摘要
采用玻璃针分离法，通过显微操作器成功地分离到大豆（ＧｌｙｃｉｎｅｍａｘＬ．）单染色体。将分离到的两条大豆染色体分别放入两个０．５ｍＬＥｐｐｅｎｄｏｒｆ管中，经Ｓａｕ３Ａ酶切，并在染色体ＤＮＡ片段两端加上Ｓａｕ３Ａ人工接头后，进行两轮ＰＣＲ扩增，得到０．３～３ｋｂ之间的ＤＮＡ片段。Ｓｏｕｔｈｅｒｎ杂交表明，这些大豆单染色体扩增片段与大豆基因组ＤＮＡ之间有同源性，从而证明两条单染色体ＤＮＡ确实已被成功地扩增了，同时表明两条不同的大豆单染色体扩增产物存在一定的差异。在常规的倒置显微镜下对小型染色体进行了显微分离，为小型单染色体ＤＮＡ的体外扩增及微克隆奠定了基础。
Glass needles were successfully used to dissect the soybean (Glycine max L.) single chromosome under the micromanipulator in this research. Two dissected soybean chromosomes were digested by Sau3A in two 0.5 mL Eppendorf tubes respectively. The two ends of chromosomal fragments were ligated with Sau3A linker adoptor. After two rounds of PCR amplification, smear DNA fragments ranged from 0.3 to 3 kb were acquired. Southern hybridization result showed the PCR products from the two single soybean chromosomes were homogeneous with the soybean genomic DNA, indicating that DNAs from the two single chromosomes have been successfully amplified. At the same time, the amplified products from the two of the distinguished single chromosome appeared somewhat different. The authors dissected the small chromosomes only by a traditional inverted microscope. Therefore,this research provides a plausible chance for amplification and microcloning of single small chromosomes.
