The Experiments
Dr. Paul Staswick, Agronomy and Horticulture/School of Biological Sciences, University of Nebraska-Lincoln
Scott Dworak, Agronomy and Horticulture, Graduate Student, University of Nebraska-Lincoln
The approach of Dr. Paul Staswick at the University of Nebraska-Lincoln is to design and carry out experiments that test a hypothesis based on his team’s or other scientists’ previous discoveries. Careful analysis of the experimental outcomes determines if the hypothesis is supported or needs refinement. This leads to the next experiment. The approach requires patience, attention to detail and creativity.
One biotic stress plants often encounter is herbivorous insects. Successful plants have mechanisms to cope with insect invasions. A series of discoveries identified jasmonic acid as a key to defense response1. This led to the following hypothesis: A plant that can chemically modify jasmonic acid can use this hormone as a signal molecule and mount a defense against feeding insects. The key was to conduct an experiment to test this hypothesis.
This lesson will focus on one set of experiments that were conducted by Scott Dworak, a graduate student who was part of Dr. Staswick’s research team. Two short videos should be viewed with this lesson. Watch the first video now by clicking on Fragrant Signals, below.
1Staswick's publications:
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.
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.