银杏核糖体DNA内转录间隔序列初步分析

Internal transcribed spacer (ITS) sequences with Gingko biloba populations

为研究银杏Ginkgo biloba种内核糖体DNA内转录间隔(ITS)区序列的多样性,以具有代表性的10个银杏嫩叶样本为材料,提取基因组DNA后用特异性引物进行PCR扩增,并直接测定其ITS区序列。结果表明,银杏ITS区(内含5.8 S)总长度为1 224-1 226 bp,其中ITS-1长度为821-823 bp,5.8 S长度为162 bp,ITS-2长度为241 bp。在全序列范围内,可变位点有28个,占总核苷酸的2.3%,但简约信息位点仅6个,变异量仅有0.5%。银杏的不同样本之间ITS区序列表现出高度一致。

The diversity of nuclear ribosomal DNA （rDNA） internal transcribed spacer （ITS） sequences of Ginkgo biloba was determined by analyzing 10 leaf samples resenting different populations. Results showed that the total length of the ITS sequences, including 5.8 S, was 1 224 - 1 226 base pairs （bp） with ITS-1 being 821 - 823 bp long, 5.8 S having 162 bp, and ITS-2 consisting of 241 bp. Among the sequences, there were 28 variable sites, or 2.3% of the total, but only 6 parsim-informative sites, or 0.5% of the total. The ITS sequences among the different populations were very similar.