Detection of laser-UV microirradiation-induced DNA photolesions by immunofluorescent staining

Detection of Laser-UV Microirradiation-induced DNA Photoiesions

A low-power laser-UV microbeam of wavelength 257 nm was used for microirradiation of a small part of the nucleus of Chinese hamster cells. Following fixation in interphflse or in the subsequent metaphase indirect immunofluorescent staining was performed with antiserum to photoproducts ofDNA treated with far UV ligh t. The results show that antibodies specific for UVirradiated DNA can be used fo...

Laser-UV-microirradiation of Chinese hamster cells: the influence of the distribution of photolesions on unscheduled DNA synthesis.

Fibroblastoid Chinese hamster cells synchronized by mitotic selection were microirradiated in G1, using a low power laser-UV-microbeam (2 = 257 nm). The incident e?ergy was either concentrated on a small part of the nucleus (mode 1) or distributed over the whole nucleus (mode 11). Using the same incident UV energy, the local UV fluences were estimated to differ by two orders sf magnitude. Follo...

Detection of Legionnaires disease bacteria by direct immunofluorescent staining.

Antisera and fluorescein isothiocyanate conjugates prepared for five strains of the Legionnaires bacteria were tested in both homologous and heterologous staining reactions with 10 isolates of the organism from patients in seven geographic areas. The strains were related but not identical as judged by the results of direct immunofluorescence staining. The conjugates were successfully used to de...

Dynamics of DNA-repair factors and chromosomes studied by laser-UVA-microirradiation and laser-photobleaching

USF-1 Is Critical for Maintaining Genome Integrity in Response to UV-Induced DNA Photolesions

An important function of all organisms is to ensure that their genetic material remains intact and unaltered through generations. This is an extremely challenging task since the cell's DNA is constantly under assault by endogenous and environmental agents. To protect against this, cells have evolved effective mechanisms to recognize DNA damage, signal its presence, and mediate its repair. While...