Previous work showed that crossing-over in the middle of the chromosome of phage lambda requires more DNA replication than does crossing-over near the termini. Relocation of cos, the sequence that determines the lambda termini, alters the requirements for replication in a given marked interval, demonstrating that distance from cos determines the amount of DNA replication that is required for ge...

Recombineering, which is the use of homologous recombination for DNA engineering in Escherichia coli, usually uses antibiotic selection to identify the intended recombinant. When combined in a second step with counterselection using a small molecule toxin, seamless products can be obtained. Here, we report the advantages of a genetic strategy using CcdB as the counterselectable agent. Expressio...

Homologous recombination is very efficient in many organisms. For example, short PCR products have been used extensively to generate gene replacements in the yeast Saccharomyces cerevisiae (reviewed in [Que and Winzeler 2002; http://www.openbiosystems.com/productPage.php?pageType=yeast.knockout&q=0]). Very short regions of homology (from 25 to 50 bp) are sufficient for efficient recombination i...

Neural circuit mapping and manipulation are facilitated by independent control of gene expression in pre- and post-synaptic neurons. The GAL4/UAS and Q binary transcription systems have the potential to provide this capability. Of particular use in neural circuit mapping would be GAL4 and QF drivers specific for neurotransmitters and neurotransmitter receptors. Recently available Drosophila gen...

Recombineering provides the ability to make rapid, precise, and inexpensive genetic alterations to any DNA sequence, either in the chromosome or cloned onto a vector that replicates in E. coli (or other recombineering-proficient bacteria), and to do so in a highly efficient manner. Complicated genetic constructs that are impossible to make with in vitro genetic engineering can be created in day...

We report here the formation of plasmid linear multimers promoted by the Red-system of phage lambda using a multicopy plasmid comprised of lambda red alpha and red beta genes, under the control of the lambda cI857 repressor. Our observations have revealed that the multimerization of plasmid DNA is dependent on the red beta and recA genes, suggesting a concerted role for these functions in the f...

The bacterial chromosome and plasmids can be engineered in vivo by homologous recombination using PCR products and synthetic oligonucleotides as substrates. This is possible because bacteriophage-encoded recombination functions efficiently to recombine sequences with homologies as short as 35 to 40 bases. This recombineering allows DNA sequences to be inserted or deleted without regard to locat...

Rod absorbance spectra, characterized by the wavelength of peak absorbance (lambda(max)) were related to the rod opsin sequences of individual sand gobies (Pomatoschistus minutus) from four allopatric populations [Adriatic Sea (A), English Channel (E), Swedish West Coast (S) and Baltic Sea (B)]. Rod lambda(max) differed between populations in a manner correlated with differences in the spectral...

Escherichia coli strains bearing plasmids expressing phage P22 anti-RecBCD functions abc1 and abc2 were tested for the presence of recBC-like phenotypes. Abc2 induces moderate sensitivity to UV light in wild-type and recD mutant strains but severely sensitizes both recF and recJ mutants. Abc1 has little effect on UV sensitivity in wild-type or recF or recJ mutant hosts but increases the sensiti...