二氢杨梅素对Bloom解旋酶结构和生物学活性的影响  

Effects of dihydromyricetin on biological properties of Bloom syndrome helicase

作　　者：刘金河[1,2] 张望明 晏文涛 许键炜 葛章文[3] LIU Jin-he;ZHANG Wang-ming;YAN Wen-tao;XU Jian-wei;GE Zhang-wen(National& Guizhou Joint Engineering Lab for Cell Engineering and Biomedicine Technique,Center for Tissue Engineering and Stem Cell Research,Guizhou Province Key Lab for Regenerative Medicine,Guizhou Medicine University,Guiyang 550004,China;Key Lab of Adult Stem Cell Translational Research,Chinese Academy of Medical Sciences,Guiyang 550004,China;Dept of Laboratory Medicine,Guizhou Provincial People′s Hospital,Guiyang 550002,China;The First Affiliated Hospital of Guizhou University of Chinese Medicine,Guiyang 550001,China)

机构地区：[1]贵州医科大学细胞工程生物医药技术国家地方联合工程实验室,组织工程与干细胞实验中心,贵州省再生医学重点实验室,贵州贵阳550004 [2]中国医学科学院成体干细胞转化研究重点实验室 [3]贵州省人民医院检验科,贵州贵阳550002 [4]贵州中医药大学第一附属医院检验科,贵州贵阳550001

出　　处：《中国药理学通报》2019年第10期1453-1460,共8页Chinese Pharmacological Bulletin

基　　金：贵州省教育厅青年科技人才成长项目(黔教合KY字[2018]177);贵州省中医药管理局中医药、民族医药科学技术研究项目(No QZYY-2016-060);中国医学科学院中央级公益性科研院所基本科研业务费专项资金(No 2017PT31042,2018PT31048)

摘　　要：目的二氢杨梅素(dihydromyricetin,DMY),是一种黄酮类化合物,具有抗炎、抗肿瘤等作用,研究DMY对Bloom解旋酶(Bloom helicase,BLM)生物学活性的影响对探索DMY的抗肿瘤机制具有重要意义。方法采用紫外光谱、圆二色谱、荧光偏振和自由磷检测等方法和技术研究DMY对BLM解旋酶的生物学活性的影响。结果圆二色谱和紫外光谱结果显示,DMY能与BLM解旋酶结合,且有1个结合位点;在0~25μmol·L^-1浓度范围内,DMY对BLM解旋酶的二级结构的干扰能力成正相关,在25~75μmol·L^-1浓度范围内则相反。荧光偏振和自由磷检测实验显示,DMY能结合在BLM解旋酶上,进而抑制BLM解旋酶的解链活性。结论DMY能够竞争性结合于BLM解旋酶的DNA结合位点上,改变BLM解旋酶的空间结构,从而抑制BLM解旋酶与DNA的结合,进而抑制BLM解旋酶的生物学活性。Aim To explore the anti-tumor mechanism of dihydromyricetin(DMY),a kind of flavonoid compound with anti-inflammatory and anti-tumor effects,via studying the effect of DMY on biological activities of Bloom helicase.Methods The effect of DMY on the biological activities of BLM helicase was studied by ultraviolet spectrum(UV),circular dichroism(CD),fluorescence polarization and free phosphorus detection.Results The results of CD and UV showed that DMY could bind to a site of the BLM helicase.In the concentration of DMY in 0~25 μmol·L^-1 range,DMY showed a positive correlation with the interference ability of BLM helicase secondary structure with the increase of concentration,while in the concentration of DMY in 25~75 μmol·L^-1 range,DMY showed a negative correlation.Fluorescence polarization and free phosphorus detection experiments showed that DMY could bind to BLM helicase,thus inhibiting the helicase activity of BLM helicase.Conclusions DMY can competitively bind to the DNA binding site of BLM helicase and change the spatial structure of BLM helicase,inhibiting the binding of BLM helicase to DNA and the biological activity of BLM helicase accordingly.

关 键 词：二氢杨梅素 Bloom解旋酶 生化活性 构象 二级结构 圆二色谱 荧光偏振 

分 类 号：R284.1[医药卫生—中药学] R342.3[医药卫生—中医学]