Investigating the interface between plant metabolism and development

我的研究项目使用分子遗传学和生物化学工具来研究与腺嘌呤和腺苷代谢相关的酶活性，以确定它们对植物发育的贡献。这些酶被认为是“管家”活动，因为它们在所有细胞中以不同程度表达，在这些细胞中它们满足基本代谢需要;它们通常有助于多种生化途径。相应基因中的突变导致复杂的表型，这些表型通常涉及不育或致命，当敲除时，使它们成为分析的挑战。我们通过研究具有不同残留酶活性的突变体来剖析这些表型。这使我们能够确定植物代谢中每种酶活性影响的关键点以及依赖该功能的植物发育组分。我们的研究表明，这些酶履行令人惊讶的动态作用，影响发育的关键方面，并影响各种亚细胞区室：一个是“枢纽”介导的关键蛋白质-蛋白质相互作用的转甲基化反应在整个植物细胞中必不可少的，另一个控制蛋氨酸循环中产生的关键代谢产物的丰度。这种代谢物含量的变化对植物的生育力和发育有重要影响。对特定酶活性有针对性降低的突变体和基因沉默系的研究揭示了这些基本生化途径与植物激素信号传导之间的迷人串扰，其结果是关键发育事件的基础。 我使用拟南芥进行这项研究，因为它很容易维护，遗传操作和分析。由于这项研究的目标存在于所有植物中，因此结果具有广泛的相关性。目前的研究有可能提高非生物胁迫耐受性，维管发育，从而提高作物生产力。

My research program uses molecular genetic and biochemical tools to study enzyme activities associated with adenine and adenosine metabolism in order to identify their contributions to plant development. These enzymes are considered "housekeeping" activities as they are expressed in all cells to varying extents where they fulfill basic metabolic needs; they often contribute to multiple biochemical pathways. Mutations in the corresponding genes result in complex phenotypes that often involve sterility, or lethal, when knocked-out making them a challenge to analyze. We dissect these phenotypes by studying mutants that have differing residual enzyme activities. This allows us to determine the critical points in plant metabolism that each enzyme activity affects and the components of plant development that rely that function. Our research shows that these enzymes fulfill surprisingly dynamic roles impacting key aspects of development and affecting various subcellular compartments: one is a "hub" mediating critical protein-protein interactions essential for transmethylation reactions throughout plant cells, and another controls the abundance of a key metabolite produced in methionine recycling. Changes in the content of this metabolite have critical effects on plant fertility and development. The study of mutants and gene silencing lines with targeted reductions in specific enzyme activities reveals a fascinating crosstalk between these basic biochemical pathways and plant hormone signaling, the results of which underlie key developmental events. I use Arabidopsis thaliana for this research because it is easy to maintain, genetically manipulate and analyze. Because the targets of this research are present in all plants, the results have broad relevance. The current research has the potential to improve abiotic stress tolerance, vascular development and thus crop productivity.