Contemporary Transposon Tools: A Review and Guide through Mechanisms and Applications of Sleeping Beauty, piggyBac and Tol2 for Genome Engineering

Abstract

Transposons are mobile genetic elements evolved to execute highly efficient integration of their genes into the genomes of their host cells. These natural DNA transfer vehicles have been harnessed as experimental tools for stably introducing a wide variety of foreign DNA sequences, including selectable marker genes, reporters, shRNA expression cassettes, mutagenic gene trap cassettes, and therapeutic gene constructs into the genomes of target cells in a regulated and highly efficient manner. Given that transposon components are typically supplied as naked nucleic acids (DNA and RNA) or recombinant protein, their use is simple, safe, and economically competitive. Thus, transposons enable several avenues for genome manipulations in vertebrates, including transgenesis for the generation of transgenic cells in tissue culture comprising the generation of pluripotent stem cells, the production of germline-transgenic animals for basic and applied research, forward genetic screens for functional gene annotation in model species and therapy of genetic disorders in humans. This review describes the molecular mechanisms involved in transposition reactions of the three most widely used transposon systems currently available (Sleeping Beauty, piggyBac, and Tol2), and discusses the various parameters and considerations pertinent to their experimental use, highlighting the state-of-the-art in transposon technology in diverse genetic applications.

What Have We Learned in 30 Years of Investigations on Bari Transposons?

“…Initially regarded as "junk" and "useless", TEs turned out to be considered as evolutionarily flagships after reconsidering the role they have had and still have in shaping genomes and their functioning. Moreover, the characterization of many transposition systems has led to the development of efficient DNA integration tools [1] as well as powerful genome engineering systems [2,3], and to the implementation of TE control regions into efficient expression systems [4].…”

“…More in general, the so-called "cut and paste" DNA transposons are the best candidates to develop molecular tools for transgenesis because of their simple mechanism of transposition and their poor requirement of host factor [10]. Two of these elements stepped into the limelight in the past decade, the Sleeping Beauty (SB) and the piggyBac (PB) elements [1]. SB is undoubtedly the most sophisticated transposon-based system in the context of therapeutic setup.…”

The Dynamism of Transposon Methylation for Plant Development and Stress Adaptation

“…For example, Rag1 and Rag2 are TE-derived conserved genes that catalyse V(D)J somatic recombination in the vertebrate immune system [19,20]. As a consequence of the biological significance of TEs, TEs have recently been used as an integration tool in fundamental research [21] and in gene therapy [22]. TEs, or parts thereof, can also be implemented into common molecular biology tools, such as expression vectors [23].…”

Repeat Age Decomposition Informs an Ancient Set of Repeats Associated With Coleoid Cephalopod Divergence

“…Indeed, depending on the target and mode of their transposition and recombination, mobile elements can be exapted to new cis -regulatory elements ( Britten, 1996 ; Marino-Ramirez et al, 2005 ), disrupt or rewire regulatory networks ( Feschotte, 2008 ; Moschetti et al, 2020 ; Sundaram and Wysocka, 2020 ), and cause chromosomal-level rearrangements ( Gray, 2000 ). Besides, TEs are important tools for the development of new genomic integration ( Sandoval-Villegas et al, 2021 ) and expression vector technologies ( Palazzo and Marsano, 2021 ). TEs are present in every eukaryotic genome in very different proportions and classes ( Wells and Feschotte, 2020 ), with both random drift and natural selection contributing to their differential amplification in divergent lineages ( Lynch and Conery, 2003 ; Kent et al, 2017 ).…”