Frank M J, Preuss D, Mack A, Kuhlmann T C, Crawford N M
Department of Biology, University of California at San Diego, La Jolla 92093-0116, USA.
Mol Gen Genet. 1998 Feb;257(4):478-84. doi: 10.1007/pl00008622.
Tag1 is an autonomous transposable element (3.3 kb in length) first identified as an insertion in the CHL1 (NRT1) gene of Arabidopsis thaliana. Tag1 has been found in the Landsberg erecta ecotype of A. thaliana but not in Columbia or WS. In this paper, 41 additional ecotypes were examined for the presence of Tag1. Using an internal Tag1 fragment as probe, we found that DNA form 19 of the 41 ecotypes strongly hybridized to Tag1. Almost all of the Tag1-containing ecotypes had only one or two copies of Tag1 per haploid genome, as determined by Southern blot analysis. The only exception, Bf-1 from Bretagny-sur-Orge, France, had four copies. Two ecotypes, Di-G and S96, gave identical Southern blot patterns to that of Landsberg erecta and were subsequently shown to contain Tag1 at the same two positions found in Landsberg erecta (loci designated as Tag1-2 and Tag1-3). Two other ecotypes, Ag-0 and Lo-1, had a Tag1 element located at Tag1-2 but not at Tag1-3. The distance between these two loci was determined to be 0.37 cM. Analysis of DNA from two related species, A. griffithiana and A. pumila, showed that both species contain sequences that hybridize to Tag1 and that could be amplified with an oligonucleotide specific to the terminal inverted repeats of Tag1. These results show that Tag1 and related elements are present, and may be useful for insertional mutagenesis, in many A. thaliana ecotypes and several Arabidopsis species.
标签1是一种自主转座因子（长度为3.3 kb），最初被鉴定为插入拟南芥CHL1（NRT1）基因中。在拟南芥的直立型生态型中发现了标签1，但在哥伦比亚或WS生态型中未发现。在本文中，对另外41种生态型进行了标签1存在情况的检测。使用标签1内部片段作为探针，我们发现41种生态型中有19种的DNA与标签1强烈杂交。通过Southern杂交分析确定，几乎所有含有标签1的生态型每个单倍体基因组中只有一到两个标签1拷贝。唯一的例外是来自法国布雷塔尼-叙尔-奥尔热的Bf-1，有四个拷贝。两种生态型Di-G和S96的Southern杂交图谱与直立型生态型相同，随后被证明在直立型生态型中发现的相同两个位置含有标签1（位点命名为Tag1-2和Tag1-3）。另外两种生态型Ag-0和Lo-1在Tag1-2位点有一个标签1元件，但在Tag1-3位点没有。这两个位点之间的距离确定为0.37 cM。对两个近缘物种——格里菲斯拟南芥和矮小拟南芥的DNA分析表明，这两个物种都含有与标签1杂交且能用标签1末端反向重复序列特异性寡核苷酸扩增的序列。这些结果表明，标签1及相关元件存在于许多拟南芥生态型和几个拟南芥物种中，并且可能对插入诱变有用。
