ApoE型脂蛋白羧基端的標定、製備與純化

• Main Author: 王慧玲
• Other Authors: 黃憲斌
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/61979569019358261451

碩士 === 國立中正大學 === 分子生物研究所 === 91 === stracts Apolipoprotein E (ApoE) is a plasma apolipoprotein of 299-amino acid (Mr 34,000) that is primarily synthesized in liver. ApoE plays an important role in lipoprotein transport and cholesterol clearance. ApoE is also produced and secreted by the brain as well as implicated in neuronal regeneration. The previous study has showed that ApoE contains two structural domains, the NH2-terminal and the COOH-terminal domains. The NH2-terminal domain containing the lipoprotein receptor binding region consists of a four-helix bundle with antiparallel arrangement. The COOH-terminal domain contains the lipoprotein (lipid) binding site. The structure of the COOH-terminal domain of ApoE is unknown but is predicted to be highly amphipathic α-helices. There are three major common isoforms of ApoE in human, ApoE2, ApoE3, and ApoE4. In recent studies have revealed that ApoE interacts with senile plaque in the brains of Alzheimer disease. The frequency of ApoE4 isoform is significantly higher in the population of late-onset Alzheimer disease. ApoE has been proved that the domain interaction can influence its biochemical and metabolic properties. The purpose of this study is expression and purification a large amount of ApoE COOH-terminal domain in E.coli through non labeled or labeled-medium to investigate its structure by CD and NMR studies. The result showed that the COOH-terminal domain of ApoE can be de-aggregation in buffer containing Urea more than 2M.