Kafer Etta, Chae Suhn-Kee
Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada.
Fungal Genet Biol. 2008 Sep;45(9):1227-34. doi: 10.1016/j.fgb.2008.06.008. Epub 2008 Jul 4.
uvsF201 was the first highly UV-sensitive repair-defective mutation isolated in Aspergillus nidulans. It showed epistasis only with postreplication repair mutations, but caused lethal interactions with many other repair-defective strains. Unexpectedly, closest homology of uvsF was found to the large subunit of human DNA replication factor RFC that is essential for DNA replication. Sequencing of the uvsF201 region identified changes at two close base pairs and the corresponding amino acids in the 5'-region of uvsF(RFC1). This viable mutant represents a novel and possibly important type. Additional sequencing of the uvsF region confirmed a mitochondrial ribosomal protein gene, mrpA(L16), closely adjacent, head-to-head with a 0.2kb joint promoter region. MMS-induced transcription of both the genes, but especially uvsF(RFC1), providing evidence for a function in DNA damage response.
uvsF201是在构巢曲霉中分离出的第一个高度紫外线敏感的修复缺陷型突变体。它仅与复制后修复突变体表现出上位性，但与许多其他修复缺陷型菌株产生致死性相互作用。出乎意料的是，发现uvsF与人类DNA复制因子RFC的大亚基具有最密切的同源性，而RFC对DNA复制至关重要。uvsF201区域的测序确定了uvsF（RFC1）5'区域中两个相邻碱基对以及相应氨基酸的变化。这个存活的突变体代表了一种新的且可能重要的类型。uvsF区域的进一步测序证实了一个线粒体核糖体蛋白基因mrpA（L16），它与uvsF（RFC1）紧密相邻，头对头排列，有一个0.2kb的联合启动子区域。MMS诱导了这两个基因的转录，但特别是uvsF（RFC1），这为其在DNA损伤应答中的功能提供了证据。
