拟南芥bHLH家族转录因子DYT1在花药发育过程中调控胼胝质降解(英文)  

The Arabidopsis bHLH transcription factor DYT1 is essential for anther development by regulating callose dissolution

作　　者：宋垚[1] 李晖[1] 石其龙[1] 江华[1] 陈辉[1] 钟晓丽[1] 高菊芳[1] 崔永兰[1] 杨仲南[1] 

机构地区：[1]上海师范大学生命与环境科学学院,上海200234

出　　处：《上海师范大学学报（自然科学版）》2009年第2期174-182,共9页Journal of Shanghai Normal University(Natural Sciences)

基　　金：Natural Science Foundation of China(30530100).

摘　　要：胼胝质的合成和降解是雄配子体减数分裂过程中的一个重要特征，对后期花粉成熟有重要作用．在此研究中，分离到了一个雄性不育突变体ms157，该突变体的绒毡层分化及胼胝质降解过程出现异常，导致花粉败育．图位克隆和遗传分析表明：MS157基因与bHLH家族转录因子DYT1（At4g21330）是同一基因．因此，将ms157突变体改名为dyt1-2．反式激活作用实验揭示了DYT1的激活功能域位于基因的250～504bp之间．通过酵母双杂交实验发现DYT1蛋白在体内可以形成同源二聚体来执行其功能．RT—PCR及定量PCR分析表明胼胝质酶相关基因A6的表达在突变体背景下严重下调．因此，DYT1通过调控胼胝质的降解来影响花药发育过程．Callose formation and dissolution during and after meiotic division is a unique feature of male meiosis and is important for pollen development in plants. Here, we report the identification and characterization of a male - sterile mutant, ms157, which exhibits irregular tapetum differentiation and callose dissolution during anther development in Arabidopsis. Molecular mapping and genetic analysis indicated that MS157 is an allele of bHLH transcription factor DYT1 （At4g21330）. Thus, the mutant was renamed as dyt1-2. Our trans -activation activity assay showed the activation domain of DYT1 is located in 250bp to 504bp. Yeast two hybrid assay also suggested that two DYT1 entire proteins could form homodimers in vivo. RT - PCR and Real - Time PCR analysis indicated that callase complex related gene A6 was down - regulated in the mutant background. Hence, DYT1 plays an important role in anther development by regulating caUose dissolution.

关 键 词：拟南芥 胼胝质 绒毡层 花粉 转录因子 

分 类 号：Q344.4[生物学—遗传学]