Genetic Program Controlling Metabolic Function of the Plant Organ

该项目旨在阐明控制植物器官新陈代谢和细胞活动的遗传程序。本项目为期4年的主要研究成果包括：(1)新的调控因子的分离；新的介导种子ABA依赖基因表达的bZIP因子(Hattori)，以及ABA诱导的参与干旱反应的MYB和MYC因子(Shinozaki)。对参与S时相特异基因表达的转录因子进行了鉴定(MESHI)。对三聚体G的基因进行了鉴定，并从水稻中分离到了三聚体G的基因干扰物岩崎。(2)突变体的分离：鉴定了糖敏感基因表达缺陷的拟南芥突变体(Nakamura)和积累蛋氨酸并影响种子贮藏蛋白的突变体(Naito)。构建了水稻转座子标签系，并对各种突变体(岛本)进行了鉴定。(3)细胞器动力学：分离了参与细胞程序性死亡的空泡处理酶基因(Nishimura)、质子泵和水通道基因(Maeshima)和参与囊泡运输的小G蛋白基因(Sasaki)，并对它们在器官发育过程中的表达模式进行了研究。线粒体tRNAs的输入冗余(Ohyama)和水稻根中皮层细胞的死亡(Uchiiya)被表征。

This project aimed to clarify genetic program controling the metabolic and cellular activities in plant organs. The major research achievements in the 4-year project include ; (1) Isolation of new regulatory factors ; New bZIP factor which mediates ABA-dependent gene expression in seeds (Hattori), and ABA-inducible MYB and MYC factors involved in drought-response (Shinozaki), were isolated. Transcription factors involved in the S phase-specific gene expression were characterized (Meshi). Genes for trimeric G were characterized and its gene-disruptant of rice was isolated (Iwasaki). (2) Isolation of mutants ; Arabidopsis mutants with defects in sugar-responsible gene expression (Nakamura), and a mutant which accumulates methionine and affects seed storage protein (Naito) were characterized. Transposon tagging lines of rice were constructed and various mutants were characterized (Shimamoto). (3) Dynamics of organelle ; Genes for vacuolar processing enzyme involved in programmed cell death (Nishimura), proton-pump and waterchannel (Maeshima), and small G-protein involved in vesicular transport (Sasaki) were isolated and their expression patterns during organ development were characterized. Import redundancy of mitochondrial tRNAs (Ohyama), and cortical cell-death in rice roots were characterized (Uchimiya).