Twin priming: a proposed mechanism for the creation of inversions in L1 retrotransposition.

ABSTRACT: L1 retrotransposons are pervasive in the human genome. Approximately 25% of recent L1 insertions in the genome are inverted and truncated at the 5' end of the element, but the mechanism of L1 inversion has been a complete mystery. We analyzed recent L1 inversions from the genomic database and discovered several findings that suggested a mechanism for the creation of L1 inversions, which we call twin priming. Twin priming is a consequence of target primed reverse transcription (TPRT), a coupled reverse transcription/integration reaction that L1 elements are thought to use during their retrotransposition. In TPRT, the L1 endonuclease cleaves DNA at its target site to produce a double-strand break with two single-strand overhangs. During twin priming, one of the overhangs anneals to the poly(

SUBMITTER: Ostertag EM 

PROVIDER: S-EPMC311219 | biostudies-literature | 2001 Dec

REPOSITORIES: biostudies-literature