REVERSE-TRANSCRIPTASE ENCODED BY A HUMAN TRANSPOSABLE ELEMENT
REVERSE-TRANSCRIPTASE ENCODED BY A HUMAN TRANSPOSABLE ELEMENT
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DOI：
10.1126/science.1722352
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发表时间：
1991-12-20
期刊：
影响因子：
56.9
通讯作者：
GABRIEL, A
中科院分区：
文献类型：
--
作者：
MATHIAS, SL;SCOTT, AF;GABRIEL, A
L1元件是高度重复的哺乳动物DNA序列，其结构表明通过逆转录转座扩散。一致的L1Clement编码一种与已知逆转录酶序列相似的蛋白质。人L1元件L1.2a的第二个开放阅读框在酿酒酵母中以针对Tyl病毒样颗粒的融合蛋白的形式表达，并证明具有逆转录酶活性。这种活性被高度保守的氨基酸基序Y/F-X-D-D的错义突变所消除。因此，L1代表了逆转录酶活性的一个潜在来源，这是分散多种哺乳动物逆转录元件所必需的。
L1 elements are highly repeated mammalian DNA sequences whose structure suggests dispersal by retrotransposition. A consensus L1 clement encodes a protein with sequence similarity to known reverse transcriptases. The second open reading frame from the human L1 element L1.2A was expressed as a fusion protein targeted to Tyl virus-like particles in Saccharomyces cerevisiae and shown to have reverse transcriptase activity. This activity was eliminated by a missense mutation in the highly conserved amino acid motif Y/F-X-D-D. Thus, L1 represents a potential source of the reverse transcriptase activity necessary for dispersion of the many classes of mammalian retroelements.