POINeT provides a straightforward viewer with sufficient functionalities. No additional software installations are required. Networks and tissue-specific expression profiles can be visualized directly in the browser. The viewer supports zoom and pan of networks. The concept of geographic information system (GIS) was introduced. Different output results were defined as different layers. Through the selection of different layers, ppi-QQPPI, ppi-GOPPI and ppi-InterologsPPI can be displayed individually or as a merged network, ppi-FilteredPPI. The labels on each layer can also be turned on/off, or labelling selected nodes. Finally, nodes can be selected to display associated interactions, PubMed IDs, and Gene Ontology annotations, and provide the links to external databases. Also, POINeT treats tissue-specific expression values as attributes of nodes in the network. Using the concept of layers, different tissue expressions can be selected and displayed for the same nodes, and facilitate analysis and comparison of these expression profiles. Network viewer provided by POINeT permits user to observe gene expression levels of the same PPI network in different tissue types.
Figure - Non-Small Cell Lung Carcinoma PPI network filtered by different tissue expression profiles. PPIs filtered by gene expression profiles. Expression levels of nodes are represented by different levels of greys. Query nodes are marked with squares. The colours of edges denotes different types of interactions: interactions between two query proteins (black), interaction between nodes sharing the same GO terms (red), interactions conserved in other species (greed). Only interactions between nodes exceeding user defined expression threshold are retained.