Baum B R, Johnson D A
Centre for Land and Biological Resources Research, Agriculture Canada, Ottawa, ON.
Genome. 1994 Dec;37(6):992-8. doi: 10.1139/g94-140.
The 5S rRNA genes from several accessions of cultivated barley, Hordeum vulgare L., were amplified by the polymerase chain reaction, cloned, and sequenced. Analysis of the aligned sequences, followed by principal coordinate analysis, support the recognition of at least two distinct classes of 5S rDNA genes. The short repeat class corresponds to the 300-bp tandem repeat defined by E.V. Ananiev as containing several TAG repeating units. The long repeat class contains long tandem repeats and lacks the TAG repeating unit. Sequences in each class can be further subdivided, with the long repeat class containing two groups and the short repeat class containing two and possibly three groups. These results suggest that in cultivated barley the sequence diversity found within the 5S rDNA nontranscribed spacer region may be encoded by three or more loci and may be useful for phylogenetic analyses provided that orthology can be established.
通过聚合酶链反应对多个栽培大麦（Hordeum vulgare L.）品种的5S rRNA基因进行扩增、克隆和测序。对排列好的序列进行分析，随后进行主坐标分析，结果支持识别出至少两类不同的5S rDNA基因。短重复类对应于E.V. 阿纳尼耶夫定义的包含几个TAG重复单元的300 bp串联重复序列。长重复类包含长串联重复序列且缺乏TAG重复单元。每类序列可进一步细分，长重复类包含两组，短重复类包含两组甚至可能三组。这些结果表明，在栽培大麦中，5S rDNA非转录间隔区发现的序列多样性可能由三个或更多位点编码，并且如果能够建立直系同源关系，可能对系统发育分析有用。
