Journal Article

Decoupling of DNA excision repair and RNA transcription in translocation breaksite regions of plasmacytoma-susceptible BALB/cAnPt mice.

E J Beecham, J D Owens, J D Shaughnessy, K Huppi, V A Bohr and J F Mushinski

in Carcinogenesis

Volume 18, issue 4, pages 687-694
Published in print April 1997 | ISSN: 0143-3334
Published online April 1997 | e-ISSN: 1460-2180 | DOI: http://dx.doi.org/10.1093/carcin/18.4.687
Decoupling of DNA excision repair and RNA transcription in translocation breaksite regions of plasmacytoma-susceptible BALB/cAnPt mice.

More Like This

Show all results sharing this subject:

  • Clinical Cytogenetics and Molecular Genetics

GO

Show Summary Details

Preview

Preferential repair of pyrimidine dimers in rodent cells is thought to be directly coupled to the RNA transcription machinery. The most compelling evidence for this notion is the finding that excision repair occurs more rapidly in the template strand of DNA of transcribed genes than in the non-template strand. A thorough test of this coupling concept by careful comparison of the rate of repair to the rate of transcription of a gene and its regulatory region has not been reported. In the present study, we used nuclear run-on as a measure of transcription in the c-myc and Pvt1 genes in normal B-lymphoblasts from plasmacytoma-susceptible (BALB/cAnPt) and plasmacytoma-resistant (DBA/2N) strains of mice. Previous studies have shown that these loci, but not c-abl or Dhfr are repaired differently in mouse strains: poorly in BALB/cAnPt but efficiently in DBA/2N. The results presented here indicate that in DBA/2N cells, run-on transcription from both DNA strands can be readily detected in the regions of c-myc and Pvt1 that were efficiently repaired. Unexpectedly, however, in BALB/cAnPt lymphoblasts, transcription was equivalent to that of DBA/2N, despite a dramatic reduction in efficiency of excision repair. This finding indicates that, in BALB/cAnPt lymphoblasts, DNA repair 5' to c-myc and in Pvt1 is decoupled from the RNA transcription machinery. We postulate that this dissociation of repair and transcription represents a BALB/cAnPt-specific defect in a component of the transcription/repair complex that specifically compromises repair activity but not transcription. This defect may be responsible for the inability of normal BALB/cAnPt lymphoblasts to repair DNA sequences in the c-myc 5' flank and the Pvt1 gene, inducing gene-specific instability that predisposes these loci to genetic accidents, including chromosomal translocation, retroviral integration and other mutations.

Journal Article.  0 words. 

Subjects: Clinical Cytogenetics and Molecular Genetics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.