We present here a general model for integrase family site-specific recombination using the geometric relationships of the cleavable phosphodiester bonds and the disposition of the recombinase monomers (defined by their binding planes) with respect to them. The 'oscillation model' is based largely on the conformations of the recombinase-bound DNA duplexes and their dynamics within Holliday junct...

The Cre/loxP system is increasingly showing promise for investigating genes involved in neural function. Here, we demonstrate that in vivo modification of genes in the mouse brain can be accomplished in a spatial- and temporal-specific manner by targeted delivery of an adeno-associated virus (AAV) encoding a green fluorescent protein/Cre recombinase (GFP/Cre) fusion protein. By using a reporter...

DNA inversion is an important mechanism by which bacteria and bacteriophage switch reversibly between phenotypic states. In such switches, the orientation of a short DNA element is flipped by a site-specific recombinase enzyme. We propose a simple model for a DNA-inversion switch in which recombinase production is dependent on the switch state (orientational control). Our model is inspired by t...

Molecular techniques now allow the design of precise genetic modifications in the mouse. Not only can defined nucleotide changes be engineered into the genome of the mouse, but genetic switches can be designed to target expression or ablation of any gene (for which basic molecular information is available) to any tissue at any defined time. These strategies promise to contribute substantially t...

We report a transgenic line with highly penetrant cre recombinase activity in the somatotrope cells of the anterior pituitary gland. Expression of the cre transgene is under the control of the locus control region of the human growth hormone gene cluster and the rat growth hormone promoter. Cre recombinase activity was assessed with two different lacZ reporter genes that require excision of a f...

The mb1 gene encodes the Ig-alpha signaling subunit of the B cell antigen receptor and is expressed exclusively in B cells beginning at the very early pro-B cell stage in the bone marrow. We examine here the efficacy of the mb1 gene as a host locus for cre recombinase expression in B cells. We show that by integrating a humanized cre recombinase into the mb1 locus we obtain extraordinarily effi...

A transgenic mouse approach was used to examine the mechanism of principal cell-specific expression of aquaporin-2 (AQP2) within the renal collecting duct. RT-PCR and immunocytochemistry revealed that murine AQP2 was expressed in principal cells in the renal collecting duct, epithelial cells of the vas deferens, and seminiferous tubules within testis. The vas deferens expression was confirmed i...

BACKGROUND Group B streptococcal infections are the leading cause of sepsis and meningitis in newborns. A rapid and reliable method for the detection of this pathogen at the time of delivery is needed for the early treatment of neonates. Isothermal amplification techniques such as recombinase polymerase amplification have advantages relative to PCR in terms of the speed of reaction and simplici...

Site-specific recombination typically occurs only between DNA sequences that have co-evolved with a natural recombinase enzyme to optimize sequence recognition, catalytic efficiency, and regulation. Here, we show that the sequence recognition and the catalysis functions of a recombinase can be specified by unrelated protein domains. We describe chimeric recombinases with a catalytic domain from...

Tn5401 is a class II transposable element derived from the gram-positive bacterium Bacillus thuringiensis. The 4,837-bp transposon encodes a Tn3-like transposase (TnpA) and an integrase-like recombinase (TnpI) and is notable for its unusually long 53-bp terminal inverted repeats (TIRs). The tnpA and tnpI genes are transcribed from a common promoter, designated P(R), that is subject to negative ...