Abstract

Motivation: Evolving technology has increased the focus on genomics. The combination of today’s advanced techniques with decades of molecular biology research has yielded huge amounts of pathway data. A standard, named the Systems Biology Graphical Notation (SBGN), was recently introduced to allow scientists to represent biological pathways in an unambiguous, easy-to-understand and efficient manner. Although there are a number of automated layout algorithms for various types of biological networks, currently none specialize on process description (PD) maps as defined by SBGN.Results: We propose a new automated layout algorithm for PD maps drawn in SBGN. Our algorithm is based on a force-directed automated layout algorithm called Compound Spring Embedder (CoSE). On top of the existing force scheme, additional heuristics employing new types of forces and movement rules are defined to address SBGN-specific rules. Our algorithm is the only automatic layout algorithm that properly addresses all SBGN rules for drawing PD maps, including placement of substrates and products of process nodes on opposite sides, compact tiling of members of molecular complexes and extensively making use of nested structures (compound nodes) to properly draw cellular locations and molecular complex structures. As demonstrated experimentally, the algorithm results in significant improvements over use of a generic layout algorithm such as CoSE in addressing SBGN rules on top of commonly accepted graph drawing criteria.Availability and implementation: An implementation of our algorithm in Java is available within ChiLay library (https://github.com/iVis-at-Bilkent/chilay).Contact: ugur@cs.bilkent.edu.tr or dogrusoz@cbio.mskcc.orgSupplementary information: Supplementary data are available at Bioinformatics online.

Highlights

  • Popular belief is that diagrams directly address people’s innate cognitive abilities (Larkin and Simon, 1987)

  • Handling process ports In order to equip process nodes with ports in Systems Biology Graphical Notation (SBGN)-process descriptions (PD) layout, without interfering with the existing physical system too much, we introduce new node and edge types (Figure 5)

  • For each measurement for a layout algorithm, 10 executions were performed and the average was taken since spring embedders start out from random initial positions, and this might highly affect the convergence speed

Read more

Summary

INTRODUCTION

Standard notations play an important role in communication and facilitate rapid development in many research areas. To address this issue in the field of systems biology, a group of modellers, biochemists and software engineers published the Systems Biology Graphical Notation (SBGN), which allows scientists to represent biological pathways and networks in an easy-to-understand and efficient way (Le Novere et al, 2009). It consists of three complementary languages: process descriptions (PD), activity flows (AF) and entity relationships (ER). CellDesigner (Funahashi et al, 2003) provides a rich set of generic layout algorithms, including one with compound support imported from a commercial library

Graphs and process description maps
Automated layout and CoSE
Rectangle packing and compaction
METHODS
IMPLEMENTATION AND RESULTS
CONCLUSION
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call