Nonfilament-forming RecA dimer catalyzes homologous joint formation.

Homologous recombination is essential to genome maintenance, and also to genome diversification. In virtually all organisms, homologous recombination depends on the RecA/Rad51-family recombinases, which catalyze ATP-dependent formation of homologous joints-critical intermediates in homologous recombination. RecA/Rad51 binds first to single-stranded (ss) DNA at a damaged site to form a spiral nucleoprotein filament, after which double-stranded (ds) DNA interacts with the filament to search for sequence homology and to form consecutive base pairs with ssDNA ('pairing').

Successful Tissue Plasminogen Activator for a Patient with Stroke After Stanford Type A Aortic Dissection Treatment.

Some stroke patients with the acute aortic dissection receiving thrombolysis treatment resulted in fatalities. Thus, the concurrent acute aortic dissection is the contraindication for the intravenous recombinant tissue-type plasminogen activator. However, the safety and the effectiveness of the intravenous recombinant tissue-type plasminogen activator therapy are not known in patients with stroke some days after acute aortic dissection treatment.

Tissue Plasminogen Activator to Treat a Stroke after Foam Sclerotherapy in a Woman with a Patent Foramen Ovale.

Although foam sclerotherapy to varicose veins is now a popular treatment because of its high efficacy and safety, some neurologic complications have recently been reported. Presently, the effectiveness and safety of intravenous recombinant tissue-type plasminogen activator therapy to stroke following foam sclerotherapy remain unclear. Here, we report the case of a 68-year-old woman whose ischemic symptoms following foam sclerotherapy were treated by intravenous recombinant tissue-type plasminogen activator.

Rad51 and RecA juxtapose dsDNA ends ready for DNA ligase-catalyzed end-joining under recombinase-suppressive conditions.

RecA-family recombinase-catalyzed ATP-dependent homologous joint formation is critical for homologous recombination, in which RecA or Rad51 binds first to single-stranded (ss)DNA and then interacts with double-stranded (ds)DNA. However, when RecA or Rad51 interacts with dsDNA before binding to ssDNA, the homologous joint-forming activity of RecA or Rad51 is quickly suppressed. We found that under these and adenosine diphosphate (ADP)-generating suppressive conditions for the recombinase activity, RecA or Rad51 at similar optimal concentrations enhances the DNA ligase-catalyzed dsDNA end-joining (DNA ligation) about 30- to 40-fold.

Sequential steps of macroautophagy and chaperone-mediated autophagy are involved in the irreversible process of posterior silk gland histolysis during metamorphosis of Bombyx mori.

To elucidate the degradation process of the posterior silk gland during metamorphosis of the silkworm ITALIC! Bombyx mori, tissues collected on the 6th day after entering the 5th instar (V6), prior to spinning (PS), during spinning (SP) and after cocoon formation (CO) were used to analyze macroautophagy, chaperone-mediated autophagy (CMA) and the adenosine triphosphate (ATP)-dependent ubiquitin proteasome. Immediately after entering metamorphosis stage PS, the levels of ATP and phosphorylated p70S6 kinase protein decreased spontaneously and continued to decline at SP, followed by a notable restoration at CO. In contrast, phosphorylated AMP-activated protein kinase α (AMPKα) showed increases at SP and CO.

Loop L1 governs the DNA-binding specificity and order for RecA-catalyzed reactions in homologous recombination and DNA repair.

In all organisms, RecA-family recombinases catalyze homologous joint formation in homologous genetic recombination, which is essential for genome stability and diversification. In homologous joint formation, ATP-bound RecA/Rad51-recombinases first bind single-stranded DNA at its primary site and then interact with double-stranded DNA at another site. The underlying reason and the regulatory mechanism for this conserved binding order remain unknown.

Functional analyses of the C-terminal half of the Saccharomyces cerevisiae Rad52 protein.

The Saccharomyces cerevisiae Rad52 protein is essential for efficient homologous recombination (HR). An important role of Rad52 in HR is the loading of Rad51 onto replication protein A-coated single-stranded DNA (ssDNA), which is referred to as the recombination mediator activity. In vitro, Rad52 displays additional activities, including self-association, DNA binding and ssDNA annealing.

Vital roles of the second DNA-binding site of Rad52 protein in yeast homologous recombination.

RecA/Rad51 proteins are essential in homologous DNA recombination and catalyze the ATP-dependent formation of D-loops from a single-stranded DNA and an internal homologous sequence in a double-stranded DNA. RecA and Rad51 require a "recombination mediator" to overcome the interference imposed by the prior binding of single-stranded binding protein/replication protein A to the single-stranded DNA. Rad52 is the prototype of recombination mediators, and the human Rad52 protein has two distinct DNA-binding sites: the first site binds to single-stranded DNA, and the second site binds to either double- or single-stranded DNA.

Heteroduplex joint formation by a stoichiometric complex of Rad51 and Rad52 of Saccharomyces cerevisiae.

Both Rad51 and Rad52 are required for homologous genetic recombination in Saccharomyces cerevisiae. Rad51 promotes heteroduplex joint formation, a general step in homologous recombination. Rad52 facilitates the binding of Rad51 to replication protein A (RPA)-coated single-stranded DNA.