UnigeneFinder: An automated pipeline for gene calling from transcriptome assemblies without a reference genome

Abstract

For most species in nature, transcriptome data is much more readily available than genome data. Without a reference genome, however, gene calling is cumbersome and inaccurate due to the high degree of redundancy in de novo transcriptome assemblies. To simplify and increase the accuracy of de novo transcriptome assembly in the absence of a reference genome, we developed UnigeneFinder. Combining several clustering methods, UnigeneFinder substantially reduces the redundancy typical of raw transcriptome assemblies. This pipeline offers an effective solution to the problem of inflated transcript numbers, achieving a closer representation of the actual underlying genome. UnigeneFinder performs comparably or better, compared to existing tools, on plant species with varying genome complexities. UnigeneFinder is the only available transcriptome redundancy solution that fully automates the generation of primary transcript, coding region, and protein sequences, analogous to those available for high quality reference genomes. These features, coupled with the pipelines cross-platform implementation and focus on automation and an accessible user interface, make UnigeneFinder a useful tool for many downstream sequence-based analyses in non-model organisms lacking a reference genome, including differential gene expression analysis, accurate ortholog identification, functional enrichments, and evolutionary analyses. UnigeneFinder also runs efficiently both on high-performance computing (HPC) systems and personal computers, further reducing barriers to use.