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Genetics of radio-adaptive response in Saccharomyces cerevisiae

Meenakshi Dwivedi


Radio-adaptive response (RAR) is a phenomenon where cells subjected to radiation stress exhibit better tolerance to the subsequently given lethal doses of radiation. Exposure to low dose radiation finds its significance in clinical evaluation of risk assessment, radiotherapy and radiation protection. The broad objectives of the present study were to understand the effects of radiation stress dose (low dose), dose rates and the cell growth conditions on radio-adaptive response (RAR), recombinogenesis and mutagenesis; to investigate the effects of low dose exposure on cell cycle progression; to record the expression of genes associated with survival, recombinogenesis, mutagenesis and cell cycle progression. The work in this thesis is centered on the physical and physiological factor affecting RAR and the genetics of RAR in Saccharomyces cerevisiae The “Experimental Investigations†dealing with the mechanistic and genetic aspects of RAR, is divided into seven different sub-parts, highlighting the specific objectives and results. 


60Co-gamma-radiation; low dose; MRX complex; radioresistance; Radio-adaptive response

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ISSN 2347 – 8853

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