Theses and Dissertations - UTB/UTPA

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Michael Persans

Second Advisor

Dr. Megan Keniry

Third Advisor

Dr. Robert Gilkerson


In this study the expression of oxidative stress response (OSR) proteins in nonaccumulator and hyperaccumulator plant species of the Brassicaceae family were characterized. Oxidative stress was induced via nickel treatment and proteins were characterized through western blotting and image analysis. Statistical analysis indicated that the nonaccumulator species Arabidopsis thaliana significantly decreased catalase (CAT), glutathione reductase (GR), copper/zinc-dependent superoxide dismutase (Cu/ZnSOD), iron-dependent SOD (FeSOD), manganese-dependent SOD (MnSOD) and metal tolerance protein 1 (MPT1) expression in response to Ni-treatment. The hyperaccumulator species Thlaspi montanum variety montanum displayed either no significant change or a significant increase in OSR regulation following Ni-treatment with the exception of CAT. Overall, the nonaccumulator group displayed a significant decrease in total OSR regulation following Ni-treatment as compared to the other groups. These results suggest that the sustained expression of OSR proteins during oxidative stress may be one of the mechanisms that influence metal tolerance in hyperaccumulator plant species.


Copyright 2015 Luis M. De Santiago. All Rights Reserved.

Granting Institution

University of Texas-Pan American

Included in

Biology Commons