Motohashi R, Ohtsubo E, Ohtsubo H
Institute of Molecular and Cellular Biosciences, University of Tokyo, Japan.
Mol Gen Genet. 1996 Feb 5;250(2):148-52. doi: 10.1007/BF02174173.
We isolated members of the retroposon family p-SINE1 in rice and found that one member contained an insertion.Aa 3-bp sequence at the insertion site within p-SINE1 appeared duplicated. The insertion sequence, 1539 bp in length, carried imperfect inverted repeats of about 13 bp at its termini which begin with 5'-CACTA---3'; these repeats are similar to those found in members of the En/Spm transposable element family. These results indicate that the insertion sequence is a transposable element belonging to the En/Spm family and is thus named Tnr3 (transposable element in rice no. 3). In fact, Tnr carried long subterminal regions containing direct and inverted repeats of short DNA sequences of 15 bp, another characteristic of the En/Spm family. The subterminal repeat sequences in Tnr3 are, however, of two kinds, although they share homology with each other. Tnr3 and its relatives were present in multiple copies in rice. considering the length of Tnr3, it cannot represent an autonomous type element, but is a non-autonomous element probably derived by deletion from an autonomous transposon.
我们从水稻中分离出反转座子家族p-SINE1的成员，发现其中一个成员含有一个插入序列。p-SINE1内插入位点处的一个3碱基对序列出现了重复。该插入序列长度为1539 bp，在其末端带有约13 bp的不完全反向重复序列，起始于5'-CACTA---3'；这些重复序列与在En/Spm转座元件家族成员中发现的重复序列相似。这些结果表明，该插入序列是一个属于En/Spm家族的转座元件，因此被命名为Tnr3（水稻中的第3个转座元件）。事实上，Tnr携带了长的亚末端区域，其中包含15 bp短DNA序列的正向和反向重复序列，这是En/Spm家族的另一个特征。然而，Tnr3中的亚末端重复序列虽然彼此具有同源性，但有两种类型。Tnr3及其相关序列在水稻中以多拷贝形式存在。考虑到Tnr3的长度，它不能代表自主型元件，而是一个可能由自主转座子缺失而来的非自主元件。
