长波紫外线诱发M13mp2噬菌体基因突变的碱基特异性

Mutational specificity of M13mp2 phage by near-ultraviolet light

目的 :分析长波紫外线 (near ultraviolet ,UVA)诱发M13mp2噬菌体lacZα基因区域突变的碱基特异性。方法 :用UVA光源照射处理M13mp2噬菌体样品 ,选择突变株 ,用dye terminator方法测定lacZα基因区域的DNA序列。结果 :UVA照射引起的突变以鸟嘌呤的颠换为主 ( 6 2 % ) ,与太阳光诱发突变类型相似 ,但与中波紫外线诱发的突变类型不同。结论

Objective: To analyse the mutational specificity of near ultraviolet light (UVA) on the lacZ α region of M13mp2 phages. Methods: M13mp2 phages were irradiated and mutants selected. The DNA sequences in lacZ α region were determined with the dye terminator method. Results: Among the mutations induced by UVA, about 62% were the transversion of guanine, similar to the mutational specificity of sunlight irradiation and different from that of ultraviolet B irradiation. Conclusion: The frequent findings of transversion of guanine in sunlight irradiated phages can be attributed to the UVA component in it.