Use of a ring chromosome and pulsed-field gels to study interhomolog recombination, double-strand DNA breaks and sister-chromatid exchange in yeast.

Genetics

Division of Cellular and Molecular Biology, Lawrence Berkeley Laboratory, Berkeley, California 94720.

Published: December 1989

We describe a system that uses pulsed-field gels for the physical detection of recombinant DNA molecules, double-strand DNA breaks (DSB) and sister-chromatid exchange in the yeast Saccharomyces cerevisiae. The system makes use of a circular variant of chromosome III (Chr. III). Meiotic recombination between this ring chromosome and a linear homolog produces new molecules of sizes distinguishable on gels from either parental molecule. We demonstrate that these recombinant molecules are not present either in strains with two linear Chr. III molecules or in rad50 mutants, which are defective in meiotic recombination. In conjunction with the molecular endpoints, we present data on the timing of commitment to meiotic recombination scored genetically. We have used x-rays to linearize circular Chr. III, both to develop a sensitive method for measuring frequency of DSB and as a means of detecting double-sized circles originating in part from sister-chromatid exchange, which we find to be frequent during meiosis.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1203882PMC
http://dx.doi.org/10.1093/genetics/123.4.695DOI Listing

Publication Analysis

Top Keywords

sister-chromatid exchange
12
chr iii
12
meiotic recombination
12
ring chromosome
8
pulsed-field gels
8
double-strand dna
8
dna breaks
8
exchange yeast
8
chromosome pulsed-field
4
gels study
4

Similar Publications

Background: Carbamazepine is one of the most widely used antiepileptic drugs. Carbamazepine has been shown to be toxic to cells. Cilostazol, an antiplatelet agent, has known antioxidant, antiproliferative, anti-inflammatory, and anti-tumor effects.

View Article and Find Full Text PDF

PrimPol-mediated repriming elicits gap-filling by template switching and promotes cellular tolerance to cidofovir.

DNA Repair (Amst)

November 2024

Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo 192-0397, Japan. Electronic address:

A nucleoside analog, Cidofovir (CDV), is used for the treatment of viral diseases such as cytomegalovirus retinitis and herpes virus infection. CDV converts to its active diphosphate metabolite (CDVpp) through cellular kinases and acts as a competitive inhibitor for viral polymerase thereby interfering with viral replication. However, the effect of this drug on the replication of healthy host cells and the mechanisms involved in the cellular tolerance to CDV are yet to be fully understood.

View Article and Find Full Text PDF
Article Synopsis
  • * Research on Drosophila melanogaster revealed five causes of anaphase chromatin bridges linked to ring chromosomes, with sister chromatid catenation being the most prevalent, often resolving during anaphase through topoisomerase II action.
  • * The study also uncovered unexpected phenomena like homolog capture, where the ring chromosome connects to its linear homolog during anaphase, suggesting this may be linked to earlier mitotic pairing processes.
View Article and Find Full Text PDF

LAP2α orchestrates alternative lengthening of telomeres suppression through telomeric heterochromatin regulation with HDAC1: unveiling a potential therapeutic target.

Cell Death Dis

October 2024

The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Department of Genetics, School of Basic Medical Science, Institute of Prosthodontics School and Hospital of Stomatology, General Hospital, Tianjin Medical University, 300070, Tianjin, P. R. China.

In response to the challenge of telomere attrition during DNA replication, cancer cells predominantly employ telomerase or, in 10-15% of cases, the alternative lengthening of telomeres (ALT). The intricate details of ALT, however, remain elusive. In this study, we unveil that the knockdown of lamina-associated polypeptide 2 alpha (LAP2α) in ALT cells results in telomere dysfunction, triggering a notable increase in ALT-associated hallmarks, including high frequencies of PML bodies (APBs), C-rich extrachromosomal circles (C-circles), and telomere sister chromatid exchange (T-SCE).

View Article and Find Full Text PDF

Genome instability is a characteristic trait of tumours and includes changes in DNA and in chromosomes. The aim of the study was to identify chromosome damage using the sister chromatid exchange assay and DNA fragmentation by the comet assay in dogs with cancer, as well as to determine the suitability of these techniques for the assessment of chromatin stability in healthy and sick dogs. The assays identified genomic instabilities in dogs with cancer (squamous cell carcinoma) and in healthy dogs.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!