iRefR: an R package to manipulate the iRefIndex consolidated protein interaction database

<p>Abstract</p> <p>Background</p> <p>The iRefIndex addresses the need to consolidate protein interaction data into a single uniform data resource. iRefR provides the user with access to this data source from an R environment.</p> <p>Results</p> <p>The iRefR package includes tools for selecting specific subsets of interest from the iRefIndex by criteria such as organism, source database, experimental method, protein accessions and publication identifier. Data may be converted between three representations (MITAB, edgeList and graph) for use with other R packages such as igraph, graph and RBGL.</p> <p>The user may choose between different methods for resolving redundancies in interaction data and how n-ary data is represented. In addition, we describe a function to identify binary interaction records that possibly represent protein complexes. We show that the user choice of data selection, redundancy resolution and n-ary data representation all have an impact on graphical analysis.</p> <p>Conclusions</p> <p>The package allows the user to control how these issues are dealt with and communicate them via an R-script written using the iRefR package - this will facilitate communication of methods, reproducibility of network analyses and further modification and comparison of methods by researchers.</p

Genomorama: genome visualization and analysis

<p>Abstract</p> <p>Background</p> <p>The ability to visualize genomic features and design experimental assays that can target specific regions of a genome is essential for modern biology. To assist in these tasks, we present Genomorama, a software program for interactively displaying multiple genomes and identifying potential DNA hybridization sites for assay design.</p> <p>Results</p> <p>Useful features of Genomorama include genome search by DNA hybridization (probe binding and PCR amplification), efficient multi-scale display and manipulation of multiple genomes, support for many genome file types and the ability to search for and retrieve data from the National Center for Biotechnology Information (NCBI) Entrez server.</p> <p>Conclusion</p> <p>Genomorama provides an efficient computational platform for visualizing and analyzing multiple genomes.</p

DNA Methylation Signature for EZH2 Functionally Classifies Sequence Variants in Three PRC2 Complex Genes.

Weaver syndrome (WS), an overgrowth/intellectual disability syndrome (OGID), is caused by pathogenic variants in the histone methyltransferase EZH2, which encodes a core component of the Polycomb repressive complex-2 (PRC2). Using genome-wide DNA methylation (DNAm) data for 187 individuals with OGID and 969 control subjects, we show that pathogenic variants in EZH2 generate a highly specific and sensitive DNAm signature reflecting the phenotype of WS. This signature can be used to distinguish loss-of-function from gain-of-function missense variants and to detect somatic mosaicism. We also show that the signature can accurately classify sequence variants in EED and SUZ12, which encode two other core components of PRC2, and predict the presence of pathogenic variants in undiagnosed individuals with OGID. The discovery of a functionally relevant signature with utility for diagnostic classification of sequence variants in EZH2, EED, and SUZ12 supports the emerging paradigm shift for implementation of DNAm signatures into diagnostics and translational research

Bluejay 1.0: genome browsing and comparison with rich customization provision and dynamic resource linking

<p>Abstract</p> <p>Background</p> <p>The Bluejay genome browser has been developed over several years to address the challenges posed by the ever increasing number of data types as well as the increasing volume of data in genome research. Beginning with a browser capable of rendering views of XML-based genomic information and providing scalable vector graphics output, we have now completed version 1.0 of the system with many additional features. Our development efforts were guided by our observation that biologists who use both gene expression profiling and comparative genomics gain functional insights above and beyond those provided by traditional per-gene analyses.</p> <p>Results</p> <p>Bluejay 1.0 is a genome viewer integrating genome annotation with: (i) gene expression information; and (ii) comparative analysis with an unlimited number of other genomes in the same view. This allows the biologist to see a gene not just in the context of its genome, but also its regulation and its evolution. Bluejay now has rich provision for personalization by users: (i) numerous display customization features; (ii) the availability of waypoints for marking multiple points of interest on a genome and subsequently utilizing them; and (iii) the ability to take user relevance feedback of annotated genes or textual items to offer personalized recommendations. Bluejay 1.0 also embeds the Seahawk browser for the Moby protocol, enabling users to seamlessly invoke hundreds of Web Services on genomic data of interest without any hard-coding.</p> <p>Conclusion</p> <p>Bluejay offers a unique set of customizable genome-browsing features, with the goal of allowing biologists to quickly focus on, analyze, compare, and retrieve related information on the parts of the genomic data they are most interested in. We expect these capabilities of Bluejay to benefit the many biologists who want to answer complex questions using the information available from completely sequenced genomes.</p

A specific DNA methylation signature associated with NSD1+/- mutations in Sotos syndrome reveals a significant genome-wide loss of DNA methylation (DNAm) targeting CGs in regulatory regions of key developmental genes

Sotos syndrome (SS) is characterized by somatic overgrowth and intellectual disability. Most SS cases (>75%) have mutations in NSD1 (nuclear receptor-binding SET domain protein 1). NSD1 binds near promoter elements and regulates transcription initiation and elongation via interactions with H3-K36Me and RNA polymerase II. To determine if NSD1 mutations impact stable epigenetic marks such as DNA methylation (DNAm), we compared DNAm in peripheral blood DNA from SS cases with NSD1 mutations (NSD1+/-; n=20) to controls (n=30) using the Illumina Infinium450methylation BeadChip. Differential DNAm analysis using non-parametric statistics (with correction for multiple testing) coupled with permutation analyses identified a surprisingly high number (n=2157) of differentially methylated (DM) CG sites (with >20% difference in DNAm) between SS and controls. These sites were distributed across the genome; 95% demonstrated loss of DNAm. Using unsupervised hierarchical clustering of the 2157 DM CG sites, all SS cases with NSD1 +/- clustered as a distinct group separate from controls. Moreover, DNAm at these sites clearly distinguished SS (NSD1+/-) from Weaver syndrome (EZH2+/-, n=5), another overgrowth syndrome which has considerable phenotypic overlap with SS. These results suggest that these DM CG sites constitute a DNAm signature that is specific for NSD1+/-. Also, the DNAm signature was successfully used to reclassify NSD1 variants of unknown significance (VUS) in six cases of SS into functionally damaging (n=1) and non-pathogenic (n=5) variants. The majority of these DM CGs mapped to enhancers and CpG island shores. Analysis of ChIP-seq data showed that NSD1+/- specific CG sites are associated with reduced H3K36me3 marks in both normal blood and embryonic stem cells. Also, Ingenuity analysis showed enrichment in neural and cellular development pathways (p<0.001). We then searched for binding motifs enriched in these NSD1+/- DNAm targets using MEME and JASPAR CORE database; SP1 was the most enriched with binding sites in 41% of the targets (NCOR=0.62). This is the first report of an NSD1+/- specific DNAm signature in SS and that loss-of-function mutations in NSD1 can deregulate the intricate transcriptional balance of key developmental genes. Further elucidation of this signature will significantly impact our understanding of the molecular pathophysiology of SS and identify the specific molecular targets for NSD1 that govern its action in early development.link_to_OA_fulltex