RIG/CAA: Salinity Tolerlance Mechanisms in Ceratopteris Richardii

高羊茅是研究植物耐盐性的细胞学和遗传学基础的模式植物。植物的耐盐机制相对未知，因为几乎没有耐盐突变体存在。C-蕨类植物有几个不同的耐盐性突变体。每个耐盐突变体都有不同的单一突变基因，使植物能够在高盐水平下生长。这些耐盐突变植物的独特之处在于，它们是蕨类植物的小心形有性生殖阶段，与较大的蕨类植物身体是分开的。一个名为stl2的突变体的耐盐生理特性和正常植物的盐分反应一样得到了很好的描述。与stl2突变体不同，钙处理通过恢复钾/钠平衡来抵消正常植物中盐胁迫的影响。盐胁迫下，钙处理对突变株stl2的生长和钾钠平衡影响不大。因此，钙在stl2突变体的耐盐性中可能具有特殊的作用。这项研究的主要目标是确定盐胁迫反应，这种反应有助于耐盐性的机制，以及钙在正常植物和stl2突变体中的作用。对模式植物拟南芥盐胁迫反应的公共领域现有遗传数据的分析，将为C-蕨类植物stl2突变体的耐盐性研究提供基础。在拟南芥中，不同组织和发育阶段对盐胁迫的反应是不同的。这些反应被限制在一小群基因上，这些基因是在两个或更多组织中持续受到盐胁迫诱导的。这些基因中的一些也可能与突变蕨类植物中发现的耐盐性有关。更广泛的影响--提高粮食和纤维作物的耐盐性是农业的一个主要目标。这将允许在盐分浓度较高的边际土地或灌溉土地上增加植物的生长和商业产量。这项工作将是对拟南芥耐盐性研究的补充，也将为维管束植物耐盐性的发展提供进化证据。由于这项研究项目是在克拉克亚特兰大大学进行的，HBCU、非裔美国本科生和研究生将通过课堂体验、学生研究项目和实验室轮换，使用植物模型系统接受当前分子和基因组技术的培训。

C-Fern, Ceratopteris richardii is a model plant for determining the cellular and genetic bases for salt tolerance in plants. Salt tolerance mechanisms in plants are relatively unknown because few salt tolerant mutants exist. C-Fern has several different salt tolerant mutants. Each salt tolerance mutant has different single mutant genes that allow the plant to grow in high levels of salt. These salt tolerance mutant plants are unique in that they are the small, heart-shaped sexual reproductive phase of the ferns, which is separate from the larger fern body. The physiology of salt tolerance in a mutant named stl2 is well characterized, as is the salt response of the normal plant. Unlike the stl2 mutant, calcium treatment counteracts the effects of salt stress in the normal plant by restoring potassium/sodium balance. Calcium treatment has little effect on the growth and potassium/sodium balance of the stl2 mutant under salt stress. Therefore, calcium may have a special role in the salt tolerance of the stl2 mutant. The major goals of this research are the determination of the salt stress response, the mechanism of that response that contributes to salt tolerance, and the role of calcium in both the normal plant and the stl2 mutant. The analysis of existing genetic data in the public domain on salt stress responses in the model plant, Arabidopsis, will provide a foundation for this research on salt tolerance of the C-Fern stl2 mutant. In Arabidopsis the salt stress responses vary among different tissues and stages of development. These responses are confined to a small group of genes that are consistently induced by salt stress in two or more tissues. Some of these genes may also be responsible for the salt tolerance found in the mutant fern. Broader Impacts - Increasing the salt tolerance of food and fiber crops is a major goal for agriculture. This will permit increased growth and commercial yield of plants on marginal lands or irrigated lands where salt concentration is high. This work will complement the salt tolerance research in Arabidopsis as well as provide evolutionary evidence for the development of salt tolerance in vascular plants. Since this research project takes place at Clark Atlanta University, an HBCU, African American undergraduate and graduate students will be trained in current molecular and genomic techniques using a plant model system through classroom experiences, student research projects, and laboratory rotations.