Cis-preferential LINE-1 reverse transcriptase activity in ribonucleoprotein particles.

Deanna A Kulpa; John V Moran

doi:10.1038/nsmb1107

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PubMed · 16783376

Cis-preferential LINE-1 reverse transcriptase activity in ribonucleoprotein particles.

Deanna A Kulpa·John V Moran

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Abstract

LINE-1 retrotransposons (L1s) constitute approximately 17% of human DNA, and their activity continues to affect genome evolution. Retrotransposition-competent human L1s encode two proteins required for their mobility (ORF1p and ORF2p); however, biochemical activities associated with ORF2p have been difficult to detect in cells. Here, we show for the first time the colocalization of L1 RNA, ORF1p and ORF2p to a putative ribonucleoprotein retrotransposition intermediate. We further demonstrate that ORF2p preferentially uses its encoding RNA as a template for reverse transcription. Thus, our data provide the first biochemical evidence supporting the cis-preferential action of the L1 reverse transcriptase.

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Base Sequence HeLa Cells Humans Long Interspersed Nucleotide Elements Molecular Sequence Data Nucleic Acid Conformation Open Reading Frames RNA-Directed DNA Polymerase Recombinant Proteins Retroelements Reverse Transcriptase Polymerase Chain Reaction Ribonucleoproteins Transfection Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't

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Deanna A Kulpa, John V Moran. 2006-06-18. Cis-preferential LINE-1 reverse transcriptase activity in ribonucleoprotein particles.. https://doi.org/10.1038/nsmb1107

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