The effects of UV solar light radiation on live cells using yeast (Saccharomyces cerevisiae) as a model of eukaryotes
Jobran Mohammed moshi
Genetic Department
Jazan University
Saudia Arabia
Abstract:
In this study, using yeast to define the effects of solar UV radiation, observed that when yeast cells are exposed to sunlight; all, some, or none of them may be killed. The serial dilution method used to refine the, procedure which measures the fraction of the irradiated cells that survive. With the surviving fraction data and a standard -survival curve might be defined the correlation between the exposure time of UV in sunlight and killed cells. This is a bioassay for solar UV is a guide to DNA-damaging because it is based directly on UV damage to yeast DNA. The results showed that the killer cells based on exposure period to sunlight within afternoon and sunset. The death cell in first dilution was ~20%, 94% and 95% at 30, 40, and 50min, respectively. In the third dilution the death cell percentage was ~ 9%, 52%m and 78% at 30, 40, and 50min, respectively. In the fifth dilution was ~33%, 67%, and 87% at 30, 40, and 50min, respectively. The minimum dilution (third) was less of death cells comparing the other dilutions either within 30, 40, and 50 min. It is may cells are able to repair in this dilution. The cells were not able to repair in high dilution, therefore, the death cells returned to increasing with high dilution. Protein extraction from each; control group and dilutions with exposure times were reflected the changes in genetic material (DNA). The disruptions to protein structure and regulation are displayed on gel electrophoresis.
The proteins were extracted from the exposed cells for 50 min at third dilution. The some bands which were hidden on gel, can used as primary evidence for any changes at DNA either damage or mutation. This result was obtained for cells that are able to carry out nucleotide excision repair (NER) and for cells deficient in NER. The results concluded that effects of solar UV might be depends on exposure times and time exposure of light day on the living cells.
