Poster: Intracellular Signaling

Abs # 833: Characterization of phosphoproteins modified by mitogen-activated protein kinases involved in plant signal transduction

Presenter:	Kim, In-Soo , ikim@knu.ac.kr
Authors	Kim, In-Soo  (A)   Kwak, Su-Nam  (A)   Seo, Sang-Yeol  (A)
Affiliations:	(A): College of Natural Sciences, Kyung-pook National University, Daegu 702-701, Korea, South

Plant growth and development continually respond to environmental stimuli, such as light, pathogens, temperature, salinity and drought. The responses are cross-talked through signal transduction pathways so as to be properly adapted to the environment by plants. In that signal transduction, mitogen-activated protein kinases play important roles by phosphorylating down-stream signaling components. We identified several mitogen-activated protein kinases that respond to environmental stimili, cloned and expressed into soluble proteins. The proteins that were phosphorylated by the partially purified mitogen-activated protein kinases were identified by two-dimensional gel electrophoresis, chromatography and MALDI-TOF techniques. The phosphoprotein genes were also cloned from rice seedlings and expressed into soluble forms. Both the mitogen-activated protein kinases and the phosphoproteins modified by the kinases were characterized for their biochemical characteristics and their possible roles in the adaptation to environmental stimuli.