Weaver D C, Shpakovski G V, Caputo E, Levin H L, Boeke J D
Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Gene. 1993 Sep 6;131(1):135-9. doi: 10.1016/0378-1119(93)90682-s.
Two families of retrotransposons, Tf1 and Tf2, have been isolated from the fission yeast, Schizosaccharomyces pombe. We report here the nucleotide (nt) sequence of a Tf2 element, the only retrotransposon family known from the commonly used laboratory strains, 972 and 975, and their derivatives. The total nt sequence of Tf2 was derived from the complete sequence of the coding region and 3' long terminal repeat (LTR) of randomly cloned element Tf2-1, and from a full 5' LTR and approximately one-third of the open reading frame (ORF) of Tf2-43, a Tf2 element found in the head-to-head orientation adjacent to the Sz. pombe rpb6 gene. The two Tf2 sequences are nearly identical and both of them contain a single ORF encoding a protein with regions of sequence similar to protease, reverse transcriptase, RNase H (RH) and integrase from other retrotransposons and retroviruses. Sequence comparisons between Tf1 and Tf2 indicate an extreme divergence of the putative capsid protein-encoding regions of these two elements, as well as divergence of a segment of the LTR, but otherwise virtually identical sequence.
已经从裂殖酵母粟酒裂殖酵母中分离出了两类逆转录转座子，即Tf1和Tf2。我们在此报告一个Tf2元件的核苷酸（nt）序列，这是从常用实验室菌株972和975及其衍生物中已知的唯一逆转录转座子家族。Tf2的总nt序列来自随机克隆的元件Tf2-1的编码区和3'长末端重复序列（LTR）的完整序列，以及来自Tf2-43的完整5' LTR和大约三分之一的开放阅读框（ORF），Tf2-43是一个在与粟酒裂殖酵母rpb6基因相邻的头对头方向上发现的Tf2元件。这两个Tf2序列几乎相同，并且它们都包含一个单一的ORF，该ORF编码一种蛋白质，其序列区域与其他逆转录转座子和逆转录病毒的蛋白酶、逆转录酶、核糖核酸酶H（RH）和整合酶相似。Tf1和Tf2之间的序列比较表明，这两个元件的假定衣壳蛋白编码区域存在极大差异，以及LTR的一段区域存在差异，但在其他方面序列几乎相同。
