Blasko K, Kaplan S A, Higgins K G, Wolfson R, Sears B B
Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824.
Curr Genet. 1988 Sep;14(3):287-92. doi: 10.1007/BF00376749.
A highly variable region of chloroplast DNA has been analyzed from three isolates of Oenothera hookeri strain Johansen. The variability results from the presence of two, four or seven copies of a discrete 24-base pair tandem repeat in a segment of the chloroplast DNA within the inverted repeat. Alignment of this DNA region with the published tobacco cpDNA sequence shows that in Oenothera, the repeats are insertions within a large unidentified reading frame, with each repeat unit specifying an eight amino acid in-frame addition. A model to explain the frequent alterations in the copy number of this 24-bp unit is proposed: imprecise alignment and recombination between the two large inverted repeats followed by copy correction could result in an amplification or deletion of the 24-bp segments.
对月见草属胡克月见草约翰森菌株的三个分离株的叶绿体DNA高变区进行了分析。变异性源于在反向重复序列内的叶绿体DNA片段中存在两个、四个或七个离散的24碱基对串联重复序列。该DNA区域与已发表的烟草叶绿体DNA序列的比对表明，在月见草属中，这些重复序列是在一个大的未鉴定阅读框内的插入序列，每个重复单元指定一个框内添加的八个氨基酸。提出了一个解释该24碱基对单元拷贝数频繁变化的模型：两个大的反向重复序列之间的不精确比对和重组，随后进行拷贝校正，可能导致24碱基对片段的扩增或缺失。
