Excision and transposition of the Tn5 element in Escherichia coli ordinarily appear to occur by recA-independent mechanisms. However, recA(Prtc) genes, which encode RecA proteins that are constitutively activated to the protease state, greatly enhanced excision and transposition; both events appeared to occur concomitantly and without destruction of the donor DNA. The recombinase function of th...

introduction patients with palliated congenital heart disease may present later in life for major, non-cardiac surgical procedures. although alternative surgical techniques are now available for the treatment of the transposition of the great arteries (tga), an atrial level baffle (mustard or senning procedure) was previously performed. long-term adverse effects of the atrial level switch inclu...

Several authors have postulated that genetic divergence between populations could result in genomic incompatibilities that would cause an increase in transposition in their hybrids, producing secondary effects such as sterility and therefore starting a speciation process. It has been demonstrated that transposition largely depends on intraspecific hybridization for P, hobo, and I elements in Dr...

We have identified and characterized the cis-acting sequences at the termini of the bacterial transposon Tn7 that are necessary for its transposition. Tn7 participates in two kinds of transposition event: high-frequency transposition to a specific target site (attTn7) and low-frequency transposition to apparently random target sites. Our analyses suggest that the same sequences at the Tn7 ends ...

A new mutagenesis assay system based on the phage 434 cI gene carried on a low-copy number plasmid was used to investigate the effect of UV light on intermolecular transposition of IS10. Inactivation of the target gene by IS10 insertion was detected by the expression of the tet gene from the phage 434 PR promoter, followed by Southern blot analysis of plasmids isolated from TetR colonies. UV ir...

The transposition frequencies of Tn10 elements from the bacterial chromosome to an F epitome decrease 40% for every kilobase increase in transposon length. The basis for this relationship is not known. We have now examined complemented transposition of defective Tn10 elements off small multicopy plasmids. We find that length dependence in this situation is either reduced or absent, depending on...

Transposable elements are often considered as selfish DNA sequences able to invade the genome of their host species. Their evolutive dynamics are complex, due to the interaction between their intrinsic amplification capacity, selection at the host level, transposition regulation, and genetic drift. Here, we propose modeling the first steps of TE invasion, i.e., just after a horizontal transfer,...

The bacterial transposon Tn7 encodes five transposition genes tnsABCDE. We report a simple and rapid procedure for the purification of TnsC protein. We show that purified TnsC is active in and required for Tn7 transposition in a cell-free recombination system. This finding demonstrates that TnsC participates directly in Tn7 transposition and explains the requirement for tnsC function in Tn7 tra...

Long ridiculed for their racial hybridity, India’s Anglo-Indians—a mixed race people—were called ‘Dingos’ and instructed rudely to “Go to Australia” after India won her Independence from the British in 1947. Although their first port of escape from India was Great Britain, thousands of Anglo-Indians left the Indian subcontinent (India, Pakistan and Sri Lanka) in the second wave of migration, i....