Biology subjects

Bigot, Y.

Publications and source records attributed to Bigot, Y..

3 recordsLinked to original sources

bioRxiv2025

The piggyBac derived transposase 5 (PGBD5) can interact with human piggyBac-like elements

PGBD5 is encoded by a gene domesticated at the chordate origin from a DNA transposon of the piggyBac family. During its evolution, PGBD5s sequence has been under strong purifying selection among vertebrate genomes. This suggests PGBD5 functions in the development and physiology of chordates, as recently demonstrated in mouse and human brain development, where it was implicated in double strand DNA breaks on neurons. However, biochemical PGBD5 activities remain undefined due to lack of appropriate in vitro model systems. Furthermore, coevolution of PGBD5 with hosts has likely reshaped some of its functions, resulting in differences between vertebrate PGBD5 and the insect piggybac transposase (PB). Recent studies have found that PGBD5 can interact with two different "species" of piggyBac-like transposon element (pble). Here, we show that human PGBD5 can interact with four "species" human pbles and to promote their chromosomal integration in cells, a property it shares with insect PB. Human PGBD5 can also bind to distinct chromosomal copies of human pble in cell type-specific manner, and to genomic loci containing inverted repeats in human cells akin to those found in subterminal insect pble ends. These findings expand the scope of potential biological activities of PGBD5 and other domesticated DNA transposases.

genomics↗

bioRxiv2023

Analysis of DNA transposition by DNA transposases in human cells

This manuscript discusses the recent report "Cognate restriction of transposition by piggyBac-like proteins" in Nucleic Acids Research by Beckermann et al and related recent publications about the inability to detect DNA transposition activity of human domesticated DNA transposase PGBD5. Measuring DNA transposition activity of transposases in human cells, where these enzymes can act on endogenous genomic substrates and induce DNA damage, is complicated by these and other cellular responses. Possible reasons for the discordant findings of Beckermann et al with prior independent reports of PGBD5 DNA transposition by Helou et al and Henssen et al and specific details of experimental methods in human cells are presented. In particular, by using independent experiments that reproduce PGBD5-mediated genomic integration, we demonstrate how supraphysiologic and ectopic overexpression of PGBD5 can cause DNA damage and cell death, and artifactual loss of apparent activity in clonogenic transposition reporter assays. While PGBD5 can support apparent DNA transposition, its cellular activity predominantly involves double-strand DNA breaks, deletions and other DNA rearrangements. We discuss the implications of this phenomenon for the interpretation of experimental assays and activities of domesticated DNA transposases.

molecular biology↗

bioRxiv2017

First landscape of binding to chromosomes for a domesticated mariner transposase in the human genome: diversity of genomic targets of SETMAR isoforms in two colorectal cell lines

Setmar is a 3-exons gene coding a SET domain fused to a Hsmar1 transposase. Its different transcripts theoretically encode 8 isoforms with SET moieties differently spliced. In vitro, the largest isoform binds specifically to Hsmar1 DNA ends and with no specificity to DNA when it is associated with hPso4. In colon cell lines, we found they bind specifically to two chromosomal targets depending probably on the isoform, Hsmar1 ends and sites with no conserved motifs. We also discovered that the isoforms profile was different between cell lines and patient tissues, suggesting the isoforms encoded by this gene in healthy cells and their functions are currently not investigated.

genomics↗