Alcohol-derived DNA crosslinks are repaired by two distinct mechanisms

Covalent crosslinks introduced via a triple helix-forming oligonucleotide coupled to psoralen are inefficiently repaired.

Triple helix-forming oligonucleotides (TFOs) represent potentially powerful tools to artificially modulate gene activity. In particular, they can be used to specifically introduce a lesion into a selected target sequence: interstrand crosslinks and monoadducts can be introduced via TFOs coupled to psoralen. The efficiency of these strategies depends on the cell ability to repair these lesions, ...

Isolated short CTG/CAG DNA slip-outs are repaired efficiently by hMutSbeta, but clustered slip-outs are poorly repaired.

Expansions of CTG/CAG trinucleotide repeats, thought to involve slipped DNAs at the repeats, cause numerous diseases including myotonic dystrophy and Huntington's disease. By unknown mechanisms, further repeat expansions in transgenic mice carrying expanded CTG/CAG tracts require the mismatch repair (MMR) proteins MSH2 and MSH3, forming the MutSbeta complex. Using an in vitro repair assay, we i...

Processing of triplex-directed psoralen DNA interstrand crosslinks by recombination mechanisms

Gene targeting via homologous recombination (HR) is an important application in biotechnology and medicine. However, in mammalian cells HR is much less efficient than random integration. Triplex-forming oligonucleotides (TFOs) linked to DNA damaging agents (e.g. psoralen) can stimulate HR, providing the potential to improve gene therapy applications. To elucidate factors affecting TFO-directed ...

Cutting Edge: Two Distinct Mechanisms

Stress fibers are generated by two distinct actin assembly mechanisms in motile cells

Stress fibers play a central role in adhesion, motility, and morphogenesis of eukaryotic cells, but the mechanism of how these and other contractile actomyosin structures are generated is not known. By analyzing stress fiber assembly pathways using live cell microscopy, we revealed that these structures are generated by two distinct mechanisms. Dorsal stress fibers, which are connected to the s...