression of defense genes in the resistant seedlings, compared to susceptible ones (Ref. 44).

     

    More plant-pathogen and plant-pest interactions

    Arabidopsis-rhizoctonia interaction: During a Sabatical at CSIRO, Perth, West Australia (2002), I collaborated with Prof. Karam Singh and Dr. Rhonda Foley on interactions between Arabidopsis and the fungus Rhizoctonia, using the luciferase reporter system. We made real-time observations of the physical contact between the fungus and the living plant, which responds to the challenge by emitting bioluminescence (Fig. 9; ref. 30, 38).

     

    Plant response to broad mites: This project addresses plant-herbivore interactions, in collaboration with A.R.O. entomologists Dr. Victoria Sorocker. We studied the interaction of cucurbit crops with a serious pest, the broad mite. We described its damage at the microscopical level (Fig. 10), and documented the plant responses, including induction of defense genes (ref. 34). We used tomato mutants defective in defense signaling to demonstrate the importance of a defense hormone, jasmonic acid, in defense against broad mites. We have shown for the first time the broad mites are able to choose a favorable host and set up elegant bioassays to monitor the mite-plant interaction on detached leaves (Ref. 43). Presently, the three-party interaction between tomato, broad mite and the whitefly that serves as a vector in mite dispersal (Fig. 11), is being investigated in collaboration with Prof. L. Walling from Riverside, California.

     

    Molecular studies on sex expression in cucumber

    This project focuses on flower differentiation in plants that have a specific mechanism to separate their male and female organs. We have utilized two interesting features of cucumbers to approach such a complex developmental process. One is the availability of well characterized genotypes with striking differences in sex expression (Fig. 12). The second involves the possibility to physiologically induce dramatic sex changes by gibberellin and ethylene application (ref. B2, B3, B5). Using two contrasting genotypes, male and female cDNA libraries were prepared from very young floral buds, where "developmental decisions" are probably being made (ref. 36).

     

    Cucumber genes that govern floral architecture and determine sex-hormone synthesis and perception

    A family of three cDNAs that are homologous to the transcription factor AGAMOUS (that controls pistil and stamen formation in flowers) has been cloned and characterized (ref. 11). They probably are part of the flower's differentiation program after its fate has been determined by more "upstream" genes. A family of three ACC oxidase cDNAs, encoding the final step of ethylene synthesis, has been cloned (ref. 16). The role of ethylene in cucumber sex-modification is well established, and we studied the expression of these genes in relation to sex patterns of different cucumber genotypes. Distinct patterns of ACC oxidase transcripts in floral organs suggested localized, stage-specific roles for ethylene in floral organ differentiation (Fig. 12). In addition, we have cloned ethylene receptor-homologues from cucumber and analyzed their expression. In collaboration with other researchers in Israel (Dr. Zelcer, A.R.O.) and India (Dr. Ganapathy, Dr. Rajagopalan, Tiruchirappalli), we set-up cucumber transformation in our lab (Fig. 13; refs. 32, 35). A construct for over-expression of ERS, an ethylene receptor gene, was indeed shown to enhance femaleness of transgenic cucumbers, establishing the importance of ethylene sensitivity for sex expression (Fig. 14; ref. B5).

     

    We were also involved in map-based cloning of the cucumber sex determining genes. We prepared several genetic populations, each segregating for a different sex determining locus. In collaboration with INRA researcher Dr. Bendahmane, the Monoecious gene has been cloned using this approach. It was shown to encode an ACC synthase isoform that is expressed in the carpels of pistillate flowers, and inhibits the developing stamen (ref. 44). Together with theFemale gene cloned years ago by other groups, this finding greatly advanced our view on sex determination mechanism in cucumber. As a tool for functional characterization of cloned genes, we have prepared and tested a TILLING population for cucumber (Proceedings ref. 7; Fig. 15).

     

    Control of cucumber fruit set

    In the past two years we have begun to investigate the control of fruit set at the whole-plant level. Following fertilization, what factors determine whether an ovary will set fruit, or remain inhibited and senesce? Preliminary data relating to the "First-Fruit Inhibition phenomenon, being developmentally distinct from "regular senescence" has been obtained (Proceedings ref. 5, 8).

     

    Courses

    Course # 80-701 INTRODUCTION TO BIOLOGY

    2 hrs lecture, 1st year, 1st semester.

     

    Provides an introduction to biological principles and concepts such as membranes, biological macromolecules, prokaryotic and eukaryotic cells, multicellularity, genetic information,. An overview of bacteria, viruses, fungi and protists; a taxonomic survey of the plant kingdom from lower to higher plants. Major plant processes: photosynthesis, nitrogen assimilation, plant-water relationships, phloem transport, response to environmental stimuli.

     

     

    Course No. 80-225 PLANT PHYSIOLOGY

    Lecture: 3 hours a week, 2nd year, 2nd semester (jointly with Dr. Orit Shaul).

     

    The course covers major topics in Plant Biochemistry and Physiology. The scientific approaches and techniques that served to make the main discoveries in the field are emphasized. Relevance of physiological processes to Agriculture and Environmental Protection is discussed, and examples of Molecular studies based on Plant Physiology are given.

    Contents: Introduction: The Plant Kingdom, vegetal "principles of life", challenges of botanical research. Photosynthesis: thermodynamic and photochemical principles, light and dark reactions, chloroplast structure, photorespiration, adaptation to environmental changes, sucrose and starch synthesis. Plant-water relations: water potential and its components, water and mineral conduction in the soil-plant-atmosphere continuum, the photosynthesis-transpiration dilemma, stomatal action, response to drought stress. Transport of assimilates in the phloem. Nitrogen metabolism in plants. Introduction to growth and differentiation. Plant hormones: structure, assays, responses, mode of action. Photomorphogenesis: phytochrome and other photoreceptors, photoperiodic induction of flowering.

     

     

    Course # 80-329 PRINCIPLES OF PLANT MOLECULAR GENETICS AND BIOTECHNOLOGY

    2 hrs lecture + 2 hrs practice, 3rd year, 2nd semester

     

    Key-aspects of Plant Genetics are addressed, starting from the classical genetic level, required to understand the foundation of the more modern approaches, through somatic cell genetics and cytogenetics, down to molecular studies of the Plant Genome and Genetic Engineering.

    Contents: Introduction to the plant genome: nuclear genome size and composition, genomics approaches. The chromosomes: ploidy systems in plants, cytogenetic achievements in plant research and breeding. The chloroplast and the mitochondrial genomes in plants. Genome mapping and use of molecular markers in plant breeding. Map-based cloning. Plant tissue culture and its applications: protoplast and cell cultures, embryogenesis and organogenesis, haploid cultures, in vitro selection. Somatic cell fusions. Genetic engineering of plants: transformation methods. Overexpression and repression of plant genes; marker genes and reporter genes; examples of transgenic plants with agricultural potential.

    Practice involves reading and analysis of relevant scientific literature, genomics database mining and computing a genetic map, and visits to a plant tissue culture company and a seed company that applies molecular methods in breeding.

     

     

    Course # 80-491 UNDERGRADUATE STUDENTS SEMINAR    

     

    The course consist of 1-hour seminars, a series of presentations and discussions delivered by students on a current research topic in Plant Biology.

     

    MOLECULAR AND HORMONAL REGULATION OF PLANT DEVELOPMENT  (new Course planned for 2013-2014)

    2 hrs lecture, jointly with Dr. Hinanit Koltai and Dr. Vered Irihimovitch, ARO

     

     The course discusses major themes in plant development, related to leaf, root, flower and fruit induction and organogenesis. Hormonal signals and molecular mechanisms that orchestrate plant development are emphasized. Students are requested to present mini-seminars related to key research articles, as a basis for in depth discussion of modern methodologies and model plants employed in the field.

    Media

     More Pictures of Rafi: 1234

     

    • Our Group Photos: 

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    2011a2011b2011c2013

     

    • Our Group Cartoons:

     IrinaPremYariv&Zachi1Yariv&Zachi2ZachiMor1Mor2

    MichalRaniAvitalAnatHAvidaGolanYula

     

     A few Family Pictures:

    Ithaca 1992Yair's Bar-Mizva 2001Alps 2003Tamar's Bat-Mizva 2004

    Perth 2003abcdef , Cairns 2003Perl's 50th anniversary 2006ab

    Beijing 2006abBadaling 2006Yunnan 2006abcd

    Negev Desert  2007abCroatia 2008Metz 2008Jordan Valley 2008

    Paris 2008Noam 2008David 2007abYair 2008

    David 2009,Torino2012abcdRoma 2012Nova Scotia 2010abcde

    Hanukka 2012Succot 2012Lazarus Wedding 2012abc,  

    Tamar enrolls 2012ab, Japan 2012abcdef,ghij

    Noam Bar Mizva abcd 

    Last Updated Date : 27/03/2022