Metabolic engineering of hydroxycinnamic acid amide in nictoiana tabacum

Simple item page
dc.contributor.advisorFacchini, Peter J.
dc.contributor.authorHagel, Jillian M.
dc.date.accessioned2005-08-16T17:01:10Z
dc.date.available2005-08-16T17:01:10Z
dc.date.issued2004
dc.descriptionBibliography: p. 86-101en
dc.descriptionSome pages are in colour.en
dc.description.abstractFeruloyltyramine and 4-coumaroyltyramine participate in the defense of plants against pathogens through their extracellular peroxidative polymerization, which is thought to reduce cell wall digestibility or otherwise inhibit fungal growth. Hydroxycinnamoyl­CoA:tyramine N-(hydroxycinnamoyl)transferase (THT) and tyrosine decarboxylase (TYDC) are purported to play key roles in the stress-induced regulation of tyramine­derived hydroxycinnamic acid amide (HCAAT) biosynthesis. Transgenic tobacco (Nicotiana tabacum cv Xanthi) was engineered to constitutively express tobacco THT. A T₁ plant over-expressing THT was crossbred with T₁ tobacco expressing opium poppy TYDC2 to produce a T₂ line with elevated THT and TYDC activities compared with wild type plants. The effects of an independent increase in TYDC or THT activity, or a dual increase in both TYDC and THT on the cellular pools of HCAAT pathway intermediates and the accumulation of soluble and cell wall-bound feruloyltyrarnine and 4-coumaroyltyramine were examined. In roots, THT and TYDC activities were not substantially altered in transgenic lines beyond their relatively high wild type levels; thus, no changes in HCAAT precursor or product levels were detected. In leaves, increased TYDC activity resulted in a larger cellular pool of tyramine, and lower levels of phenylalanine. In contrast, elevated THT activity reduced tyramine levels. HCAAT levels were low in healthy leaves, but were induced in response to wounding and accumulated around wound sites. Similarly, endogenous THT and TYDC activities were wound-induced. The initial rate of wound-induced HCAAT accumulation was highest in transgenic plants with elevated THT and TYDC activities. These results show that both THT and TYDC exert partial and synergistic control over the flux of intermediates involved in HCAAT biosynthesis under some conditions.en
dc.format.extentxiv, 101 leaves : ill. ; 30 cm.en
dc.identifier.citationHagel, J. M. (2004). Metabolic engineering of hydroxycinnamic acid amide in nictoiana tabacum (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/10923en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/10923
dc.identifier.isbn049403758Xen
dc.identifier.lccAC1 .T484 2004 H335en
dc.identifier.urihttp://hdl.handle.net/1880/41569
dc.language.isoeng
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.titleMetabolic engineering of hydroxycinnamic acid amide in nictoiana tabacum
dc.typemaster thesis
thesis.degree.disciplineBiological Sciences
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameMaster of Science (MSc)
ucalgary.item.requestcopytrue
ucalgary.thesis.accessionTheses Collection 58.002:Box 1505 520492022
ucalgary.thesis.notesUARCen
ucalgary.thesis.uarcreleaseyen
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
2004_Hagel.pdf
Size:
44.43 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Legacy Theses