bioRxiv Science⌕ Search

Biology subjects

Freese, N. H.

Publications and source records attributed to Freese, N. H..

3 recordsLinked to original sources

Track Hub Quickload Translator: Convert Track Hub or Quickload data for viewing in the UCSC Genome Browser or the Integrated Genome Browser

Summary: Genome browsers are essential for understanding genomic data in detail but use incompatible data repository formats and access protocols, limiting their use. We present a new web application Hub Facade that translates the Track Hub format used by the UCSC Genome Browser into the Quickload format used by the Integrated Genome Browser (IGB), and vice versa. We used the Facade's translation capability to write a single-page web application for IGB users to search and add UCSC-curated Hubs to IGB for exploration and visual analysis. We created a new IGB App (GenArk Genomes) that uses the Facade to automate importing genome assemblies from GenArk, a Hub-based repository with nearly 50,000 genomes hosted by the UCSC Genome Browser team. An example use case investigating alternative splicing of human gene MEOX1 shows how using both browsers to view the same data via the Hub Facade promotes understanding and discovery. Availability and Implementation: Hub Facade is free, open-source software deployed at translate.bioviz.org. Code is available from git repositories at [bitbucket.org|github.com]/lorainelab/hub-facade. The use case is available as Supplemental File 1.

bioinformatics↗

Genomic targets of HOP2 are enriched for features found at recombination hotspots

HOP2 is a conserved protein that plays a positive role in homologous chromosome pairing and a separable role in preventing illegitimate connections between nonhomologous chromosome regions during meiosis. We employed ChIP-seq to discover that Arabidopsis HOP2 binds along the length of all chromosomes, except for centromeric and nucleolar organizer regions, and no binding sites were detected in the organelle genomes. A large number of reads were assigned to the HOP2 locus itself, yet TAIL-PCR and SNP analysis of the aligned sequences indicate that many of these reads originate from the transforming T-DNA, supporting the role of HOP2 in preventing nonhomologous exchanges. The 292 ChIP-seq peaks are largely found in promoter regions and downstream from genes, paralleling the distribution of recombination hotspots, and motif analysis revealed that there are several conserved sequences that are also enriched at crossover sites. We conducted coimmunoprecipitation of HOP2 followed by LC-MS/MS and found enrichment for several proteins, including some histone variants and modifications that are also known to be associated with recombination hotspots. We propose that HOP2 may be directed to chromatin motifs near double strand breaks, where homology checks are proposed to occur.

plant biology↗

BioViz Connect: Web application linking CyVerse cloud resources to genomic visualization in the Integrated Genome Browser

Genomics researchers do better work when they can interactively explore and visualize data. However, due to the vast size of experimental datasets, researchers are increasingly using powerful, cloud-based systems to process and analyze data. These remote systems, called science gateways, offer user-friendly, Web-based access to high performance computing and storage resources, but typically lack interactive visualization capability. In this paper, we present BioViz Connect, a middleware Web application that links the CyVerse science gateway to the Integrated Genome Browser (IGB), a highly interactive native application implemented in Java that runs on the users personal computer. Using BioViz Connect, users can (i) stream data from the CyVerse data store into IGB for visualization, (ii) improve the IGB user experience for themselves and others by adding IGB specific metadata to CyVerse data files, including genome version and track appearance, and (iii) run compute-intensive visual analytics functions on CyVerse infrastructure to create new datasets for visualization in IGB or other applications. To demonstrate how BioViz Connect facilitates interactive data visualization, we describe an example RNA-Seq data analysis investigating how heat and desiccation stresses affect gene expression in the model plant Arabidopsis thaliana. Lastly, we discuss limitations of the technologies used and suggest opportunities for future work. BioViz Connect is available from https://bioviz.org.

bioinformatics↗