RNA made in Vitro on a DNA (from T2, T3, T4, or T7 phage) template was subjected to a limited digestion with ribonuclease T1 and fractionated according to chain length. The oligonucleotides of various chain lengths were annealed at various temperatures to denatured DNAs immobilized on membrane filters. In the absence of Mg++, a chain length of 10 or more ribonucleotides is required to form a ri...

RNA made in Vitro on a DNA (from T2, T3, T4, or T7 phage) template was subjected to a limited digestion with ribonuclease T1 and fractionated according to chain length. The oligonucleotides of various chain lengths were annealed at various temperatures to denatured DNAs immobilized on membrane filters. In the absence of Mg++, a chain length of 10 or more ribonucleotides is required to form a ri...

BACKGROUND Gene targeting depends on the ability of cells to use homologous recombination to integrate exogenous DNA into their own genome. A robust mechanistic model of homologous recombination is necessary to fully exploit gene targeting for therapeutic benefit. METHODOLOGY/PRINCIPAL FINDINGS In this work, our recently developed numerical simulation model for homology search is employed to ...

DNA flow cytometry has shown a wider spectrum of DNA content in the complete hydatidiform mole (CM) than the originally reported diploidy. Conflicting results have been published about the relationship of DNA content and the occurrence of persistent gestational trophoblastic disease (PGTD). In the present study, 71 cases of CM and 4 cases of partial mole accompanied by PGTD and 100 cases of CM ...

In human cells, large DNA loop heterologies are repaired through a nick-directed pathway independent of mismatch repair. However, a 3'-nick generated by bacteriophage fd gene II protein heterology is not capable of stimulating loop repair. To evaluate the possibility that a mismatch near a loop could induce both repair types in human cell extracts, we constructed and tested a set of DNA heterod...

DNA damage repair, loss of heterozygosity, and chromosome rearrangement are important aspects of genome stability, and all are tied to mitotic recombination. Despite the importance of mitotic recombination, the most basic questions about this process remain poorly understood. This is in part because mitotic recombination, in contrast to meiotic recombination, is rare on a per cell division basi...

Transformation is a complex process that involves several interactions from the binding and uptake of naked DNA to homologous recombination. Some actions affect transformation favourably whereas others act to limit it. Here, meticulous manipulation of a single type of transforming DNA allowed for quantifying the impact of three different mediators of meningococcal transformation: NlaIV restrict...

Plasmid heteroduplexes were constrcted that conta either 1, 4 or 5 unpaied bases within the mnt gene. These were used to assess the effciency of repai of small heterologous sequences ("heterologies ) in DNA by the Escherichia coli Dam-diected repai system. Heteroduplexes in defined states of methylation at d(G-AT-C) sites were transformed into a repai proficient indicator strain (which has a mn...

In an attempt to improve stress tolerance of tomato (Lycopersicon esculentum) plants, an expression vector containing an Arabidopsis C-repeat/dehydration responsive element binding factor 1 (CBF1) cDNA driven by a cauliflower mosaic virus 35S promoter was transferred into tomato plants. Transgenic expression of CBF1 was proved by northern- and western-blot analyses. The degree of chilling toler...