TAD1-1, AN ACTIVE LINE-LIKE ELEMENT OF NEUROSPORA-CRASSA
TAD1-1, AN ACTIVE LINE-LIKE ELEMENT OF NEUROSPORA-CRASSA
复制标题
DOI：
10.1007/bf00283420
复制
发表时间：
1994-03-01
期刊：
影响因子：
--
通讯作者：
KINSEY, JA
中科院分区：
文献类型：
--
作者：
CAMBARERI, EB;HELBER, J;KINSEY, JA
Tad是粗糙脉孢菌的LINE样反转录转座子。该元件最初是使用am基因作为转座子陷阱在杂交菌株中检测和克隆的，所述杂交菌株源自Adiopodoume（野生收集菌株）和缺乏Tad元件的实验室菌株的杂交。我们报告的活性Tad元件，Tad 1 -1，这是能够独立转座的克隆和测序。通过筛选将该元件从含有Tad 1 -1元件作为唯一活性Tad的供体核转移到强制异核体内的幼稚核中来证明转座。我们还报告了Tad 1 -1的序列分析，并与另一个活性元件Tad 3 -2的序列进行了比较。这些元件的长度约为7 kb。它们含有两个长的开放阅读框（ORF），编码在与全长转录本相同极性的链上。ORF 1编码一个486个氨基酸的蛋白质。与其他LINE元件的第一个ORF的同源性仅限于位于羧基末端附近的三个富含半胱氨酸的基序，这些基序被认为参与结合核酸。第二个ORF长度为1156个氨基酸，与各种逆转录病毒和逆转录转座子的逆转录酶结构域具有同源性。Tad 1 -1和Tad 3 -2在其全长上仅在10个位置上不同。
Tad is a LINE-like retrotransposon of Neurospora crassa. The element was originally detected and cloned using the am gene as a transposon trap in hybrid strains derived from a cross of Adiopodoume (a wild collected strain) and a laboratory strain devoid of Tad elements. We report the cloning and sequencing of an active Tad element, Tad1-1, which is capable of independent transposition. Transposition was demonstrated by screening for transfer of the element from a donor nucleus that contained the Tad1-1 element as the only active Tad, into a naive nucleus within a forced heterokaryon. We also report here the sequence analysis of Tad1-1, and its comparison with the sequence of another active element, Tad3-2. These elements are approximately 7 kb in length. They contain two long open reading frames (ORFs) encoded on the strand of the same polarity as the full-length transcript. ORF1 encodes a putative protein of 486 amino acids. Homology to the first ORF of other LINE elements is confined to three cysteine-rich motifs, located near the carboxy-terminus, that are thought to be involved in binding nucleic acids. The second ORF is 1156 amino acids in length and shows homology to the reverse transcriptase domains of various retroviruses and retrotransposons. Tad1-1 and Tad3-2 differ in only ten positions over their whole length.