RESEARCH INTERESTS:

My research focuses on fundamental aspects of plant biology related to plant productivity, crop plant quality and disease resistance mechanisms. Studies have included characterization of vegetative storage proteins in soybean, the hormones auxin and jasmonic acid, regulation of gene expression and soybean transformation technology.

COURSES TAUGHT:

• AGRO 810 Plant Molecular Biology (Graduate Level)

MAJOR PROJECT ACTIVITIES:

Current research involves the characterization of plant genes that regulate the activity of hormones. In the model plant arabidopsis we discovered a gene family encoding enzymes that link amino acids to the hormones auxin and jasmonic acid. These hormones are important because they help to control growth and signal resistance to diseases and pests. Surprisingly, the biochemical reaction forming the jasmonic acid-isoleucine conjugate makes jasmonic acid a more effective hormone. Other members of this enzyme family add amino acids to auxins. In contrast with jasmonic acid, this apparently converts auxin to an inactive hormone. Similar genes are found in numerous other plant species, suggesting the enzymes play an important role in plant biology. Ultimately our discoveries about how hormone activity is controlled in plants may be used to further protect plants from insects and disease or to regulate their growth.

SELECTED PUBLICATIONS:

• Melotto M, Mecey C, Niu Y, Chung HS, Katsir L, Yao J, Zeng W, Thines B, Staswick P, Browse J, Howe G, He SY (2008) The bacterial toxin coronatine and the plant hormone jasmonoyl isoleucine target the physical interaction between the Arabidopsis COI1 F-box protein and the Jas domain of JAZ repressor proteins. Plant J. (in press)

• Ueda A, Li P, Feng Y, Vikram M, Kim S, Kang CH, Kang JS, Bahk JD, Lee SY, Fukuhara T, Staswick PE, Pepper AE, Koiwa H (2008) The Arabidopsis thaliana carboxyl-terminal domain phosphatase-like 2 regulates plant growth, stress and auxin responses. Plant Mol. Biol. (in press)

• Katsir L. Schilmiller AL. Staswick PE. He SY. Howe GA. (2008) COI1 is a critical component of a receptor for jasmonate and the bacterial virulence factor coronatine. Proc. Natl. Acad. Sci. 105:7100-7105

• Staswick P. (2008) JAZing up jasmonate signaling. Trends Plant Sci. 13:66-71.

• Suza W., Staswick P. (2008) The role of JAR1 in jasmonoyl-L-isoleucine production in Arabidopsis wound response. Planta 227:1221-1232.

• Zhang Z, Li O, Li Z, Staswick PE, Wang M, Zhu Y, He Z (2007) Dual regulation role of GH3.5 in salicylic acid and auxin signaling during Arabidopsis-Pseudomonas syringae interaction. Plant Physiol. 145:450-464.

• Park JE, Park JY, Kim YS, Staswick PE, Jeon J, Yun J, Kim SY, Kim J, Lee YH, Park CM. (2007) GH3-mediated auxin homeostasis links growth regulation with stress adaptation response in Arabidopsis. J Biol Chem. 282:10036-10046.
  
  
• Guranowski A, Miersch O, Staswick PE, Suza W, Wasternack C. (2007) Substrate specificity and products of side-reactions catalyzed by jasmonate:amino acid synthetase (JAR1). FEBS Lett. 581:815-820.
  
  
• Staswick P.E., Serban B., Rowe M., Tiryaki I., Maldonado M.T., Maldonado M.C., Suza W. (2005) Characterization of an Arabidopsis Enzyme Family That Conjugates Amino Acids to Indole-3-Acetic Acid . Plant Cell 17:616-627.
  
  
• Staswick P.E. and Tiryaki I. (2004) The Oxylipin Signal Jasmonic Acid Is Activated by an Enzyme That Conjugates It to Isoleucine in Arabidopsis. Plant Cell 16:2117-2127.
  
  
• Leelapon O., Sarath G., Staswick P.E. (2004) A Single Amino Acid Substitution in Soybean VSP Increases its Acid Phosphatase Activity Nearly 20-fold . Planta 219:1071-1079.
  
  
• Tiryaki I, Staswick P.E. (2002) An Arabidopsis thaliana Mutant Defective in Jasmonate Response is Allelic to the Auxin Signaling Mutant axr1 Plant Physiol. 130: 887-894.
  
  
• Staswick P.E., Tiryaki I., Rowe M. (2002) The Jasmonate Response Locus JAR1 and Several Related Arabidopsis Genes Encode Enzymes of the Firefly Luciferase Superfamily that Show Activity on Jasmonic, Salicylic, and Indole-3-Acetic Acids in an Assay for Adenylation. Plant Cell, 14: 1405-1415.