Streaming quantification for high-throughput sequencing
DescriptioneXpress is a streaming tool for quantifying the abundances of a set of target sequences from sampled subsequences. Example applications include transcript-level RNA-Seq quantification, allele-specific/haplotype expression analysis (from RNA-Seq), transcription factor binding quantification in ChIP-Seq, and analysis of metagenomic data. It is based on an online-EM algorithm that results in space (memory) requirements proportional to the total size of the target sequences and time requirements that are proportional to the number of sampled fragments. Thus, in applications such as RNA-Seq, eXpress can accurately quantify much larger samples than other currently available tools greatly reducing computing infrastructure requirements. eXpress can be used to build lightweight high-throughput sequencing processing pipelines when coupled with a streaming aligner (such as Bowtie), as output can be piped directly into eXpress, effectively eliminating the need to store read alignments in memory or on disk. In an analysis of the performance of eXpress for RNA-Seq data, it was observed that this efficiency does not come at a cost of accuracy. eXpress is more accurate than other available tools, even when limited to smaller datasets that do not require such efficiency. Moreover, like the Cufflinks program, eXpress can be used to estimate transcript abundances in multi-isoform genes. eXpress is also able to resolve multi-mappings of reads across gene families, and does not require a reference genome so that it can be used in conjunction with de novo assemblers such as Trinity, Oases, or Trans-ABySS. The underlying model is based on previously described probabilistic models developed for RNA-Seq but is applicable to other settings where target sequences are sampled, and includes parameters for fragment length distributions, errors in reads, and sequence-specific fragment bias. eXpress can be used to resolve ambiguous mappings in other high-throughput sequencing based applications. The only required inputs to eXpress are a set of target sequences and a set of sequenced fragments multiply-aligned to them. While these target sequences will often be gene isoforms, they need not be. Haplotypes can be used as the reference for allele-specific expression analysis, binding regions for ChIP-Seq, or target genomes in metagenomics experiments. eXpress is useful in any analysis where reads multi-map to sequences that differ in abundance.
878 other people were interested in this package here. The newest known version of this software is 1.5.2+dfsg-1+b2 (Information last updated about 1 hour ago.)
Upload new screenshots
Thanks for uploading more screenshots. Please note:
- Your screenshot should contain a typical scene when working with it.
- Take only a screenshot of the respective application and not of your whole desktop (unless the screenshot is meant for a window manager).
- Your screenshots must be in PNG format.
- You can upload multiple images at once.
- Your screenshot need to be approved by the moderators first. You will already see your screenshot but it will not be visible to others instantly. If moderators reject your upload you will get notified next time you visit this site (requires cookies).
- Images larger than 800x600 pixels will automatically be reduced. So don't try to capture too much detail in a screenshot. It may become unreadable. Shrink the applications window if possible.
- Screenshots are made public and can freely be used by anyone.
- Useful programs for making screenshots are shutter, ksnapshot (KDE), gimp, xwd or scrot. See the Debian wiki for more information on how to make screenshots under Debian.
- Please set your language to english so that everybody understands it. If you don't use english by default please start your application from a shell using after setting "export LANG=C".