Trinity

General information

2.1.1 release. Trinity, represents a novel method for the efficient and robust de novo reconstruction of transcriptomes from RNA-seq data. Trinity combines three independent software modules: Inchworm, Chrysalis, and Butterfly, applied sequentially to process large volumes of RNA-seq reads. Trinity partitions the sequence data into many individual de Bruijn graphs, each representing the transcriptional complexity at at a given gene or locus, and then processes each graph independently to extract full-length splicing isoforms and to tease apart transcripts derived from paralogous genes. Briefly, the process works like so:

  • Inchworm assembles the RNA-seq data into the unique sequences of transcripts, often generating full-length transcripts for a dominant isoform, but then reports just the unique portions of alternatively spliced transcripts.
  • Chrysalis clusters the Inchworm contigs into clusters and constructs complete de Bruijn graphs for each cluster. Each cluster represents the full transcriptonal complexity for a given gene (or sets of genes that share sequences in common). Chrysalis then partitions the full read set among these disjoint graphs.
  • Butterfly then processes the individual graphs in parallel, tracing the paths that reads and pairs of reads take within the graph, ultimately reporting full-length transcripts for alternatively spliced isoforms, and teasing apart transcripts that corresponds to paralogous genes.

How to use

You can use the

send_trinity

command to submit jobs to the queue system. After answering few questions a script will be created and submitted to the queue system. For advanced users it can be used to generate a sample script.

Performance

Trinity can be run in parallel but it is not very efficient above 4 cores with low performance, as can be seen in the the table. Trinity consumes high amounts of RAM.

Performance of Trinity
Cores  1 4 8 12
Time 5189 2116 1754 1852
Speddup 1 2.45 2.96 2.80
Efficiency (%)  100 61 37 23

 

More information

Trinity web page.