The complete pattern of mutagenesis arising from the repair of site-specific psoralen crosslinks: analysis by oligonucleotide hybridization.
The complete pattern of mutagenesis arising from the repair of site-specific psoralen crosslinks: analysis by oligonucleotide hybridization.
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由位点特异性补骨脂素交联修复引起的诱变的完整模式：寡核苷酸杂交分析。
DOI：
10.1093/nar/12.24.9237
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发表时间：
1984
影响因子：
14.9
通讯作者：
Cantor,CR
中科院分区：
文献类型：
--
作者：
Saffran,WA;Cantor,CR
补骨脂素交联物是通过酶促插入汞化核苷酸并与含有巯基的补骨脂素在靶部位反应而被定位在pBR322的BamHI酶切位点附近的。受损的质粒在SOS诱导的E中得到修复。结肠癌细胞。通过与靶区寡核苷酸的菌落杂交检测突变体，并测定其序列。这些突变都是碱基替换，80%的转换和20%的颠换，类似于之前通过四环素耐药性丧失而鉴定的突变。然而，通过物理方法检测到的突变位点，不受表型变化的限制，遵循比遗传鉴定的更广泛的分布。它们主要出现在补骨脂素交联点，在那里可以形成T-T和T-C链间交联物。这些突变中的大多数都是沉默的。
Psoralen crosslinks were site-specifically placed in plasmid pBR322 near the BamHI site in thetetgene by enzymatically inserting mercurated nucleotides and reacting at the target site with a sulfhydryl-containing psoralen. The damaged plasmid was repaired in SOS-inducedE. colicells. Mutants were detected by colony hybridization to oligonucleotides in the target region, and their sequences were determined. The mutations are all base substitutions, 80% transitions and 20% transversions, similar to the mutations previously identified by the loss of tetracycline resistance. However, the mutation sites detected by a physical method, unconstrained by phenotypic changes, follow a broader distribution than those identified genetically. They occur primarily at favored psoralen crosslinking sites, where T-T and T-C interstrand crosslinks can be formed. A majority of these mutations are silent.