Functional Study of Brassinosteroid-Regulated Proteins

油菜素类固醇(BRs)是一类植物类固醇激素，在细胞扩张、细胞分裂、维管分化、种子萌发、光形态建成、抗逆性和抗病等生理发育过程中发挥重要作用。分子遗传学研究已经确定了BR信号通路的几个组成部分，BRs通过与细胞表面受体结合来调节核基因的表达。然而，我们对当前BR信号通路的了解仍然存在空白。特别是，将BR信号从质膜转导到细胞质成分的受体激酶的底物尚不清楚。尽管基因研究取得了成功，但许多基因的功能不能通过正向遗传方法来发现，这主要是由于遗传冗余。因此，需要其他方法来显著提高我们对BR信号通路的理解。因此，蛋白质组学研究已经被用来鉴定拟南芥中受BR调节的蛋白质。这项研究的目的是表征质膜定位的BR反应蛋白，这些蛋白可能介导早期的BR信号事件。对这些蛋白质的功能研究将促进我们对BR信号转导的理解，并为提高植物生产力提供分子工具。该项目的更广泛影响包括建立有效的蛋白质组学方法和培训研究生和博士后，以发展他们在研究植物信号转导的分子遗传学和蛋白质组学方法方面的研究技能。该项目还将为本科生和高中生提供参与现代生命科学研究的机会。通过当地高中和社区大学的教师，将确定来自代表性不足的少数群体的本科生和高中生。这些学生将通过暑期和学年的研究经验被灌输对科学研究的迷恋。这将对他们未来的职业选择产生积极的影响。

Brassinosteroids (BRs) are plant steroid hormones, which play important roles in a wide range of physiological and developmental processes, including cell expansion, cell division, vascular differentiation, seed germination, photomorphogenesis, stress tolerance and disease resistance. Molecular genetic studies have identified several components of the BR signaling pathway, through which BRs bind the cell surface receptors to regulate nuclear gene expression. However, there are still gaps in our knowledge of the current BR signaling pathway. In particular, the substrates of the receptor kinases that transduce the BR signal from plasma membrane to cytoplasmic components remain unknown. Despite the success of genetic studies, the function of many genes cannot be discovered by forward genetic approaches, largely due to genetic redundancy. Therefore, alternative approaches are required to significantly advance our understanding of the BR signaling pathway. Thus, proteomic studies, which use two-dimensional difference gel electrophoresis followed by mass spectrometry, have been used to identify BR-regulated proteins in Arabidopsis. The goal of this research is to characterize plasma membrane-localized BR-responsive proteins that are likely to mediate early BR signaling events. Functional studies of these proteins will advance our understanding of BR signal transduction and provide molecular tools for improving plant productivity. The broader impacts of this project include establishment of effective proteomic methods and training graduate students and postdocs to develop their research skills in molecular genetic and proteomic approaches for studying plant signal transduction. This project will also provide opportunities for undergraduate students and high school students to participate in modern life science research. Through teachers in local high schools and community colleges, undergraduate and high school students from under-represented minority groups will be identified. These students will be instilled with a fascination for scientific research through summer and academic year research experiences. This will have a positive influence on their choice of future career.