Poster: Plant Pathogen/Symbiont Interactions

Abs # 699: Gene encoding pathogenesis-related class 10 protein of Lithospermum erythrorhizon exhibits hypersensitive responses in the plant defense system

Presenter:	Hwang, Hyun-Ju , saebool@snu.ac.kr
Authors	Hwang, Hyun-Ju  (A)   Kim, Hoyeun  (A)   Yu, Hee-Ju  (B)   Oh, Man-Ho  (C)   Kim, Sang-Gu  (A)
Affiliations:	(A): School of Biological Sciences,Seoul National University,Seoul 151-742, Republic of Korea (B): Department of Plant Biology, UC Davis, CA (C): TS Corporation R&D Center, Incheon, Korea

We previously reported that LePR cDNA encodes PR10 protein from a cDNA library prepared from shikonin-producing cells of Lithospermum erythrorhizon. Here, we have analyzed the changes of LePR1 gene expression by the signal molecules in the plant defense response. Upon pathogen infection, bacteria (Erwinia stewartii and Pseudomonas syringae) and fungi (Aspergillus nidulans and Penicillium funiculosum) strongly induced LePR1 transcripts in directly infected leaf as well as systemic leaves. When the leaves were mechanically wounded, LePR1 gene expression was also increased after 12 h upon wounding. To evaluate the involvement with signal transduction, global signal molecules were applied in the leaves. Salicylic acid and its analogues, aspirin and BTH, definitely affected to induction of LePR1 gene. Following the H₂O₂ application, expression of LePR1 transcripts showed its concentration dependency and it was highly accumulated at 18 h after treatments. Moreover, LePR1 transcript levels were increased in response to octadecanoid pathway intermediates and treatments with ABA. Our results indicate that LePR1 gene shows very extensive and sensitive responses to pathogen as well as pathogen-related signal molecules.