e-mail: reinhard.jetter@botany.ubc.ca
office phone: (604) 822-2477
lab phone: (604) 822-8124

Professor, Dept. of Botany and Chemistry
Canadian Research Chair in Plants Natural Products Chemistry
Ph.D. Botany (1993) Univ. of Kaiserslautern (Germany);
Postdoctoral Fellow (1994-96) Washington State Univ.;
Research Associate (1996-2003) Univ. of Wuerzburg (Germany).

These are the biological questions that motivate the research in my lab. In order to answer them, we employ molecular genetic, microscopic and eco-physiological (as well as biochemical) techniques to study plant surfaces. Depending on the individual research question, we use Arabidopsis thaliana and an array of other plant species as models for our studies.

In particular, we investigate cuticular waxes, which coat most above-ground plant organs. We explore both the biological functions of these waxes and the molecular biology underlying their formation. We investigate wax functions such as their central physiological role to seal the plant tissue against water loss and their ecological function as a first line of defence against herbivores. On the other end of the spectrum of our biological interests, we investigate the molecular machinery – the genes and enzymes – plants employ to generate their wax coatings.

We are using Gas Chromatography and Mass Spectrometry to separate the complex mixtures of plant waxes and identify their constituents. My group has investigated surfaces of more than 50 plant species and identified more than 500 different wax constituents (fatty acid derivatives, triterpenoids and phenolics). Microscale syntheses of authentic standards were used to confirm structures after they had been assigned by spectroscopy. To date, we have elucidated the structures of more than 200 novel natural products.
Amongst others, homologous series of lactones, hydroxyaldehydes, and alkanediols were identified. These compound classes were found to share the special arrangement of two functional groups in 1,3-, 1,5-, 1,7-, 1,9-, or 1,11-positions. We therefore hypothesize that these compounds are polyketides, and that their biosynthesis proceeds via special elongation pathways. This idea is currently being tested by experiments involving the cloning and characterization of relevant candidate enzymes.

3. Wax biosynthesis in Arabidopsis thaliana We are working on a number of projects using the model plant Arabidopsis thaliana to elucidate the pathways leading to the formation of cuticular waxes. In collaboration with the labs of Lacey Samuels and Ljerka Kunst, we have investigated a number of genes and their enzyme products. We performed the wax analyses of mutant plants and of transgenic yeast to help characterize the biochemical function of the enzymes. In a similar way, we were able to find and characterize the first proteins involved in export of waxes from the biosynthesizing cells towards the plant surface.

5. Plant-ant interactions The stems of many Macaranga ant-plants (Euphorbiaceae) are densely covered with microscopic wax crystals. Symbiotic ant species can adhere to and walk on these vertical surfaces. In contrast, the crystals are slippery for generalist insect species and they are excluded from higher parts of the plants. In this system surface wax crystals consequently function as a mechanical barrier that protects specialist Macaranga partners against competition by other ant species. We currently investigate the mechanisms causing the slipperiness for diverse ant species. For this purpose, the physical properties of the plant surfaces have to be assessed and related to their chemical composition. Based on these data, model surfaces with corresponding characteristics can then be prepared. In a close collaboration, the adhesive organs and the processes of movement both of specialist Macaranga partner ants and their generalist competitors are investigated in the lab of Walter Federle (University of Cambridge) [http://www.zoo.cam.ac.uk/ZOOSTAFF/federle.html].

6. Slippery surfaces on carnivorous plants

	Plants in the carnivorous genus Nepenthes obtain a substantial nutrient supply by trapping insects in highly modified leaves. A broad zone of the inner surface of these pitchers is densely covered with wax crystals on which most insects lose their footing. This slippery wax surface, capturing prey and preventing its escape from the trap, plays a pivotal role in the carnivorous syndrome. To understand the mechanism of slipperiness, we want to characterize the ultrastructure and the physico-chemical properties of the wax crystals in pitchers of various Nepenthes species. Scanning electron microscopy has revealed that characteristic wax platelets protrude perpendicularly from the surface. Methods have been developed that allow the mechanical removal of these wax crystals from the pitcher surface.
	We have shown that the sampling was selective for the outermost part of the wax crystals, relevant for plant-insect-interactions, and can now for the first time directly assess the quantities of all compounds involved in crystal formation.
These chemical results will be combined with data describing the biomechanical properties of the crystals.

Courses Taught:

CHEM 233 - Organic Chemistry for Non-Majors

CHEM 333 - Spectroscopic Techniques in Organic Chemistry

BIOL 423 - Plant Stress Ecophysiology

BOTA 501 - Seminar Studies in Botany

BOTA 546 - Plant Lipid Biochemistry
   

Research Team:

Current Team:

Christopher Buschhaus (Graduate Student, Botany)
Stephen Greer (Post Doctoral Fellow)
Xiufeng Ji (Graduate Student, Chemistry)
Rui Liu (Graduate Student, Botany)
Clare Scott (Graduate Student, Chemistry)
Zhonghua Wang (Post Doctoral Fellow)
Miao Wen (Graduate Student, Chemistry)

Former group members: Jason Au Assad Dharsi Megan Gao Ortwin Guhling Shagha Kayem Christian Kinzler Christine Lai Torsten Vielhaber Bangjun Wang Trevor Yeats

Yeats, T.H.; Buda, G.J.; Wang, Z.; Chehanovsky, N.; Moyle, L.C.; Jetter, R.; Schaffer, A.A.; Rose, J.K.C. (2012) The fruit cuticles of wild tomato species exhibit architectural and chemical diversity, providing a new model for studying the evolution of cuticle function. The Plant Journal 69, 655-666.

Bessire, M.; Borel, S.; Fabre, G.; Carraça, L.; Efremova, N.; Yephremov, A.; Cao, Y.; Jetter, R.; Jacquat, A.-C.; Métraux, J.-P.; Nawrath, C. (2011) A member of the PDR family of ABC transporters is required for the formation of a functional cuticle in Arabidopsis. Plant Cell 23, 1958-1970.

Buschhaus, C.; Jetter, R. (2011) Composition differences between epicuticular and intracuticular wax substructures: How do plants seal their epidermal surfaces? Journal of Experimental Botany 62, 841-853.

Wang, Z.; Guhling, O.; Yao, R.; Li, F.; Yeats, T.H. Rose, J.K.C.; Jetter, R. (2011) Two oxidosqualene cyclases responsible for biosynthesis of tomato fruit cuticular triterpenoids. Plant Physiology 155, 540-552.

Jetter, R; Sodhi, R. (2011) Chemical composition and microstructure of waxy plant surfaces: triterpenoids and fatty acid derivatives on leaves of Kalanchoe daigremontiana. Surface and Interface Analysis 43, 326-330.

Wang, Z.; Yeats, T.; Han, H.; Jetter, R. (2010) Cloning and characterization of oxidosqualene cyclases from Kalanchoe daigremontiana: enzymes catalyzing up to ten rearrangement steps yielding friedelin and other triterpenoids. Journal of Biological Chemistry 285, 29703-29712.

Adato, A.; Mandel, T.; Mintz-Oron, S.; Venger, I.; Levy, D.; Yativ, M.; Dominguez, E.; Wang, Z.; DeVos, R.C.H.; Jetter, R.; Schreiber, L.; Heredia, A.; Rogachev, I.; Aharoni, A. (2009) Fruit-surface flavonoid accumulation in tomato is controlled by a SlMYB12-regulated transcriptional network. PLoS Genetics 5, 12.

van Maarseveen, C.; Jetter, R. (2009) Composition of the epicuticular and intracuticular wax layers on Kalanchoe daigremontiana (Hamet et Perr. de la Bathie)leaves. Phytochemistry 70, 899-906.

Wen, M.; Jetter, R. (2009) Composition of secondary alcohols, ketones, alkanediols and ketols in Arabidopsis thaliana cuticular waxes. Journal of Experimental Botany 60, 1811-1821.

Agrawal, A.A.; Sparks, J.; Jetter, R.; Salminen, J.-P.; Goldstein, J.B.; Freitag, A.E.; Fishbein, M. (2009) Phylogenetic ecology of leaf surface traits in the milkweeds (Asclepias spp.): chemistry, ecophysiology, and insect behavior. The New Phytologist 183, 848-867.

deBono, A.; Yeats, T.; Rose, J.K.C.; Bird, D.; Jetter, R.; Kunst, L.; Samuels, A.L. (2009) LTPG is a glycosylphosphatidylinositol-anchored lipid transfer protein required for export of lipids to the plant surface. Plant Cell 21, 1230-1238.

van Maarseveen, C.; Han, H.; Jetter, R. (2009) Development of the cuticular wax during growth of Kalanchoe daigremontiana (Hamet et Perr. de la Bathie)leaves. Plant Cell and Environment 32, 73–81.

Li, F.; Wu, X.; Lam, P.; Bird, D.; Zheng, H; Samuels, L.; Jetter, R.; Kunst L. (2008) Identification of the wax ester synthase/acyl-CoA:diacylglycerol acyltransferase WSD1 required for stem wax ester biosynthesis in Arabidopsis thaliana. Plant Physiology 148: 97-107.

Mintz-Oron, S.; Mandel, T.; Rogachev, I.; Feldberg, L.; Lotan, O.; Yativ, M.; Wang, Z.; Jetter,R.; Venger, I.; Adato, A.; Aharoni, A. (2008) Gene expression and metabolite analysis in tomato fruit surface tissues. Plant Physiology 147, 823-851.

Jetter, R.; Kunst, L. (2008) Plant surface lipid biosynthetic pathways and their utility for metabolic engineering of waxes and hydrocarbon biofuels. The Plant Journal 54, 670-683.

Samuels, L.; Kunst, L.; Jetter, R. (2008) Sealing plant surfaces: cuticular wax formation by epidermal cells. Annual Review of Plant Biology 59, 683-707.

Ji, X.; Jetter, R. (2008) Localization of very long chain alkylresorcinols in the cuticular wax of rye (Secale cereale L.) leaves. Phytochemistry 69, 1197-1207.

Yu, M.M.; Konorov, S.O.; Schulze, H.G.; Blades, M.W.; Turner, R.F.B.; Jetter, R. (2008) In situ analysis by microspectroscopy reveals triterpenoid compositional patterns within leaf cuticles of Prunus laurocerasus. Planta 227, 823–834.

Greer, S.; Wen, M.; Bird, D; Wu, X.; Samuels, L.; Kunst, L.; Jetter, R. (2007) The cytochrome P450 CYP96A15 is the mid-chain alkane hydroxylase responsible for formation of secondary alcohols and ketones in stem cuticular wax of Arabidopsis thaliana. Plant Physiology 155, 653-667.

Buschhaus, C.; Herz, H.; Jetter, R. (2007) Chemical composition of the epicuticular and intracuticular wax layers on adaxial sides of Rosa canina L. leaves. Annals of Botany 100, 1557-1564.

Hovav, R.; Chehanovsky, N.; Moy, M.; Jetter, R.; Schaffer, A. (2007) Map-based cloning of a gene (Cwp1), silenced during Solanum evolution, which causes cuticle microfissuring and dehydration when expressed in tomato fruit. The Plant Journal 52, 627-639.

Buschhaus, C.; Herz, H.; Jetter, R. (2007) Chemical composition of the epicuticular and intracuticular wax layers on the adaxial side of Ligustrum vulgare leaves. The New Phytologist 176, 311-316.

Wen, M.; Jetter, R. (2007) Novel very-long-chain hydroxyaldehydes from the cuticular wax of Taxus baccata needles. Phytochemistry 68, 2563-2569.

Bird, D.; Beisson, F.; Brigham, A.; Shin, J.; Greer, S.; Jetter, R.; Kunst, L.; Wu, X.; Yephremov, A.; Samuels, L. (2007) Characterization of Arabidopsis WBC11/ABCG11, an ATP binding cassette (ABC) transporter that is required for cuticular lipid secretion. The Plant Journal 52, 485-498.

Yu, M.M.L.; Schulze, G.; Jetter, R.; Blades, M.L.; Turner, R.F.B. (2007) Raman microspectroscopic studies of triterpenoids found in plant cuticles. Applied Spectroscopy 61, 32-37.

Riedel, M.; Eichner, A.; Meimberg, H.; Jetter, R. (2007) Chemical composition of epicuticular wax crystals on the slippery zone in pitchers of five Nepenthes species and hybrids. Planta 225, 1517-1534.

Lai, C.; Kunst, L.; Jetter, R. (2007) Composition of alkyl esters in the cuticular wax on inflorescence stems of Arabidopsis thaliana cer mutants. The Plant Journal 50, 189-196.

Rowland, O.; Zheng, H.; Hepworth, S.R.; Lam, P.; Jetter, R.; Kunst, L. (2006) CER4 encodes an alcohol-forming fatty acyl-CoA reductase involved in cuticular wax production in Arabidopsis. Plant Physiology 142, 866-877.

Wen, M.; Au, J.; Gniwotta, F.; Jetter, R. (2006) Novel very-long-chain secondary alcohols and alkanediols in cuticular waxes of Pisum sativum leaves. Phytochemistry 67, 2494-2502.

Wen, M.; Buschhaus, C.; Jetter, R. (2006) Nanotubules on plant surfaces: Formation and chemical composition of epicuticular wax crystals on needles of Taxus baccata L. Phytochemistry 67, 1808-1817.

Guhling, O.; Hobl, B.; Yeats, T.; Jetter, R. (2006) Cloning and characterization of a lupeol synthase involved in the synthesis of epicuticular wax crystals on stem and hypocotyl surfaces of Ricinus communis. Archives of Biochemistry and Biophysics 448, 60-72.

Suh, M.C.; Samuels, A.L.; Jetter, R.; Kunst, L.; Pollard, M.; Ohlrogge, J.; Beisson, F. (2005) Cuticular lipid composition, surface structure, and gene expression in Arabidopsis stem epidermis. Plant Physiology 139, 1649-1665.

Guhling, O.; Kinzler, C.; Dreyer, M.; Bringmann, G.; Jetter, R. (2005) Surface composition of myrmecophilic plants: cuticular wax and glandular trichomes on leaves of Macaranga tanarius (Euphorbiaceae). Journal of Chemical Ecology 31, 2325-2343.

Gniwotta, F.; Vogg, G.; Gartmann, V.; Carver, T.L.W.; Riederer, M.; Jetter, R. (2005) What do microbes encounter at the plant surface? Chemical composition of Pisum sativum leaf cuticular waxes. Plant Physiology 139, 519-530.

Samuels, L.; Jetter, R.; Kunst, L. (2005) First steps in understanding the export of lipids to the plant cuticle. Plant Biosystems 139, 65-68.

Pighin, J.A.; Zheng, H.; Balakshin, L.J.; Goodman, I.P.; Western, T.L.; Jetter, R.; Kunst, L.; Samuels, A.L. (2004) Plant cuticular lipid export requires an ABC transporter. Science 306, 702-704.

Aharoni, A.; Dixit, S.; Jetter, R.; Thoenes, E.; Van Arkel, G.; Pereira, A. (2004) The SHINE clade of AP2 domain transcription factors activate wax biosynthesis, alter cuticle properties and confer drought tolerance when overexpressed in Arabidopsis. Plant Cell 16, 2463–2480.

Vogg, G.; Fischer, S.; Leide, J.; Emmanuel, E.; Jetter, R.; Levy, A.A.; Riederer, M. (2004) Tomato fruit cuticular waxes and their effects on transpiration barrier properties: functional characterisation of a mutant deficient in a very-long-chain fatty acid b-ketoacyl-CoA synthase. Journal of Experimental Botany 55, 1401-1410.

Riedel, M.; Eichner, A.; Jetter, R. (2003) Slippery surfaces of carnivorous plants: composition of epicuticular wax crystals in Nepenthes alata Blanco pitchers. Planta 218, 87-97.

Vermeer, C.P.; Nastold, P.; Jetter, R. (2003) Homologous very-long-chain 1,3-alkanediols and 3-hydroxyaldehydes in leaf cuticular waxes of Ricinus communis L. Phytochemistry 62, 433-438.