Rds for 5 min in methanol at 220uC. Hydrogen peroxide (3 in methanol) was applied for 10 min, followed by incubation for 1 h at room temperature in 10 normal donkey serum (Chemicon, Amersfoort, The Netherlands). Phospho-Histone H2A.X (Ser139)(20E3) Rabbit monoclonal Ab (Cell Signaling, Danvers, USA; 1:200) was applied and incubated overnight at 4uC. Sections were then rinsed in PBS and incubated with rhodamine-conjugated donkey anti-rabbit secondary antibody (Santa Cruz, Santa Cruz, USA; 1:100) for 30 min at room temperature. After washing in PBS/Tween [0.2 v/v] for 5 min, the sections were counterstained with the DNA stain GW0742 bisbenzimide (AppliChem, Darmstadt, Germany; 10 mg/ml) for 3 min. Sections were washed with PBS and mounted with Confocal Matrix (Micro Tech Lab, Graz, Austria). Immunofluorescent images were captured using an Eclipse55i microscope (Nikon GmbH, Dussel?dorf, Germany) and a Fluoro Pro MP 5000 Camera 1326631 (Intas Science Imaging Instruments GmbH, Gottingen, Germany) at a 200-fold ?magnification. Images excited at 465?95 nm for positive cH2AX foci (red fluorescence) were merged with those excited at 330?80 nm for bisbenzimide (blue fluorescence). For quantification, 8 non-overlapping microscopic fields of renal cortex were analyzed by the cell image analysis software CellProfiler (Broad Institute, Cambridge, USA).StatisticsStatistical analysis was carried out using GraphPad Prism 4.0 (GraphPad Software, San Diego, CA, USA) or SPSS Statistics 19 (IBM, Ehningen, Germany). Each group consisted of 6 animals. All data are expressed as means 6 S.E.M. Group means were compared with an analysis of variance (ANOVA) followed by Tukey’s multiple comparison test. Values of p,0.05 were regarded as significant.AcknowledgmentsThanks are due to Sanwa_Cho., Japan for a free sample of SUPERGUMTM, and the staff of the Animal House of SQU for looking after the rats.Author ContributionsConceived and designed the experiments: BHA. Performed the experiments: IA-H SB AAS AN SS. Analyzed the data: BHA IA-H SB AAS AN SS NQ NS. Wrote the paper: BHA AN NS.
Next-generation sequencing (NGS) is changing dramatically our ability to analyze virus populations [1,2]. With NGS, many viral genomes can be analyzed in parallel in a single sequencing experiment [3], and by using deep coverage, even rare viral variants can be detected in genetically heterogeneous populations. Deep sequencing of intra-host virus populations is becoming an important tool for studying viruses with a growing number of applications [4], including, for example, drug resistance [5,6,7,8], immune escape [9,10], and epidemiology [11,12]. Most NGS-based studies assess viral diversity at each sequence position separately by inferring single-nucleotide variants (SNVs) from the read data. SNV calling is complicated by errors that can occur during sample preparation and sequencing, and statistical tests have been developed to distinguish technical errors from true biological SNVs [6,13,14,15]. Since all NGS technologies amplify and read out individual DNA molecules [3], the co-occurrence of mutations, or phasing, can also be assessed provided that they are observed on the same read. By considering entire reads, rather than individual SNVs, error correction can be significantly improved, and the structure of the virus population, i.e., the set of all viral haplotype sequences and their frequencies, can be inferred over genomic regions as long as the average read length [13,16]. The local haplotyp.