硬软蒺藜rDNA-ITS基因序列的测定和比较

用CTAB法提取总DNA,合成位于18 S rDNA和26S rDNA上的两条各20bp的引物,通过PCR扩增ITS的全序列,对PCR产物直接测序,分别获得了硬蒺藜(Tribulus terrestris L.)和软蒺藜(Atriples centralasiatica Iljin)的核糖体RNA基因-rDNA内转录间隔区(ribosomal DNA internal transcribed spacer,rDNA-ITS)的序列643 bp和607bp,其碱基总差异率为36.16%,其中,ITS1的碱基差异率为55.81%;5.8 S的碱基差异率为6.59%;ITS2的碱基差异率为56.77%.这种差异,以及基因序列本身,为硬软蒺藜的区别和种质资源鉴定提供了分子依据.

Fingerprinting of Nucleotide Sequences of Ribosomal DNA Internal Transcribed Spacer in Tribulus terrestris L. and Atriplex centralasiatica Iljin

To distinguish YING-JI-LI(Tribulus terrestris L.) from RUAN-JI-LI(Atriplex centralasiatica Iljin) under molecular conditions,which are sometimes used unidentified in traditional Chinese medicine,the nucleotide sequences of ribosomal DNA internal transcribed spacer(rDNA-ITS) of each were achieved using polymerase chain reaction(PCR) followed by an immediate determination of sequences of PCR amplifications.643 bp nucleotides of ITS of YING-JI-LI were attained which showed a 36.16% diversity compared to 607 bp nucleotides of RUAN-JI-LI.Meanwhile,the sequences of ITS1 and ITS2 have the diversities of 55.81% and 56.77%,respectively,while 5.8 S showing 6.59%.Therefore,all of the diversities,as well as the ITS sequence itself,guarantee a DNA fingerprint for identification of YING-JI-LI and RUAN-JI-LI.