Thellungiela halophila (Salt Cress), a Halophyte and Cryophyte Arabidopsis Relative as a Genetic Model to Identify Stress Adaptation Determinants

盐度、冰冻和渗透胁迫是植物生命和农业的主要限制因素。 自然适应的植物能够在消除所有作物和大多数其他植物物种的环境中生长;因此，这些是确定耐受性关键机制的潜在模型。 盐芥（Thellungiella halophila）是一种极端微生物，可以在NaCl浓度的海水中完成其生命周期，并能够耐受极端的冷冻温度。 盐芥提供了理想的耐盐/渗透和耐冷冻的遗传模型系统，因为它与拟南芥密切相关，并且具有遗传模型的其他属性，例如小植株尺寸、高种子产量、短生命周期和小基因组。 通过花浸渍实现了简单而有效的转化。 通过产生和筛选T-DNA插入系，通过功能丧失遗传分析从盐芥中鉴定耐盐和耐冷冻基因。 然后从插入系中筛选突变体，并通过TAIL PCR或质粒拯救方法克隆相应的耐受性基因。 该项目更广泛的影响包括功能演示如何利用拟南芥属的一个盐生植物和低温植物遗传模型系统作为遗传资源，以科普渗透、离子和冷冻胁迫的减产效应。 分子遗传资源将通过俄亥俄州州立大学的ABRC提供给整个植物生物学界。 将继续强调通过“动手”参与研究对本科生进行培训。

Project Summary Salinity, freezing and osmotic stresses are major limiting factors for plant life and agriculture. Naturally-adapted plants are able to grow in environments that eliminate all crops and most other plant species; hence, these are potential models for determining critical mechanisms of tolerance. Thellungiella halophila (salt cress) is an extremophile that can complete its life cycle in seawater concentrations of NaCl and is capable of tolerating freezing temperature extremes. Salt cress provides the ideal salt/osmotic and freezing tolerant genetic model system because it is closely related to the Arabidopsis thaliana and has other attributes of a genetic model, e.g. small plant size, high seed yield, short life cycle and a small genome. Simple and efficient transformation through floral dipping has been achieved. Salt and freezing tolerance genes will be identified from salt cress through loss-of-function genetic analyses by generating and screening T-DNA insertion lines. Mutants will then be screened from the insertion lines and the corresponding tolerance genes cloned via a TAIL PCR, or a plasmid rescue approach. The broader impact of the project includes functional demonstration of how a halophyte and cryophyte genetic model system that is a relative of Arabidopsis can be exploited as a genetic resource to cope with the yield-reducing effects of osmotic, ionic and freezing stresses. The molecular genetic resources will be made available to the entire plant biology community through the ABRC at Ohio State University. There will be continued emphasis on undergraduate student training through "hands on" participation in research.