SUMMARY: Large-scale sharing of genomic quantification data requires standardized access interfaces. In this Global Alliance for Genomics and Health project, we developed RNAget, an API for secure access to genomic quantification data in matrix form. RNAget provides for slicing matrices to extract desired subsets of data and is applicable to all expression matrix-format data, including RNA sequencing and microarrays. Further, it generalizes to quantification matrices of other sequence-based genomics such as ATAC-seq and ChIP-seq. AVAILABILITY AND IMPLEMENTATION: https://ga4gh-rnaseq.github.io/schema/docs/index.html.

MOTIVATION: Reference sequences are essential in creating a baseline of knowledge for many common bioinformatics methods, especially those using genomic sequencing. RESULTS: We have created refget, a Global Alliance for Genomics and Health API specification to access reference sequences and sub-sequences using an identifier derived from the sequence itself. We present four reference implementations across in-house and cloud infrastructure, a compliance suite and a web report used to ensure specification conformity across implementations. AVAILABILITY AND IMPLEMENTATION: The refget specification can be found at: https://w3id.org/ga4gh/refget. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Motivation: Spatially clustered mutations within specific regions of protein structure are thought to result from strong positive selection for altered protein functions and are a common feature of oncoproteins in cancer. Although previous studies have used spatial substitution clustering to identify positive selection between pairs of proteins, the ability of this approach to identify functional shifts in protein phylogenies has not been explored. Results: We implemented a previous measure of spatial substitution clustering (the P3D statistic) and extended it to detect spatially clustered substitutions at specific branches of phylogenetic trees. We then applied the analysis to 423 690 phylogenetic branches from 9261 vertebrate protein families, and examined its ability to detect historical shifts in protein function. Our analysis identified 19 607 lineages from 5362 protein families in which substitutions were spatially clustered on protein structures at P3D < 0.01. Spatially clustered substitutions were overrepresented among ligand-binding residues and were significantly enriched among particular protein families and functions including C2H2 transcription factors and protein kinases. A small but significant proportion of branches with spatially clustered substitution also were under positive selection according to the branch-site test. Lastly, exploration of the top-scoring candidates revealed historical substitution events in vertebrate protein families that have generated new functions and protein interactions, including ancient adaptations in SLC7A2, PTEN, and SNAP25 . Ultimately, our work shows that lineage-specific, spatially clustered substitutions are a useful feature for identifying functional shifts in protein families, and reveal new candidates for future experimental study. Availability and Implementation: Source code and predictions for analyses performed in this study are available at: https://github.com/doxeylab/evoclust3d. Contact: [email protected]. Supplementary information: Supplementary data are available at Bioinformatics online.