Targeted and Random Transposon-Assisted Single-Copy Transgene Insertion in C. elegans.

Transgenesis in model organisms is an essential tool for determining the function of protein-coding genes and non-coding regulatory regions. In Caenorhabditis elegans, injected DNA can be propagated as multicopy extra-chromosomal arrays, but transgenes in arrays are frequently mosaic, over-expressed in some tissues, and silenced in the germline. Here, we describe methods to insert single-copy transgenes into specific genomic locations (MosSCI) or random locations (miniMos) using Mos1 transposons. Single-copy insertions allow expression at endogenous levels, expression in the germline, and identification of active and repressed regions of the genome.