title: Spatially sculpted laser scissors for study of DNA damage and repair.
abstract: We present a simple and efficient method for controlled linear induction of DNA damage in live cells. By passing a pulsed laser beam through a cylindrical lens prior to expansion, an elongated elliptical beam profile is created with the ability to expose controlled linear patterns while keeping the beam and the sample stationary. The length and orientation of the beam at the sample plane were reliably controlled by an adjustable aperture and rotation of the cylindrical lens, respectively. Localized immunostaining by the DNA double strand break (DSB) markers phosphorylated H2AX (gamma H2AX) and Nbs1 in the nuclei of HeLa cells exposed to the "line scissors" was shown via confocal imaging. The line scissors method proved more efficient than the scanning mirror and scanning stage methods at induction of DNA DSB damage with the added benefit of having a greater potential for high throughput applications.
authors.affiliation: University of California, Irvine, Beckman Laser Institute and Medical Clinic, 1002 Health Sciences Road East, Irvine, California 92617, USA.
authors.forename: Jared
authors.initials: J
authors.lastname: Stephens
authors.forename: Samarendra K
authors.initials: SK
authors.lastname: Mohanty
authors.forename: Suzanne
authors.initials: S
authors.lastname: Genc
authors.forename: Xiangduo
authors.initials: X
authors.lastname: Kong
authors.forename: Kyoko
authors.initials: K
authors.lastname: Yokomori
authors.forename: Michael W
authors.initials: MW
authors.lastname: Berns
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure*; D004249:DNA Damage; D004260:DNA Repair; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009690:Nucleic Acid Conformation; D052898:Optical Tweezers; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004247:DNA