ITS sequences and mitochondrial DNA polymorphism in Pisolithus isolates
ITS sequences and mitochondrial DNA polymorphism in Pisolithus isolates
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Pisolithus 分离物的 ITS 序列和线粒体 DNA 多态性
DOI：
10.1017/s0953756200002586
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
E. F. Araújo
中科院分区：
文献类型：
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作者：
E. Gomes;L. D. Abreu;A. C. Borges;E. F. Araújo
利用rDNA基因ITS的核苷酸序列和线粒体DNA （mtDNA）的限制性内切多态性，对巴西、美国和法国采集的外生菌根真菌Pisolithus属分离株的遗传变异进行了研究。ITS序列比对结果显示，巴西分离株的同源性为97.0%，美国和法国分离株的同源性为97.8%，巴西和美国/法国分离株的同源性为75.7-78.5%。这些序列与文献中描述的澳大利亚、巴西和肯尼亚Pisolithus分离株的ITS序列一致。所有Pisolithus分离株的序列数据生成的共识树显示，分离株中存在许多种。mtDNA分析采用不同酶（Dra I、EcoR I、EcoR V、ha I- xba I、Hind III和Rsa I）进行总DNA限制性内切分析，并用荧光素d-UTP标记的纯化mtDNA探针进行检测。分离株Pt 90A、Pt 185R和PF与EcoR I切割的线粒体基因组的大小估计约为。分别为40.5、47.2和47.6 kb。基于mtDNA限制性内切片段的聚类分析将分离物分为两个不同的类群，这与它们的宿主特异性和地理来源一致。对12株Pisolithus分离株的线粒体rDNA （mt rDNA）进行PCR-RFLP分析，未发现多态性。这些数据证实了我们实验室之前用RAPD-PCR和rDNA PCR-RFLP标记获得的结果，并支持了最近对一些蚤类的分类研究。
Genetic variability among isolates of the ectomycorrhizal fungus genus Pisolithus collected in Brazil, USA and France was examined, based on nucleotide sequence of ITS from rDNA genes and restriction polymorphism of the mitochondrial DNA (mtDNA). Alignment of the ITS sequences showed 97.0% homology among isolates from Brazil, 97.8% homology among isolates from USA and France and 75.7-78.5% among the isolates from Brazil and USA/France. These sequences were aligned with ITS sequences of Australian, Brazilian and Kenyan Pisolithus isolates described in the literature. A consensus tree generated by sequence data of all Pisolithus isolates showed the presence of a number of species among the isolates. The mtDNA analysis was carried out by total DNA restriction analysis with different enzymes (Dra I, EcoR I, EcoR V, Hha I-Xba I, Hind III and Rsa I) and probing with purified mtDNA labelled with fluorescein d-UTP. The size of the mitochondrial genome of isolates Pt 90A, Pt 185R and PF cleaved with EcoR I was estimated to be, approx. 40.5, 47.2 and 47.6 kb, respectively. Cluster analysis based on the mtDNA restriction fragments grouped the isolates into two distinct groups, which coincide with their host specificity and geographical origins. PCR-RFLP analysis of mitochondrial rDNA (mt rDNA) from 12 Pisolithus isolates did not show any polymorphism. These data corroborate previous results obtained in our laboratory with RAPD-PCR and rDNA PCR-RFLP markers and support recent taxonomic studies where a number of Pisolithus species were described.