Repair of DNA lesions induced by ultraviolet irradiation and aromatic amines in normal and repair-deficient human lymphoblastoid cell lines.
Repair of DNA lesions induced by ultraviolet irradiation and aromatic amines in normal and repair-deficient human lymphoblastoid cell lines.
复制标题
正常和修复缺陷的人淋巴母细胞系中紫外线照射和芳香胺诱导的 DNA 损伤的修复。
作者：
T. Stevnsner;H. Frandsen;H. Autrup
采用宿主细胞复活法，研究了正常和3种修复缺陷的人淋巴母细胞系对紫外线照射和芳香胺2-amino-1-methyl-6-phenylimidazo[4，5-b]pyridine(PhIP)和N-乙酰-2-氨基荧烯(AAF)损伤的修复能力。属于着色性干皮病互补组C(XP-C)的细胞株对所有三种损伤的去除效果低于正常细胞系，但比属于着色性干皮病互补组D组(XP-D)的细胞系更有效。属于Cockayne综合征(CS-B)互补组B的细胞株表现出宿主细胞活化减少。来自CS-B患者的成纤维细胞减少了基因特异性DNA修复，但总基因组DNA修复正常，因此我们的数据表明，HCR法可以衡量基因特异性DNA修复的能力。在几乎没有DNA修复能力的XP-D细胞系中，AAF加合物对基因表达的抑制作用比UV和PhIP加合物更强。在校正了这种抑制作用后，野生型、XP-C和CS-B细胞株以相似的效率修复了低水平的AAF和UV加合物，但修复PhIP加合物的效率较低。
A host cell reactivation (HCR) assay was employed to study the capacity of a normal and three repair-deficient human lymphoblastoid cell lines to repair DNA damage induced by UV irradiation and the aromatic amines 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and N-acetyl-2-aminofluorene (AAF) respectively. The cell line belonging to xeroderma pigmentosum complementation group C (XP-C) removed all three types of damage less efficiently than the normal cell line, but more efficiently than the cell line belonging to xeroderma pigmentosum complementation group D (XP-D). The cell line belonging to complementation group B of Cockayne's syndrome (CS-B) showed reduced host cell reactivation. Fibroblasts from CS-B patients have reduced gene-specific DNA repair, but normal total genomic DNA repair, thus our data suggest that the HCR assay measures the capacity for gene-specific DNA repair. In the XP-D cell line, which had practically no DNA repair capacity, AAF adducts had a more potent inhibitory effect on gene expression than UV and PhIP adducts. When corrected for this inhibitory effect, the wild-type, XP-C and CS-B cell lines repaired low levels of AAF and UV adducts with similar efficiencies, however, PhIP adducts were repaired less efficiently.