Figure 1.

Sleeping Beauty (SB) transposons can be designed to randomly induce somatic cell gain and loss of function mutations. (A) Structure of a proto-typical transposon vector for somatic cell or cell line mutagenesis studies. A strong promoter followed by an exon with a splice donor (SD) is present to activate transcription of downstream exons. Splice acceptors (SA) and a bi-directional polyadenylation site (pA) are included to disrupt gene expression. (B) In mutagenized cells, transposons can activate endogenous proto-oncogenes or disrupt endogenous tumor suppressor genes depending on where insertion occurs and in what orientation. (C) Transposon transgenic mice are usually produced by standard pronuclear injection resulting in the generation of lines with multicopy concatomers. These are crossed to mice expressing the transposase to generate mice with somatic cell transposition.