Identification of putative nonautonomous transposable elements associated with several transposon families in Caenorhabditis elegans

Putative nonautonomous transposable elements related to the autonomous transposons Tc1, Tc2, Tc5, and mariner were identified in the C. elegans database by computational analysis. These elements are found throughout the C. elegans genome and are defined by terminal inverted repeats with regions of sequence similarity, or identity, to the autonomous transposons. Similarity between loci containing related nonautonomous elements ends at, or near, the boundaries of the terminal inverted repeats. In most cases the terminal inverted repeats of the putative nonautonomous transposable elements are flanked by potential target-site duplications consistent with the associated autonomous elements. The nonautonomous elements identified vary considerably in size (from 100 bp to 1.5 kb in length) and copy number in the available database and are localized to introns and flanking regions of a wide variety of C. elegans genes.