Gardes M, Bruns T D
Department of Plant Pathology, University of California, Berkeley 94720.
Mol Ecol. 1993 Apr;2(2):113-8. doi: 10.1111/j.1365-294x.1993.tb00005.x.
We have designed two taxon-selective primers for the internal transcribed spacer (ITS) region in the nuclear ribosomal repeat unit. These primers, ITS1-F and ITS4-B, were intended to be specific to fungi and basidiomycetes, respectively. We have tested the specificity of these primers against 13 species of ascomycetes, 14 of basidiomycetes, and 15 of plants. Our results showed that ITS4-B, when paired with either a 'universal' primer ITS1 or the fungal-specific primer ITS1-F, efficiently amplified DNA from all basidiomycetes and discriminated against ascomycete DNAs. The results with plants were not as clearcut. The ITS1-F/ITS4-B primer pair produced a small amount of PCR product for certain plant species, but the quantity was in most cases less than that produced by the 'universal' ITS primers. However, under conditions where both plant and fungal DNAs were present, the fungal DNA was amplified to the apparent exclusion of plant DNA. ITS1-F/ITS4-B preferential amplification was shown to be particularly useful for detection and analysis of the basidiomycete component in ectomycorrhizae and in rust-infected tissues. These primers can be used to study the structure of ectomycorrhizal communities or the distribution of rusts on alternate hosts.
我们针对核糖体重复单元中的内转录间隔区（ITS）设计了两种分类群选择性引物。这两种引物，即ITS1-F和ITS4-B，分别旨在对真菌和担子菌具有特异性。我们针对13种子囊菌、14种担子菌和15种植物测试了这些引物的特异性。我们的结果表明，ITS4-B与“通用”引物ITS1或真菌特异性引物ITS1-F配对时，能有效扩增所有担子菌的DNA，并区分种子囊菌的DNA。植物的结果则不那么明确。ITS1-F/ITS4-B引物对能为某些植物物种产生少量PCR产物，但在大多数情况下，其产量低于“通用”ITS引物产生的产量。然而，在植物和真菌DNA都存在的条件下，真菌DNA被扩增，而植物DNA明显未被扩增。结果表明，ITS1-F/ITS4-B优先扩增对于检测和分析外生菌根及锈病感染组织中的担子菌成分特别有用。这些引物可用于研究外生菌根群落的结构或锈菌在转主寄主上的分布。
