Bethany K. Zolman
Bethany K. Zolman
Assistant Professor
Phone: (314) 516-6205
Fax: (314) 516-6233
E-mail: zolmanb@umsl.edu
Education
B.S., 1997, Biology and Chemistry, Valparaiso University, Valparaiso, IN
Ph.D., 2002, Biochemistry and Cell Biology, Rice University, Houston, TX
Research Interests
My research focuses on peroxisomal function and its role in auxin metabolism
in the model plant Arabidopsis thaliana. I am studying the role
of indole-butyric acid (IBA) in auxin response and its relationship to the
principle auxin, indole-acetic acid (IAA). IBA is used widely in horticultural
settings because of its efficacy at inducing secondary roots on cuttings,
but the molecular mechanisms of IBA action are unknown. One hypothesis is
that IBA functions as a “slow-release” form of IAA, providing
free IAA for root intiation. Our results indicate this process may occur
in a pathway similar to fatty acid ß-oxidation in peroxisomes.
I have taken a genetic approach to elucidate the mechanisms of IBA function. My work has focused on two groups of IBA-response mutants:
1) Mutants defective in peroxisomal biogenesis or function. These mutants have defects in peroxins, which disrupt peroxisomal biogenesis or import, or in proteins acting within the peroxisome matrix, affecting specific pathways including fatty acid ß-oxidation and valine catabolism.
2) Mutants with IBA-response defects. These mutants do not have general peroxisome-defective phenotypes, indicating they may be defective in enzymes that act specifically on IBA.
Future work using genetics, cell biology, and biochemistry will reveal how IBA action is important for auxin responses in plants, the enzymes that convert IBA to IAA, and may eventually allow manipulation of species that do not effectively respond to IBA. In addition, this work provides an unbiased approach to explore the specifics of peroxisomal fatty acid metabolism in plants.
PublicationsZolman, B.K., Martinez, N., Millius, A., Adham, A.R., and Bartel, B. (2008) Identification and Characterization of Arabidopsis Indole-3-Butyric Acid Response Mutants Defective in Novel Peroxisomal Enzymes. Genetics. 180:237-251
Delker, C.*, Zolman, B.K.*, Miersch, O., and Waternack, C. (2007) Jasmonate biosynthesis in Arabidopsis thaliana requires peroxisomal beta-oxidation enzymes - Additional proof by properties of pex6 and aim1. Phytochem. 68, 1642-1650.
Zolman, B.K., Nyberg, M., and Bartel, B. (2007) IBR3, a novel peroxisomal acyl-CoA dehydrogenase-like protein required for indole-3-butyric acid response. Plant Mol Biol. 64, 59-72.
Zolman, B.K., Monroe-Augustus, M., Silva, I.D., and Bartel, B. (2005) Identification and functional characterization of Arabidopsis PEROXIN4 and the interacting protein PEROXIN22. Plant Cell 17, 3422-3435.
Adham, A.R., Zolman, B.K., Millius, A., and Bartel, B. (2005) Mutations in Arabidopsis thaliana acyl-CoA oxidase genes reveal overlapping and distinct roles in ß-oxidation. Plant J. 41, 859-874.
Zolman, B.K. and Bartel, B. (2004) An Arabidopsis indole-3-butyric acid-response mutant defective in PEROXIN6, an apparent ATPase implicated in peroxisomal function. Proc. Natl. Acad. Sci. USA 101, 1786-1791
Monroe-Augustus, M., Zolman, B.K., and Bartel, B. (2003) IBR5, a dual-specificity phosphatase-like protein modulating auxin and abscisic acid responsiveness in Arabidopsis. Plant Cell 15, 2979-2991.
Bartel, B., LeClere, S., Magidin, M., and Zolman, B.K. (2001) Inputs to the active indole-3-acetic acid pool: de novo synthesis, conjugate hydrolysis, and indole-3-butyric acid ß-oxidation. J. Plant Growth Regul. 20, 198-216. (review article)
Zolman, B.K., Silva, I.D., and Bartel, B. (2001) pxa1, an Arabidopsis ß-oxidation mutant, is defective in a protein required for the peroxisomal import of both fatty acids and indole-3-butryic acid. Plant Physiol. 127, 1266-1278. (featured on the cover)
Zolman, B.K., Monroe-Augustus, M., Thompson, B., Hawes, J.W., Krukenberg K.A., Matsuda, S.P.T., and Bartel, B. (2001) chy1, an Arabidopsis mutant with impaired ß-oxidation, is defective in a peroxisomal ß-hydroxyisobutyryl-CoA hydrolase. J. Biol. Chem. 276, 31037-31046.
Zolman, B.K., Yoder, A., and Bartel, B. (2000) Genetic analysis of indole-3-butyric acid responses in Arabidopsis thaliana reveals four mutant classes. Genetics 156, 1323-1337.
Teaching InterestsPlant Molecular Biology (B4642/6642) – offered Fall 2007
Molecular Cell Biology (B4622/6622) – offered Fall 2008
Cell Biology (B3622)