title: Momilactone sensitive proteins in Arabidopsis thaliana.
abstract: The labdane-related diterpenoid, momilactone B has potent growth inhibitory activity and was demonstrated to play a particularly critical role in the allelopathy of rice (Oryza sativa L.). However, there is limited information available about the mode of action of momilactone B on the growth inhibition. The present research describes the effects of momilactone B on protein expression in the early development of Arabidopsis thaliana seedling, which was determined by two-dimensional electrophoresis and MALDI-TOFMS. Momilactone B inhibited the accumulation of subtilisin-like serine protease, amyrin synthase LUP2, β-glucosidase and malate synthase at 1 h after the momilactone application. Those proteins are involved in the metabolic turnover and the production of intermediates needed for cell structures resulting in plant growth and development. Momilactone B also inhibited the breakdown of cruciferin 2, which is essential for seed germination and seedling growth to construct cell structures. Momilactone B induced the accumulation of translationally controlled tumor protein, glutathione S-transferase and 1-cysteine peroxiredoxin 1. These proteins are involved in stress responses and increased stress tolerance. In addition, glutathione S-transferase has the activity of herbicide detoxification and 1-cysteine peroxiredoxin 1 has inhibitory activity for seed germination under unfavorable conditions. The present research suggests that momilactone B may inhibit the seedling growth by the inhibition of the metabolic turnover and the production of intermediates for cell structures. In addition, momilactone induced proteins associated with plant defense responses.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kato-Noguchi
authors.forename: Shinya
authors.initials: S
authors.lastname: Kitajima
mesh_terms: D017360:Arabidopsis / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004224:Diterpenes / Q000737:chemistry / Q000494:pharmacology*; D015180:Electrophoresis, Gel, Two-Dimensional; D007783:Lactones / Q000737:chemistry / Q000494:pharmacology*; D012275:Oryza / Q000737:chemistry*; D010675:Pheromones / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology*; D036226:Seedlings / Q000737:chemistry / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D004224:Diterpenes; D007783:Lactones; D010675:Pheromones; D010936:Plant Extracts; C477203:momilactone B