摘要
哺乳动物因为缺乏Δ-12和ω-3脂肪酸脱氢酶,不能自身合成必需的多不饱和脂肪酸.目前,通过转基因技术在哺乳动物体内表达ω-3脂肪酸脱氢酶,能将长链的n-6多不饱和脂肪酸转化成n-3多不饱和脂肪酸,造成体内长链的n-6多不饱和脂肪酸含量显著减低.本研究通过自我剪切2A肽介导Δ-12和ω-3脂肪酸脱氢酶(FAT-2和FAT-1)以及人过氧化氢酶(human catalase,hCAT)在小鼠的肌肉同时表达.结果表明,转基因小鼠肌肉中长链n-3多不饱和脂肪酸含量提高2.6倍,长链n-6多不饱和脂肪酸含量没有显著变化,而n-6/n-3比例显著降低(P<0.01).同时蛋白质印迹检测到人过氧化氢酶hCAT在小鼠的肌肉组织中表达,且过氧化氢酶活性比野生型小鼠显著提高(P<0.01).
Essential polyunsaturated fatty acids can not be synthesized in mammals due to the lack of Δ-12 and ω-3 fatty acid desaturases.Expressing ω-3 fatty acid desaturases in transgenic mammals could convert long chain n-6 polyunsaturated fatty acids to n-3 polyunsaturated fatty acids,significantly reducing the level of long chain n-6 polyunsaturated fatty acids.In this study,the muscle-specific transgenic mice expressed Caenorhabditis elegans FAT-1 and FAT-2 genes,which encode ω-3 and Δ-12 fatty acid desaturases respectively and human catalase hCAT gene,based on ＂self-cleaving＂ 2A peptides,and they were generated by microinjection.Fatty acids in skeletal muscle were analyzed by gas chromatography.The level of total n-3 polyunsaturated fatty acids in transgenic mice was 2.6-fold higher than that in wild type mice,while there was no significantly difference in the level of total n-6 polyunsaturated fatty acids between transgenic and wild type mice.But the skeletal muscle tissue of transgenic mice had a dramatically reduced ratio of n-6/n-3 fatty acids（P 0.01）.In addition,the expression level of human catalase was identified by Western blot,and the catalase activity of hCAT in skeletal muscle of transgenic mice was significantly higher than that of wild type mice（P 0.01）.
出处
《生物化学与生物物理进展》
SCIE
CAS
CSCD
北大核心
2012年第2期175-180,共6页
Progress In Biochemistry and Biophysics
基金
转基因重大专项资助项目(2008ZX08006-003)~~
