Effect of different conserving conditions on the extraction of total DNA from Mactra chinensis Philippi and the amplification of mitochondrion 16S rRNA gene | 不同保存条件对中国蛤蜊总DNA 提取及线粒体16S rRNA 基因扩增的影响

chinois. ［目的］初步探讨保存条件对中国蛤蜊总DNA提取及线粒体16S rRNA基因扩增的影响。［方法］设置3种温度和4个时间点的正交试验，对不同温度和不同时间保存的中国蛤蜊进行总DNA提取及检验,判断不同保存条件对线粒体16S rRNA基因PCR扩增的影响。［结果］中国蛤蜊在4、-20和-40 ℃条件下保存7 d，其DNA含量和PCR电泳条带检出率均无明显差异，说明7 d内中国蛤蜊线粒体基因的保存是完好的。20和28 d的保存结果表明，在4、-20和-40 ℃条件下保存中国蛤蜊组织样的总DNA仍可出现很亮的电泳条带，但PCR结果则显示，线粒体16S rRNA基因扩增效果不好。［结论］若要利用中国蛤蜊总DNA作为模板扩增线粒体16S rRNA基因，最好能在7 d内进行。若需保存较长时间，应将样品放置在-40 ℃或更低温度。

anglais. [Objective] The study aimed to primarily discuss the different conserving conditions on extraction of total DNA from Mactra chinensis Philippi and amplification of mitochondrion 16S rRNA gene. [Method] The orthgonal experiment with 3 kinds of temperature and 4 time points was set up to make the extraction and detection of total DNA from M. chinensis conserved at different temperature and different times and determine the effect of different conserving conditions on the PCR amplification of mitochondrion 16S rRNA Gene. [Result] When M. chinensis was conserved for 7 d at 4，-20 and -40 ℃，their DNA contents and the detectable rates of PCR electrophoresis band had no obvious difference，indicating that the mitochondrion gene of M. chinensis was well in conservation within 7 d. The conservation for 20 and 28 d showed that，when M. chinensis was conserved at 4，-20 and -40 ℃，the total DNA from the tissue samples still occurred the very bright electrophoresis bands，but their mitochondrion 16S rRNA PCR amplification effects weren’t good according to the PCR results. [Conclusion] If total DNA of M. chinensis was used as the temple to amplify the mitochondrion 16S rRNA PCR gene it should be done within 7 d and if the tissue sample needed to be conserved for longer time， the samples should be put at -40 ℃ or at more than -40℃.