18 オオムギ糊粉層におけるジベレリソ情報伝達へのAGP関与

抄録

Gibberellin, a class of plant hormones,induces transcription and secretion of α-amylases during seed germination of crop plants. Arabinogalactan-proteins (AGPs) are plant proteoglycans that have been implicated in plant growth and development. The possible involvement of AGPs in the action of gibberellin (GA) was examined by applying β-glucosyl Yariv reagent (β-Glc)_3Y, a synthetic phenyl glycoside that interacts selectively with AGPs, to barley aleurone protoplasts. Induction of α-amylase was clearly inhibited by (β-Glc)_3Y. Transfection analysis, using an α-amylase promoter-GUS fusion gene in the protoplasts, indicated that the transcriptional activation of the α-amylase promoter was inhfbited specifically by (β-Glc)_3Y. An aleurone-specific AGP was detected by reversed-phase HPLC and supported the idea that an AGP may play an important role in aleurone-specific events.