RUI: Regulation and Function of Novel CaM-Related Proteins in Arabidopsis

钙调素(CaM)蛋白的功能是将化学信号(细胞内钙的增加)转化为生化信号。在这一信号转导过程中，CaM蛋白识别并与目标蛋白功能相互作用的能力是必不可少的。在许多生物中，除了植物外，都存在一种或两种CaM类型的蛋白质。在模式生物拟南芥中，有7个已知的CaM蛋白和另外5个与CaM相关的蛋白。对拟南芥基因组的进一步分析表明，至少还有另外13种潜在的CaM相关蛋白。在这个项目中，三个CaM相关蛋白之间的生化和功能差异将被解决。这些蛋白质都含有保守的半胱氨酸残基，这些残基被认为形成了一个二硫键。这项PI将研究半胱氨酸残基和潜在的二硫键形成在钙结合和疏水树脂结合中的作用。如果二硫键的形成似乎影响了蛋白质结合钙和与疏水表面相互作用的能力，半胱氨酸残基将单独突变。突变的蛋白质将被表达和纯化，以测试特定半胱氨酸残基的消除对这些蛋白质的生化活性的影响

Calmodulin (CaM) proteins function to transduce a chemical signal (increase in cytosolic calcium) into a biochemical signal. The ability of the CaM protein to recognize and functionally interact with a target protein is essential in this signal transduction process. In many organisms, with the exception of plants, there exist one or two CaM-type proteins. In the model organism Arabidopsis thaliana there are seven known CaM proteins and five additional CaM-related proteins. Further analysis of the Arabidopsis genome suggests that there are at least an additional 13 potential CaM-related proteins. In this project, the biochemical and functional difference between three CaM-related proteins will be addressed. These proteins all possess conserved cysteine residues, which are proposed to form a disulfide bond. This PI will investigate the role of the cysteine residues and potential disulfide bond formation in calcium binding and in binding to a hydrophobic resin. If disulfide bond formation appears to influence the ability of the proteins to bind calcium and to interact with hydrophobic surfaces, the cysteine residues will be individually mutated. The mutated protein will then be expressed and purified to test the effect of elimination of specific cysteine residues on the biochemical activity of these proteins