Resins induced terpene

To study more precisely the function of induced terpene resins in defense, it is necessary to develop a method to manipulate terpene formation without aflecting other possible defenses. For this purpose, we initiated a long-term study of the molecular biology of induced terpene biosynthesis in P. abies. The basic outline of terpene formation is well understood (Fig. 1.4). The C5 building blocks of all terpenes are synthesized via the mevalonate pathway (localized in the cytosol) from... 

Based on our current knowledge, the chemistry of induced defenses in P. abies and other woody plants is not materially different from that of herbaceous plants. Terpenes, phenolics, and chitinases are all common metabolites in herbs, and in many cases are inducible upon herbivory or pathogen infection. However, the presence of inducible terpene resins is a special feature of conifers. In the rest of the plant kingdom, mixtures of terpenes accumulate in resin ducts, cavities or glandular hairs of many taxa, but are usually not reported to be inducible. Moreover, the long induction time of conifer resin also sets it apart from other induced defenses. 

Our recent research suggests organ-, tissue-, and cell-specific localization of constitutive and induced terpenoid defense pathways in conifers. For example, linalool synthase (PaTPS-Lin) seems to be preferentially expressed in needles of Norway spruce and Sitka spruce with little or no expression in sterns. ft is also likely that expression of PaTPS-Lin in spruce needles is not associated with resin ducts but could reside in other cells involved with induced terpenoid emission. In contrast, we can speculate that most other mono-TPS and di-TPS are associated with epithelial cells of constitutive and induced resin ducts. The possible localization of conifer sesqui-TPS is difficult to predict. Furthermore, the exact spatial and temporal patterns of terpenoid pathway gene expression associated with traumatic resin duct development in the cambium zone and outer xylem remain to be studied at the tissue and cell level. In situ hybridization and immuno-localization of TPS will address these open questions. These methods have worked well in identifying cell type specific gene and protein expression of alkaloid formation in opium poppy Papaver somniferum) As the biochemistry of induced terpene defenses and the development of traumatic resin ducts have been well described in spruce, this system is ideal for future studies of tissue- and cell-specific localization of transcripts and proteins associated with oleoresin defense and induced volatile emissions in conifers. In addition, the advent of laser dissection microscopy techniques presents a fascinating means by which to further address RNA and protein analysis in a tissue-and cell-specific manner. These techniques, when applied to the cambium zone, xylem mother cells, and the epithelial cells that surround traumatic resin ducts, and will allow a temporal and spatial analysis of cellular functions occurring in the traumatic resin response. 

FALDT, J., MARTIN, D., MILLER, B., RAWAT, S., BOHLMANN, J., Traumatic resin defense in Norway spruce Picea abies) Methyl jasmonate-induced terpene... 

Faldt J, Martin D, Miller B, Rawat S, Bohlmann J (2003) Traumatic resin defense in Norway spruce (Picea abies). methyl jasmonate-induced terpene synthase gene expression, and cDNA cloning and functional characterization of (+)-3-carene synthase. Plant Mol Biol 51(1) 119-133... 

In this review, we examine the induced chemical defenses of P. abies, defenses whose levels increase following herbivore or pathogen attack. Induced defenses have attracted much attention in recent years because of their widespread occurrence in plants and their usefulness as subjects for study. Here, we cover the induction of several different classes of induced defenses in P. abies, including terpene-containing resins, phenolic compounds, and chitinases. Our focus is not only on their defensive roles, but also on how the levels of these compounds may be manipulated by biochemical and molecular methods while minimizing other phenotypic changes. Manipulation of defense compoimds in intact plants is a valuable approach to assessing their value to the plant. 

Fig. 4.9 Feedback among tree and beetle population processes involving terpenes. Beetles enter trees, produce pheromones, and deplete host resins, and trees respond with induces accumulation of monoterpenes that inhibit beetle entry, communication, and tunneling, as in Figure 3. However, beetle host acceptance behavior is plastic, and responds to interactions of regional (population phase) and local (plant surface) population density (Population Size Range of Monoterpenes Eliciting...

Mono- and sesquiterpenes are the main constituents of the essential oils, while the other terpenes are constituents of balsams, resins, waxes, and rubber. Oleoresin is a roughly equal mixture of turpentine (85 % Cio-monoterpenes and 15 % C15- sesquiterpenes) and rosin (C2o-diterpene) that acts in many conifer species as a toxic material to invading insects and their pathogenic fungi [12]. A number of angiosperm species have inducible terpenoid defensive compounds (phytoalexins) [13]. These include both sesquiterpenoid and diterpenoid t)pes. Isoprenoid units are also found within the framework of other natural molecules. Thus, indole alkaloids, several quinones (vitamin K), alcohols (vitamin E, vitamin A formed from p-carotene), phenols, and isoprenoid alcohols (also known as terpenols or polyprenols) also contain terpenoid fragments. The biogenesis. 

A tackifier is a component to provide initial tackiness to adhesives. The compatibility of the tackifier to the main components is very important to increase the tackiness without degradation of the adhesive mixture. For that purpose, natural resins such as rosin and dammar, modified rosins such as coumarone-indene resin, polymerized rosin, hydrogenated rosin and rosin ester, and polyterpene resin are used. Recently, alkylphenol resins, terpene phenol resins, and xylene resins are out of use because of their hazardous nature inducing sick building syndrome. 

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