The Screening of Mutagenized abi3 Seeds of Arabidopsis thaliana for New Giberellin Sensitivity Mutants, and their Characterization

拟南芥（Arabidopsis thaliana）拟南芥（Arabidopsis thaliana）拟南芥种子诱变筛选新方法，筛选合成或响应bibberellin （GA）类植物激素能力不同的植株身高突变体。由于拟南芥通常需要GAs来抵消脱落酸（ABA）诱导的种子休眠，因此将使用AB13位点纯合隐性的种子进行原始诱变。ab13等位基因导致对ABA不敏感，从而阻止种子休眠。预计那些干扰生物合成或对GA反应的突变，以及通常会阻止种子萌发的突变，将不会损害ab13种子的萌发。因此，这种筛选方案应该允许分离新的GA突变体，特别是新的GA反应突变体。在这个奖项的12个月里，建议开始与M. Estelle博士一起对这些突变体进行遗传分析。生化分析也将开始。它将涉及使用联合气相色谱-质谱法鉴定和鉴定新的突变体中的GAs。新的GA不敏感突变体的特征，其中GA信号的接收或将该信号转导为生长反应受损，将有助于识别参与这些事件的基因。

9307067 Sponsel The proposed research involves a new screening procedure for mutagenised Arabidopsis thaliana seeds to select plant stature mutants which differ in their ability synthesize or respond to the bibberellin (GA) group of plant hormones. Since GAs are normally required to counteract abscisic acid (ABA)-induced seed dormancy in Arabidopsis the original mutagenesis will be conducted using seeds which are homozygous recessive at the AB13 locus. The ab13 allele causes insensitivity to ABA and hence prevents seed dormancy. It is expected that mutations which perturb the biosynthesis or response to GA, and which would normally prevent seed germination, will not impair germination in ab13 seeds. Therefore this screening protocol should allow the isolation of new GA mutants, especially new GA-response mutants. During the twelve months of this award it is proposed to begin the genetic analysis of these mutants in association with Dr. M. Estelle. The biochemical analysis will also be initiated. It will involved the identification and qualification of GAs in the new mutants using combined gas chromatography-mass spectrometry. The characterization of new GA-insensitive mutants in which the reception of the GA signal, or the tranduction of that signal into a growth response is impaired will assist in the identification of genes which are involved in these events.