Ecophysiology and genetic analysis of plant adaptation to soil metal contamination

土壤中金属含量过高对植物生态系统的可持续性构成严重威胁。该研究计划旨在获得关于在生物修复中具有高潜力的关键植物物种如何科普金属污染的新的基础知识。我们的实验室首次证明了簇毛草是一种金属排斥者;山杨（颤抖的白杨），白桦（白色桦树）和红栎（红橡树）是金属排斥者，而红槭（红枫）使用回避来科普金属。我们在B中建立了镍抗性的遗传学。papyrifera、A.rubrum和A.甘蔗（银枫）。重要的是，我们已经完成并表征了B的第一个转录组。纸莎草我们已经确定了五个候选基因镍抗性从这个转录组。我们认为，最强大的替代方案，以促进更好地了解植物应对金属污染的机制是使用的方法相结合。使用遗传分析、转录组测序和RT-qPCR对五种目标植物物种进行比较分析，将允许鉴定在对过量镍和铜的响应期间差异调节的功能基因组。电子显微镜，荧光原位，和蛋白质表征技术将被用来建立细胞和细胞外分布图，以及镍和铜沿着与运输蛋白的主要影响。我们将通过使用LC-MS/MS、甲基化敏感扩增多态性（MSAP）和简化代表测序（RRS）来加深我们对DNA甲基化的理解。从我们的研究计划的信息将有助于建立重金属稳态是如何实现的图片，以及不同基因的作用，认识到可能有在不同物种的转运蛋白的操作，例如金属的转运和排斥的重大差异。挑战在于定义和操纵植物吸收、挤压和分隔金属的机制，并将其重新分配到不同的组织中。如果我们作为科学家实现了这些目标，我们不仅可以回答一些基本问题，而且还可以解决重要的生物技术应用，这些应用可以在人类营养和植物修复方面加以利用。因此，为这些应用设计或选择植物的策略无疑是非常重要的。

Excessive soil concentrations of metals represent serious threats to plant ecosystem sustainability. This research program aims to acquire new fundamental knowledge on how key plant species with high potential in bioremediation cope with metal contamination. Our lab has demonstrated for the first time that Deschampsia cespitosa (tufted hair grass) is a metal excluder; Populus tremuloides (trembling aspen), Betula papyrifera (white birch), and Quercus rubra (red oak) are accumulators, and Acer rubrum (red maple) uses avoidance to cope with metals. We have established the genetics of nickel resistance in B. papyrifera, A.rubrum, and A. saccharum (silver maple). Importantly; we have completed and characterized the first transcriptome of B. papyrifera. We have identified five candidate genes for nickel resistance from this transcriptome. We believe that the most robust alternative to facilitate a better understanding of plant coping mechanisms to metal contamination is to use a combination of approaches. Comparative analysis of five targeted plant species using genetic analysis, transcriptome sequencing and RT-qPCR will allow the identification of functional gene sets that are differentially regulated during the response to excess nickel and copper. Electron microscopy, fluorescence in situ, and protein characterization techniques will be used to establish cellular and extracellular distribution maps as well as main effects of Ni and Cu along with the transport proteins involved. We will deepen our understanding of DNA methylation by using LC- MS/MS, methylation-sensitive amplified polymorphism (MSAP), and reduced representation sequencing (RRS). The information from our research program will contribute to building a picture of how heavy metal homeostasis is achieved, and the role of different genes, recognizing that there may be major differences in the operation of transporters in different species e.g. metal accumulators and excluders. The challenge is to define and manipulate the mechanisms by which plants take up, extrude and compartmentalize metals, and also redistribute them in the different tissues. If we achieve these goals as scientists, we will not only have answered a number of fundamental questions but also can address significant biotechnological applications, which can be exploited, both in terms of human nutrition and phytoremediation. Thus strategies to engineer or select plants for such applications will undoubtedly be very important.