Polymorphism of the Internal Transcribed Spacer of nrDNA in Cinnamomum Schaeffer (Lauraceae)
In this study,nuclear ribosomal DNA (nrDNA) ITS fragments of 17 Cinnamomum samples were cloned and sequenced.A total of 87 different ITS sequences were obtained.Their length polymorphism,GC content,secondary structure stability of the 5.8S region,p-distance,evolutionary pattern and phylogenetic relationships were analyzed.The ITS sequences had a high degree of polymorphism.Among the 87 ITS sequences,22 were pseudogenes and the other 65 were functional genes.The pseudogenes showed a neutral evolutional pattern and had a higher degree of polymorphism than functional genes.The incomplete concerted evolution of the ITS region and pseudogenes within the genus Cinnamomum may have also occurred in other Lauraceae plants,which could be responsible for the low sequencing success rate of the ITS region in Lauraceae plants.
国家科技期刊平台
NSTL
万方数据
维普
