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Title: Internal initiation of reverse transcription in a Penelope-like retrotransposon
Abstract Eukaryotic retroelements are generally divided into two classes: long terminal repeat (LTR) retrotransposons and non-LTR retrotransposons. A third class of eukaryotic retroelement, the Penelope-like elements (PLEs), has been well-characterized bioinformatically, but relatively little is known about the transposition mechanism of these elements. PLEs share some features with the R2 retrotransposon fromBombyx mori, which uses a target-primed reverse transcription (TPRT) mechanism, but their distinct phylogeny suggests PLEs may utilize a novel mechanism of mobilization. Using protein purified fromE. coli, we report unique in vitro properties of a PLE from the green anole (Anolis carolinensis), revealing mechanistic aspects not shared by other retrotransposons. We found that reverse transcription is initiated at two adjacent sites within the transposon RNA that is not homologous to the cleaved DNA, a feature that is reflected in the genomic “tail” signature shared between and unique to PLEs. Our results for the first active PLE in vitro provide a starting point for understanding PLE mobilization and biology.  more » « less
Award ID(s):
2139001
PAR ID:
10557947
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
BMC / Springer Nature
Date Published:
Journal Name:
Mobile DNA
Volume:
15
Issue:
1
ISSN:
1759-8753
Subject(s) / Keyword(s):
reverse transcriptase, GIY-YIG endonuclease, hammerhead ribozyme
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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