Application of Pulsed Field Gel Electrophoresis to Determine γ-ray-induced Double-strand Breaks in Yeast Chromosomal Molecules

The frequency of DNA double-strand breaks (dsb) was determined in yeast cells exposed to γ-rays under anoxic conditions. Genomic DNA of treated cells was separated by pulsed field gel electrophoresis, and two different approaches for the evaluation of the gels were employed: (1) The DNA mass distribution profile obtained by electrophoresis was compared to computed profiles, and the number of DSB per unit length was then derived in terms of a fitting procedure; (2) hybridization of selected chromosomes was performed, and a comparison of the hybridization signals in treated and untreated samples was then used to derive the frequency of dsb

Silent but Not Static: Accelerated Base-Pair Substitution in Silenced Chromatin of Budding Yeasts

Subtelomeric DNA in budding yeasts, like metazoan heterochromatin, is gene poor, repetitive, transiently silenced, and highly dynamic. The rapid evolution of subtelomeric regions is commonly thought to arise from transposon activity and increased recombination between repetitive elements. However, we found evidence of an additional factor in this diversification. We observed a surprising level of nucleotide divergence in transcriptionally silenced regions in inter-species comparisons of Saccharomyces yeasts. Likewise, intra-species analysis of polymorphisms also revealed increased SNP frequencies in both intergenic and synonymous coding positions of silenced DNA. This analysis suggested that silenced DNA in Saccharomyces cerevisiae and closely related species had increased single base-pair substitution that was likely due to the effects of the silencing machinery on DNA replication or repair

Dataset for WorldView Digital Surface Models for Sít\u27 Kusá 2013-2021 Surge Cycle

These are ~2-m resolution Digital Surface Models (DSMs) generated from WorldView image stereo pairs over Sít\u27 Kusá (Turner Glacier), southeast Alaska, and are in UTM 7N projection (EPSG:32607). All files are labeled by the date of acquisition with format YYYYMMDD. The geotiffs from 2013-2019 were provided directly by the Polar Geospatial Center. The 20180122_UTM_mosaic.tif was generated from the 20180117 and 20180128 DSMs. The 2021 DSM was generated using the NASA AMES Stereo Pipeline. The standard vertical uncertainty for these DSMs is 2 meters