MOLECULAR CONTROL OF FLOWER DEVELOPMENT IN ARABIDOPSIS

我实验室的研究重点是了解这些过程 控制十字花科植物拟南芥的花发育。在……里面 拟南芥中，同源异型调节基因Apetala2(AP2)的突变可以 导致萼片到心皮和花瓣的同源同源转化 雄蕊，以及花器官发育的其他戏剧性变化。 显然，Apetala2基因在决定身份方面起着核心作用 花器官原基和植物繁殖的调节。 然而，人们对该基因在分子水平上的功能一无所知。 水平。最近，我和我的同事从拟南芥中克隆了AP2基因 通过插入突变。对AP2核苷酸序列的分析 没有为该基因在细胞中的功能提供任何有意义的线索。 因此，该提案中的实验旨在生成新的 对Apetala2结构的分子和遗传学洞察 以及该基因在拟南芥发育过程中的空间调控，及其 花卉遗传控制中与其他基因座的互作 发展。首先，确定结构和/或功能上的重要 我们将比较野生型AP2基因的核苷酸序列 AP2及其侧翼DNA序列与几种化学诱变的关系 等位基因。此外，我们将确定几个有趣的主题是否 在AP2氨基酸序列中对该基因的功能至关重要，通过 利用体外定点技术产生一组新的突变等位基因 突变与这些突变基因的转化 又回到了拟南芥。我们研究的第二个目标是了解 AP2与其他参与调控的拟南芥基因座相互作用 花器官发生的。定义相互作用和/或上位性 AP2与其他已知调控基因座的关系，我们建议 观察Ap22基因表达的时空调控 利用原位杂交和免疫定位技术获得突变植株 程序。最后，为了识别与AP2相互作用的新基因 确定花器官原基的身份，我们建议筛选 同源异型表型修饰剂的诱变ap2植株--显性 Ap2的增强子和抑制子突变体。这一基因筛查应该 确定控制花卉的调控网络的其他要素 发展，包括调节器、辅助因素以及下游目标 Ap2基因。总而言之，这些研究应该为我们提供对 控制植物形态形成和繁殖的分子过程。

Research in my laboratory is focused on understanding the processes controlling flower development in the crucifer Arabidopsis thaliana. In Arabidopsis, mutations in the homeotic regulatory gene Apetala2 (Ap2) can cause the homeotic transformation of sepals to carpels and petals to stamens, as well as other dramatic changes in floral organ development. Clearly, the Apetala2 gene plays a central role in determining the identity of floral organ primordia and the regulation of plant reproduction. However, nothing is known about the function of this gene at the molecular level. Recently, my colleagues and I cloned the Ap2 gene from Arabidopsis by insertional mutagenesis. Analysis of the Ap2 nucleotide sequence has not provided any meaningful clues to this gene's function in the cell. Therefore, the experiments in this proposal are designed to generate new molecular and genetic insights into the structure of Apetala2, the temporal and spatial regulation of this gene during Arabidopsis development, and its interactions with other gene loci involved in the genetic control of flower development. First, to identify structurally and/or functionally important regions of the Ap2 gene we will compare the nucleotide sequence of wildtype Ap2 and its flanking DNA sequences with several chemically induced mutant alleles. In addition, we will determine whether several interesting motifs in the Ap2 amino acid sequence are critical for this gene's function by generating a set of new mutant alleles using in vitro site-directed mutagenesis in conjunction with the transformation of these mutant genes back into Arabidopsis. A second goal of our research is to understand how Ap2 interacts with other Arabidopsis gene loci involved in the regulation of floral organogenesis. To define the interactions and/or epistatic relationships between Ap2 and other known regulatory gene loci, we propose to look at the temporal and spatial regulation of Ap22 gene expression in mutant plants using in situ hybridization and immunolocalization procedures. Finally, to identify new genes that interact with Ap2 to determine the identity of floral organ primordia, we propose to screen mutagenized ap2 plants for modifiers of the homeotic phenotype -- dominant enhancer and suppressor mutants of ap2. This genetic screen should identify additional elements of the regulatory network controlling flower development including regulators, cofactors, as well as downstream target genes of ap2. Together, these studies should provide new insight into the molecular processes controlling plant pattern formation and reproduction.