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Classic quick-start guide

Reference Sequences

Before loading annotation data, format your reference sequences for JBrowse using bin/prepare-refseqs.pl.

For FASTA format sequence files

bin/prepare-refseqs.pl --fasta docs/tutorial/data_files/volvox.fa

For sequences already stored in a Bio::DB::* database, you can use prepare-refseqs.pl with a biodb-to-json.pl config, see here for details.

bin/prepare-refseqs.pl --conf docs/tutorial/conf_files/volvox.json

Genomic annotations and features

JBrowse can import feature data from flat files, or from databases that have Bio::DB::* Perl interfaces.

bin/flatfile-to-json.pl

If you have flat files like GFF3 or BED, it is usually best to use bin/flatfile-to-json.pl to import them. bin/flatfile-to-json.pl accepts many different command-line settings that can be used to customize the appearance of the new track. Run bin/flatfile-to-json.pl --help to see a description of the available settings.

bin/flatfile-to-json.pl --gff path/to/my.gff3 --trackType CanvasFeatures --trackLabel mygff

bin/biodb-to-json.pl

If you have a genomic annotation database such as Chado, Bio::DB::SeqFeature::Store, or Bio::DB::GFF, then you can use JBrowse's biodb-to-json.pl. You use bin/biodb-to-json.pl with a configuration file (the format of which is documented here).

bin/biodb-to-json.pl --conf docs/tutorial/conf_files/volvox.json

Next-gen reads (BAM)

JBrowse can display alignments directly from BAM files, with no pre-processing necessary. To use, download the BAM file and BAM index into your data folder and you can manually edit text snippets into tracks.conf

[tracks.alignments]
storeClass = JBrowse/Store/SeqFeature/BAM
urlTemplate = myfile.bam
category = NGS
type = JBrowse/View/Track/Alignments2
key = BAM alignments from SEQ1654

Then, you will have a data structure that looks like

data/myfile.bam
data/myfile.bam.bai
data/tracks.conf

Where tracks.conf contains this above config, and then myfile.bam will be located relative to the location of tracks.conf so since they are in the same directory, it does not need any additional path qualifications. Note that urlTemplate can be a full URL path

Also note: BAM files are required to be sorted and indexed (i.e. have a corresponding .bai file or .csi file. If it is .csi, then the csiUrlTemplate can be used. If it is .bai, then it will automatically be located as <yourbamfile.bam> with .bai added on the end).

Next-gen read track types

JBrowse has two main track types that are designed especially for use with BAM data:

Alignments2

Shows individual alignments from the BAM file, as well as insertions, deletions, skipped regions, and SNPs encoded in the BAM's MD or CIGAR fields.

SNPCoverage

Shows a coverage histogram plot, with colored bars showing the locations of base-level mismatches and possible SNPs in the reads. To use them, set type = Alignments2 or type = SNPCoverage in the track configuration.

Index Names

After loading feature data, to let users find features by typing feature names or IDs in the autocompleting search box, a special index of feature names must be generated using bin/generate-names.pl.

bin/generate-names.pl -v

Note: You need to re-run bin/generate-names.pl to add new feature names to the index every time you add new annotations to JBrowse using any of the *-to-json.pl scripts.

Also note: the track types that are indexed by bin/generate-names.pl include

  • GFF, GBK, BED loaded via flatfile-to-json.pl. By default "ID", "Name", and "Alias" are indexed. Note that --nameAttributes can be used to index additional fields
  • Features from biodb-to-json.pl
  • VCF tabix files and GFF3 tabix files (their "ID" and "Name" field from GFF are indexed and only ID from VCF are indexed)

BAM reads and BigWigs are not indexed by generate-names.pl

Quantitative tracks (BigWig and Wiggle)

JBrowse can display alignments directly from BigWig files, with no pre-processing necessary. Simply add a stanza with the relative URL of the file to your data/tracks.conf file, of the form:

[ tracks.my-bigwig-track ]
storeClass = JBrowse/Store/SeqFeature/BigWig
urlTemplate = myfile.bw
type = JBrowse/View/Track/Wiggle/XYPlot
key = Coverage plot of NGS alignments from XYZ

JBrowse has two track types that are designed especially for use with quantitative data:

JBrowse/View/Track/Wiggle/XYPlot

Shows quantitative data as a bar graph. See the JBrowse wiki for configuration options.

JBrowse/View/Track/Wiggle/Density

Shows quantitative data as a "heatmap" plot, which by default draws regions with positive scores as progressively more intense blue, and negative scores as progressively more intense red. See the JBrowse wiki for configuration options, including how to change the color-change point (bicolor_pivot), and the colors.

To use them, set type = JBrowse/View/Track/Wiggle/XYPlot or type = JBrowse/View/Track/Wiggle/Density in the track configuration.

Troubleshooting

Sometimes things just don't go well. It seems like nothing is ever as easy as it should be. Here are several resources you can use if it turns out that this guide is not enough to get JBrowse working for you.

  • JBrowse FAQ - The FAQ contains extended documentation on many aspects JBrowse, including troubleshooting tips.
  • Mailing list gmod-ajax@lists.sourceforge.net - send an email to this mailing address and/or subscribe. If it is related to just getting started with jbrowse, please attach the setup.log file that is generated by setup.sh
  • GitHub at GMOD/jbrowse - This is preferably for actual JBrowse issues and feature requests but some help issues can be addressed here too :)
  • Gitter channel at https://gitter.im/GMOD/jbrowse

Conclusion

Good luck and enjoy JBrowse!