Application of circular dichroism observed activity and structure variation of rice calcium-dependent protein kinase 2 (CDPK2)

• Main Authors: Chen ,Yung-Hsiao, 陳勇孝
• Other Authors: Hung ,Chih-Hung
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/ahqev8

碩士 === 元培科技大學 === 醫學檢驗生物技術研究所 === 100 === For plants and protozoa, calcium plays a very important role in signal transduction from cell to cell. In plants, changes in calcium in the cytoplasm are closely related to growth and environmental adaptability. Moreover, in terms of all calcium receptors, CDPKs is the largest and the most organized calcium receptor. CDPKs may be involved in the metabolism of nitrogen and carbon, the synthesis of phospholipids, transportation of water and ion, the formation of cytoskeleton and the adaptive response to environment. To activate CDPKs, in addition to calcium, specific phosphorylation would also active CDPKs. Moreover, the signal pathway of CDPKs is the target many laboratories research on. It is hoped that the function of CDPKs in signal transduction under environmental pressure (cold, dry, high salinity) can be understood in order to understand the downstream response of CDPKs. In the paper, the gene segment of rice CDPKs (GI:587498) was extracted. Expression of CDPK2(JC) recombinant proteins in E coli was carried out while the circular dichroism (AVIV410) was used to observe the difference in the structure of activated CDPK2(JC) and non-activated CDPK2(JC). Different concentrations of urea and guanidine hydrochloride(Gu．HCl) and different temperatures were introduced to observe whether chemical substances and temperature would affect the structure of activated CDPK2(JC) and non-activated CDPK2(JC). It was found in the research that the structure of activated CDPK2(JC) was more closely bonded than that of non-activated CDPK2(JC). It may be related to the folding of the structure during activation. After activation, the structure is more stable under the changes in chemical substances and high/low temmission.perature. On the other hand, the structure of non-activated CDPK2(JC) is easily separated due to changes in chemical substances and temperature. It is believed that, from the viewpoint of the structure, the structure of the activated CDPK2(JC) is better at resisting external environmental pressure. The stability of the structure is maintained which allows it to complete the signaling