Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Javascript disabled

Please enable Javascript support in your browser to use this application.

Instructions on how to enable JavaScript on different browsers can be found here: http://www.google.com/support/bin/answer.py?answer=23852.

[edit this page]

Ralph, S.G. et al.

Aminocyclopropane carboxylic Acid synthase is a regulated step in ethylene-dependent induced conifer defense. Full-length cDNA cloning of a multigene family, differential constitutive, and wound- and insect-induced expression, and cellular and subcellular localization in spruce and douglas fir.

In conifer stems, formation of chemical defenses against insects or pathogens involves specialized anatomical structures of the phloem and xylem. Oleoresin terpenoids are formed in resin duct epithelial cells and phenolics accumulate in polyphenolic parenchyma cells. Ethylene signaling has been implicated in the induction of these chemical defenses. Recently, we reported the cloning of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) from spruce (Picea spp.) and Douglas fir (Pseudotsuga menziesii). ACO protein was constitutively expressed in Douglas fir and only weakly induced upon wounding. We now cloned seven full-length and one near full-length cDNA representing four distinct 1-aminocyclopropane-1-carboxylic acid synthases ( ACS; ACS1, ACS2, ACS3, and ACS4) from spruce and Douglas fir. Cloning of ACS has not previously been reported for any gymnosperm. Using gene-specific, quantitative real-time polymerase chain reaction, we measured constitutive expression for the four ACS genes and the single-copy ACO gene in various tissues of Sitka spruce (Picea sitchensis) and in white spruce (Picea glauca) somatic embryos. ACO and ACS4 were ubiquitously expressed at high levels; ACS1 was predominantly expressed in developing embryos and ACS2 and ACS3 were expressed only at very low levels. Insect attack or mechanical wounding caused strong induction of ACS2 and ACS3 in Sitka spruce bark, a moderate increase in ACO transcripts, but had no effect on ACS1 and ACS4. ACS protein was also strongly induced following mechanical wounding in Douglas fir and was highly abundant in resin duct epithelial cells and polyphenolic parenchyma cells. These results suggest that ACS, but not ACO, is a regulated step in ethylene-induced conifer defense.[1]

References

Aminocyclopropane carboxylic Acid synthase is a regulated step in ethylene-dependent induced conifer defense. Full-length cDNA cloning of a multigene family, differential constitutive, and wound- and insect-induced expression, and cellular and subcellular localization in spruce and douglas fir. Ralph, S.G., Hudgins, J.W., Jancsik, S., Franceschi, V.R., Bohlmann, J. Plant Physiol. (2007) [Pubmed]

Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenes Open Access Licence Privacy Policy Terms of Use

[search][advanced]