An increased tendency of the Genome
to acquire Mutations
when various processes involved in maintaining and replicating the genome are dysfunctional.
1Department of Biological Sciences, Rensselaer Polytechnic Institute
Mutation rates in young Saccharomyces cerevisiae cells measured through fluctuation tests are used to predict mutation frequencies for mother cells of different replicative ages. Magnetic sorting and flow cytometry are then used to measure actual mutation frequencies and age of mother cells to identify any deviations from predicted mutation frequencies.
Published October 16, 2014. Keywords: Microbiology, Aging, mutations, genome instability, Saccharomyces cerevisiae, fluctuation test, magnetic sorting, mother cell, replicative aging
JoVE Immunology and Infection
1Greehey Children's Cancer Research Institute, UT Health Science Center at San Antonio, 2Department of Cellular and Structural Biology, UT Health Science Center at San Antonio, 3Department of Pathology, UT Health Science Center at San Antonio, 4Department of Microbiology, UT Health Science Center at San Antonio, 5Cancer Therapy and Research Center, UT Health Science Center at San Antonio
Here we describe an in vivo mutagenesis assay for small numbers of purified hematopoietic cells using the LacI transgenic mouse model. The LacI gene can be isolated to determine the frequency, location, and type of DNA mutants spontaneously arisen or after exposure to genotoxins.
Published February 24, 2014. Keywords: Infection, In vivo mutagenesis, hematopoietic stem/progenitor cells, LacI mouse model, DNA mutations, E. coli
1Irell & Manella Graduate School of Biological Sciences, 2Department of Molecular and Cellular Biology, City of Hope Comprehensive Cancer Center and Beckman Research Institute, 3Department of Biochemistry and Molecular Biology, University of Southern California, Norris Comprehensive Cancer Center
The HO-stimulated translocation assay monitors single-strand annealing following the creation of DNA double-strand breaks at multiple loci in diploid Saccharomyces cerevisiae. This mechanism may model genome rearrangements in somatic cells of higher eukaryotes following exposure to high doses of ionizing radiation.
Published September 23, 2011. Keywords: Genetics, translocation formation, HO-endonuclease, Genomic Southern blot, Chromosome blot, Pulsed-field gel electrophoresis, Homologous recombination, DNA double-strand breaks, Single-strand annealing
1Department of Biochemistry, University of Oxford
Exonucleases play critical roles in ensuring genome stability. Loss of WRN exonuclease function results in premature aging. Studying substrates and other requirements of the nuclease in vitro can help elucidate its role in vivo. Here we demonstrate a rapid and reproducible fluorescence-based assay to measure its nuclease activity.
Published December 23, 2013. Keywords: Biochemistry, Aging, Premature, Exonucleases, Enzyme Assays, biochemistry, WRN, exonuclease, nuclease, RecQ, progeroid disease, aging, DmWRNexo
1Department of Synthetic Biology and Bioenergy, J. Craig Venter Institute, 2Department of Microbial and Environmental Genomics, J. Craig Venter Institute, 3Donnelly Centre & Department of Molecular Genetics, University of Toronto, 4Lunenfeld Research Institute, Mt Sinai Hospital
The Green Monster method enables the rapid assembly of multiple deletions marked with a reporter gene encoding green fluorescent protein. This method is based on driving yeast strains through repeated cycles of sexual assortment of deletions and fluorescence-based enrichment of cells carrying more deletions.
Published December 15, 2012. Keywords: Microbiology, Genetics, Synthetic Biology, Environmental Genomics, Genomics, Bioengineering, Biomedical Engineering, Cellular Biology, Multi-site genomic engineering, genetic interaction, green fluorescent protein, GFP, flow cytometry, Saccharomyces cerevisiae, yeast, Green Monster
1School of Biology, Georgia Institute of Technology
This work shows how to form an RNA/DNA hybrid at the chromosomal level and reveal transfer of genetic information from RNA to genomic DNA in yeast cells.
Published November 24, 2010. Keywords: Cellular Biology, RNA-containing oligonucleotides, ribonucleotides, RNA/DNA hybrids, yeast, transformation, gene targeting, genome instability, DNA repair
1Department of Biology, Case Western Reserve University
Growing some flax varieties under nutrient stress results in genomic variation within a subset of the genome and phenotypic variation. A complex insertion at a specific site is associated with growth under various nutrient regimes and with changes in gene expression around this site.
Published January 26, 2011. Keywords: Plant Biology, Flax, genome variation, environmental stress, small RNAs, altered gene expression
1Microbiology and Immunology, Western University, 2Biochemistry, Western University, 3Surgery, Western University, 4Oncology, Western University
Here, real-time monitoring of tumor cell metabolism, combined with an in vivo chicken embryo chorio-allantoic membrane (CAM) model of metastasis, are used to evaluate novel anti-cancer targets/agents for their ability to sensitize tumor cells to DNA damaging chemotherapeutics.
Published February 6, 2015. Keywords: Medicine, chicken embryo chorio-allantoic membrane model, real-time metabolic monitoring, anti-cancer drug testing, pre-clinical development, DNA repair
1Life Science Division, Lawrence Berkeley National Laboratory
A method to process human mammary surgical discard material is described. Processed tissue, in the form of organoids, can be stored frozen indefinitely or placed in culture for long-term growth. This method enables experimental examination of normal human epithelial cell biology, and the effects of exogenous perturbations.
Published January 3, 2013. Keywords: Cancer Biology, Medicine, Anatomy, Physiology, Cellular Biology, Tissue Culture, Tissue Engineering, Oncology, Human mammary epithelial cell culture, reduction mammoplasty, mastectomy, breast cancer, tumor, cancer, matrigel, cell culture