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Title: Activity of the mammalian DNA transposon piggyBat from Myotis lucifugus is restricted by its own transposon ends
Abstract

Members of thepiggyBacsuperfamily of DNA transposons are widely distributed in host genomes ranging from insects to mammals. The human genome has retained fivepiggyBac-derived genes as domesticated elements although they are no longer mobile. Here, we have investigated the transposition properties ofpiggyBatfromMyotis lucifugus, the only known active mammalian DNA transposon, and show that its low activity in human cells is due to subterminal inhibitory DNA sequences. Activity can be dramatically improved by their removal, suggesting the existence of a mechanism for the suppression of transposon activity. The cryo-electron microscopy structure of thepiggyBattransposase pre-synaptic complex showed an unexpected mode of DNA binding and recognition using C-terminal domains that are topologically different from those of thepiggyBactransposase. Here we show that structure-based rational re-engineering of the transposase through the removal of putative phosphorylation sites and a changed domain organization - in combination with truncated transposon ends - results in a transposition system that is at least 100-fold more active than wild-typepiggyBat.

 
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PAR ID:
10565358
Author(s) / Creator(s):
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Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Communications
Volume:
16
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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