Witkin E M
Waksman Institute, Rutgers State University of New Jersey, Piscataway 08855-0759.
Bioessays. 1994 Jun;16(6):437-44. doi: 10.1002/bies.950160613.
'Mutation frequency decline' (MFD) was discovered about forty years ago, and described as the disappearance of a particular class of ultraviolet light-induced mutations in Escherichia coli that occurred whenever protein synthesis was briefly inhibited immediately after irradiation. Later, MFD was interpreted as an excision repair anomaly uniquely affecting nonsense suppressor mutations induced in certain tRNA genes. Never fully understood, MFD has recently been linked to the newly discovered transcription-coupled rapid repair of ultraviolet damage on the template strand of active genes. This article recalls the emergence and development of the MFD story, and offers a new way to explain it and its relation to strand-specific excision repair.
“突变频率下降”（MFD）大约在四十年前被发现，它被描述为大肠杆菌中一类特定的紫外线诱导突变的消失，这类突变在辐照后立即短暂抑制蛋白质合成时就会出现。后来，MFD被解释为一种独特的切除修复异常，它专门影响某些tRNA基因中诱导产生的无义抑制突变。由于一直未被完全理解，MFD最近被认为与新发现的活性基因模板链上紫外线损伤的转录偶联快速修复有关。本文回顾了MFD现象的出现和发展，并提供了一种新的方式来解释它以及它与链特异性切除修复的关系。
