[Molecular phylogenetic analysis of Paecilomyces hepiali and Cordyceps sinensis].
Phylogenetic relationship between Paecilomyces hepiali and Cordyceps sinensis was studied by analyzing the sequence of rDNA-ITS. The samples of C. sinensis were collected from Hualong County in Qinghai Province and Kangding County in Sichuan Province in May and June, respectively. The rDNA-ITS fragments were obtained by PCR amplification with the template genomic DNA of the fresh stroma or caterpillar body of the collected samples and the cultured mycelium of P. hepiali, with the universal fungal primers ITS1/ITS4. The amplified fragments were cloned into pMD18-T Vector and sequenced. Phylogenetic analysis was performed with these sequences and those from GenBank. The result showed that all of the 46 clones randomly chosen from the amplification of C. sinensis shared identical or almost identical rDNA-ITS regions and had over 99% identity with some rDNA-ITS sequences of Hirsutella sinensis and C. sinensis registered in GenBank, but all of them had only about 72% identity with that of P. hepiali. Two pairs of specific primers were designed based on the rDNA-ITS sequence of P. hepiali, then PCR and Nest-PCR were performed with the template genomic DNA of the stroma or caterpillar body of C. sinensis samples mentioned above. The apparent bands amplified by Nest-PCR were obtained from all of the samples, and the sequences showed 100% identity with the rDNA-ITS sequence of P. hepiali. In addition, another pair of specific primers were designed based on the rDNA-ITS sequence registered in GenBank as the marker of C. sinensis (accession no. AB067740) but the latter only shared 87.3% identity with that of H. sinensis (accession no. AJ309353). This pair of primers was used to amplify the C. sinensis samples by PCR, and the amplified sequence showed 100% identity with that of AB067740. The result indicated that H. sinensis is the main body of C. sinensis, while some other endoparasitic fungi such as P. hepiali commonly exist in the natural C. sinensis.
Yang
Jin-Ling
JL
Key Laboratory of Biosynthesis of Natural Products, Ministry of Health, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
Xiao
Wei
W
He
Hui-Xia
HX
Zhu
Hui-Xin
HX
Wang
Shu-Fang
SF
Cheng
Ke-Di
KD
Zhu
Ping
P
D001483:Base Sequence; D032661:Cordyceps / Q000145:classification / Q000235:genetics*; D004271:DNA, Fungal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D008969:Molecular Sequence Data; D010143:Paecilomyces / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer