Expression Analysis of a Glucose Oxidase Transgene in Tobacco

Author

Jordan Burt, Ouachita Baptist UniversityFollow

Date of Award

2015

Document Type

Thesis

Department

Biology

First Reader

Dr. Nathan Reyna

Second Reader

Dr. Angela Douglass

Third Reader

Dr. Barbara Pemberton

Abstract

Glucose oxidase (GOX) is an enzyme in plants that catalyzes the oxidation of glucose to hydrogen peroxide and Glucono delta-lactone[5]. We have expressed GOX under the control of an estrogen inducible system, XVE, to analyze the gene's expression under this system compared to a system using the 35s system. The 35s system contains a promoter that constitutively turns on the GOX gene in the Nicotiana tabacum plant which causes the gene to always be turned on. Leaf disc assays were performed with discs from 35s, XVE, and also wild type plants (not containing the GOX gene) in order to extract protein to show GOX expression. With 35s and wild type acting as controls, the XVE discs were subjected to both water and 100 uM estradiol applications for differing amounts of time (24 and 48 hours). Western blots displayed results exhibiting different expression of protein in XVE:GOX discs when subjected to the estradiol versus water solution. Nicotiana tabacum therefore shows considerable induction within as little as 48 hrs. The XVE plants were subjected to other assays to confirm the inducibility seen in the leaf disc assays. Discs taken from both water and estradiol applications were taken and placed in glucose for 8 days causing stress on the plants which could be viewed by the loss of the green color. The discs that were effectively induced by the estradiol showed greater effects due to the glucose. Along with being placed in glucose, discs were also placed in a starch media containing glucose for 7 days. Discs demonstrated blackening in the media within several hrs. These results suggest that the XVE system used in the Nicotiana tabacum shows and ability to be induced with 100 uM estradiol and alters the GOX expression in the plant.

Recommended Citation

Burt, Jordan, "Expression Analysis of a Glucose Oxidase Transgene in Tobacco" (2015). Honors Theses. 184.
https://scholarlycommons.obu.edu/honors_theses/184