Drosophila Piwi-family proteins have been implicated in transposon control. Here, we examine piwi-interacting RNAs (piRNAs) associated with each Drosophila Piwi protein and find that Piwi and Aubergine bind RNAs that are predominantly antisense to transposons, whereas Ago3 complexes contain predominantly sense piRNAs. As in mammals, the majority of Drosophila piRNAs are derived from discrete ge...

We describe a method of screening for transposon insertions in or near Drosophila loci that correspond to cloned DNA sequences. We mobilize a modified P element transposon that carries a bacterial plasmid origin of replication and a drug-resistance marker. The genomic sequences flanking each transposon insertion site can then be rescued as a plasmid in Escherichia coli. Libraries of such plasmi...

A transposon was introduced close to a poorly selectable gene. This gene could be cloned by using selection for the antibiotic resistance marker of the transposon.

An efficient transposon mutagenesis system using conjugative transposons Tn916 and Tn925::Tn917 was established for Clostridium acetobutylicum P262, an industrial strain which has proved difficult to manipulate genetically. Transposon insertions occurred at several different locations to produce a variety of mutants. An oligosporogenous mutant deficient in acetone and butanol production, and tw...

wide range of genome manipulations. Ivics and colleagues review the basics of transposon biology and of transposon use in the mouse as a vertebrate model system. The authors discuss the application of transposons to the transgenesis of somatic and germ cells, embryonic stem cells and induced pluripotent stem cells as well as their use in forward genetic screens. Readers are alerted to important...

Streptococcus agalactiae (GBS) is a major source of human perinatal diseases and bovine mastitis. Erythromycin (Ery) and tetracycline (Tet) are usually employed for preventing human and bovine infections although resistance to such agents has become common among GBS strains. Ery and Tet resistance genes are usually carried by conjugative transposons (CTns) belonging to the Tn916 family, but the...

A modified mariner transposon, miniHimar RB1, was generated to mutagenize cells of the metal-reducing bacterium Shewanella oneidensis. The use of this transposon led to the isolation of stable mutants and allowed rapid identification of disrupted genes. Fifty-eight mutants, including BG104 and BG148 with transposon insertions in the cytochrome c maturation genes ccmC and ccmF1, respectively, we...

We have developed a transposon mutagenesis system for Vibrio fischeri ES114 that utilizes a hyperactive mutant Tn5 transposase (E54K and M56A) and optimized transposon ends. Using a conjugation-based procedure, we obtained independent single-insertion mini-Tn5 mutants at a rate of approximately 10(-6). This simple and inexpensive technique represents a significant improvement over previous meth...