Your browser does not support JavaScript!

Home    Collections    Type of Work    Post-graduate theses  

Post-graduate theses

Current Record: 4628 of 4793

Back to Results Previous page
Next page
Add to Basket
[Add to Basket]
Identifier uch.biology.msc//2000alexandrou
Title Δημιουργία γενετικά τροποποιημένων φυτών καπνού, που υποεκφράζουν και υπερεκφράζουν τη μεσοφυλλική καταλάση, CAT1
Alternative Title Modification of Catalase(CAT1) expression in transgenic tabacoo plants.
Creator Alexandrou, Dimitrios P
Abstract Biotic and abiotic factors are known to induce generation of active oxygen species (AOS). Scavenging of AOS is implemented by a combination of enzymic and non-enzymic mechanisms. Catalase is considered to be of great significance, since it is one of the enzymes scavenging H2O2. It comprises several isoenzymes that reside mainly in the peroxisomal matrix and exhibit a tissue-specific distribution. We used tobacco as a model system to investigate the effects of altered catalase levels on important phenomena, such as morphogenic expression, hypersensitive response (HR) and systemic acquired resistance (SAR). There is strong evidence indicating that the low viability and regenerating potential of grapevine protoplasts, could originate, at least partially, from the oxidative burst and the altered redox state of the cells, which are induced by the procedures of protoplast isolation. Several lines of transgenic tobacco plants were developed, expressing sense and antisense Cat1 trangenes. CAT-1 is considered to be the exclusive isozyme in mesophyll cells. Constructs that were used for the Agrobacterium-mediated transformation contained fragments of Cat1 homologues, derived from closely related species, in antisense orientation under the control of 35S CaMV promoter. The complete Cat1 cDNA clone in sense orientation driven by the35S CaMV promoter, was also used to increase endogenous catalase. The obtained plants exhibit a minimum 40% reduction in catalase activity, compared to the untransformed. In addition, the identities of the selected transgenic plants were verified by Southern analysis, catalase immunodetection and Northern hybridizations. Ascorbate peroxidase (APO), glutathione reductase (GR) and superoxide dismutase (SOD) activities were also examined in the selected plants.
Issue date 2000-11-01
Date available 2000-10-17
Collection   Faculty/Department--Faculty of Sciences and Engineering--Department of Biology--Post-graduate theses
  Type of Work--Post-graduate theses
Permanent Link Bookmark and Share
Views 30

Digital Documents
No preview available

View document
Views : 4