A comparison of the effects of alkylation on the DNA of sensitive and resistant Lettre-Ehrlich cells following in vivo exposure to nitrogen mustard

Autor: Edward H. L. Chun, Robert J. Rutman, L. Yin
Rok vydání: 1973
Předmět:
Zdroj: Biochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis. 324:472-481
ISSN: 0005-2787
DOI: 10.1016/0005-2787(73)90206-2
Popis: Nitrogen mustard-sensitive and resistant Lettre-Ehrlich cells have been compared as to the effects of in vivo recovery on the DNA. It has been observed that: 1. 1. Both sensitive and resistant cells rapidly open cross-links and remove alkylated bases from their DNA, the rates being indistinguishable for the two cell strains. 2. 2. Both cell types preferentially excise N7-bis-diguaninyl alkylation products as compared to total as well as to N7-mono-guaninyl alkylations. 3. 3. Sensitive cells show a rapid and uncoordinated nicking of their DNA after alkylation and a failure to rejoin the broken ends. In contrast, resistant cells show a coordinated process of excision and repair. Our data, taken in conjunction with those of Walker I. G. and Reid, D. B. (1971) Cancer Res. 31, 510, suggest the existence of various repair deficiencies in mammalian cells, analogous to repair specific ligase and endonuclease deficiencies in microorganisms.
Databáze: OpenAIRE