Poster: Plant Pathogen/Symbiont Interactions

Abs # 738: Cloning of BY-2 b-1,3-glucanase cDNA induced by the addition of Alternaria alternata cultured medium

Presenter:	Saito, Mikako , mikako@cc.tuat.ac.jp
Authors	Saito, Mikako  (A)   Gondo, Shinobu  (A)   Shinya, Tomonori  (A)   Moriyama, Yuko  (A)   Matsuoka, Hideaki  (A)
Affiliations:	(A): Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology

The tobacco BY-2 chitinases were induced by the addition of Alternaria alternata cultured medium. In this study, we focused on BY-2 b-1,3-glucanase, and investigated the effect of A. alternata and 12 chemical stresses on the b-1,3-glucanase induction. In tobacco BY-2 cells, a b-1,3-glucanase activity enzyme was accumulated by the addition of salicylic acid, laminarin and several chemical stresses. Especially, pathogen fungi A. alternata culture medium induced b-1,3-glucanase activity markedly. On the other hand, methyl jasmonate and abscisic acid did not induce the b-1,3-glucanase activity. The BY-2 b-1,3-glucanase activity increased after 12-24h, and reached the maximum at 60h and then decreased by the addition of A. alternata culture medium. The time course pattern of glucanase activity was different from the pattern of BY-2 chitinases. Three class of tobacco b-1,3-glucanase cDNA was isolated as glu1 (Class I), glu2 (Class II) and glu3 (Class III) and northern blot analysis was performed with these b-1,3-glucanase cDNAs as a probe. Only the glu1 was induced by the addition of A. alternata culture medium and the transcription level of glu1 mRNA was increased gradually until 48 h. RNA blot hybridization analysis revealed that glu1 mRNA levels increased after treating cells with A. alternata culture medium.