Mass spectrometry-based phosphoproteomics is undoubtedly one of the most powerful tools available for investigating the detailed molecular events that occur in response to cellular stimuli. While these experiments can routinely detect and quantify thousands of phosphorylated peptides, interpreting this data, and extracting biological meaning, remains challenging. In part, this is because comprehensive analysis can frequently involve many different software packages, web sites and databases resulting in a complicated and iterative process that is both prohibitive for non-experts and cumbersome and time-consuming for experienced researchers. Here, we present a substantial expansion to our phosphoproteomics data analysis website - ‘Phosphomatics’ – that incorporates a suite of new tools and resources for statistical and functional analysis that aim to simplify the process of extracting meaningful insights from experimental results.
Phosphomatics can natively import search and quantitation results from major search engines including MaxQuant and Proteome Discoverer and employs intuitive ‘wizards’ to guide user through data preprocessing routines such as filtering, normalization and transformation. A graphical platform of interactive univariate and multivariate analysis features is provided that allow subgroups of the uploaded data containing phosphosites of statistical interest to be created and interrogated through further functional analysis. For example, features are incorporated to assess hyperactivation of putative upstream kinases, consensus phosphorylation motifs for peptides groups, pathway/gene ontology enrichment and interaction networks. A range of databases have been integrated that, for example, provide ligand and inhibitor information for key proteins or highlight key modification sites known to be involved in functional state regulation. At each step, published literature is natively incorporated along with a ‘bibliography builder’ that allows references of interest to be assembled and exported in various formats. Taken together, these expanded features aim to provide a ‘one-stop-shop’ for phosphoproteomics data analysis.
Phosphomatics is freely available via the internet at: https://phosphomatics.com/