FlyBase:GBrowse Help

Navigating around the Genome

Choosing a genome

The genome is set to D. melanogaster by default, but other Drosophila genomes are available using the Data Source box in the search panel.

Available genomes are:

• D. pseudoobscura

• D. ananaassae

• D. erecta

• D. grimshawi

• D. mojavensis

• D. persimilis

• D. sechelia

• D. simulans

• D. virilis

• D. wilistoni

• D. yakuba

Displaying a specific region of the genome

To select a specific region of the chosen genome to view, enter any of the following in the text field labeled "Landmark or Region". This box will accept:

• FlyBase symbols, e.g., cnn

• FlyBase IDs e.g., FBgn0000490

• Sequence locations e.g., X:6000..8000, 2L:80,000..100,000

To select a sub region of the region already displayed, click and drag along the coordinate scale in the detail panel. A pop-up box will appear that shows the coordinates of the region selected (rounded to the nearest mark on the coordinate scale at each end) and offers options to center the genome view on the selected region or to zoom in to the selected region; there is also an option to obtain the genomic sequence of the selected region in FASTA format.

To move to a different section of the chromosome, click on the chromosome scale in the Overview panel. The region of the chromosome that is currently displayed in the detail panel is indicated with two dotted lines.

Moving across the genome

Once a region of the genome is displayed there are two ways you can move across the genome from that location.

Using scroll buttons - Scroll defined distances left or right with the <<, <, > and >> buttons in the search panel. A pop up will indicate the distance that each button will scroll. In general, clicking the single arrow will move the view over by half the length displayed in the viewer and the double arrow will move the full distance, e.g. if the scroll/zoom box indicates "Show 10 kbp", a click on the single right arrow will move the view to the right by 5 kbp and a click on the double right arrow will move the view to the right by 10kbp.

Dragging the detail panel - drag the detail panel left or right to move across the genome. Note that the drag option works to move the screen for a limited distance in either direction equal to the extent in kbp displayed on the screen, e.g., if the scroll/zoom box indicates "Show 10 kbp", the view can be dragged for 10kb in either directon of the original view. If you wish to move further, use the scroll buttons to advance laterally and then the drag option will be reset.

Customizing the display

Zooming

Zoom in or out using the "Show XXX bp" menu in the search panel. The available options are:

• 100bp
• 200bp
• 1kbp
• 2kbp
• 5kbp
• 10kbp
• 20kbp
• 40kbp
• 70kbp
• 100kbp
• 200kbp

Press the - and + buttons either side of the menu to change the zoom level by 10%.

Centering

Click on the coordinate scale (at the top of the detail panel) to recenter the detail panel around the location you clicked.

Flipping the genome

To flip the browser display so that the minus strand points to the right, select the "flip" checkbox in the search panel.

Displaying restriction sites

Restriction sites can be displayed by choosing 'Annotate Restriction Sites" from the top right hand drop down box. Click 'Configure' to choose the restriction sites you would like to display.

Changing the order of the tracks

To change the order of the tracks in the display panel click on the track label and drag up or down.

Opening/closing panels

Click on the red add/minus sign at the top of each panel to open and close that panel.

Other display preferences

A number of other display preferences can be found in the Preferences tab including

• Showing/hiding the grid lines on the detail panel. These are displayed by default.
• Enabling/disabling caching of tracks.
• Show/hide tooltips. These are displayed by default.
• Changing the width of the image. The default image width is 800. Other options are 1024 and 2048.

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Choosing tracks

The default GBrowse view comprises a predetermined set of 10 tracks. For details of all of the tracks available see here

Selecting existing tracks

To select tracks go to the 'Select Tracks' tab and choose the tracks you would like to display.

Adding custom tracks

To add custom tracks go to the 'Custom Tracks' tab.

You have the option of adding tracks from text, from a URL or from a file.

For more information about how to add custom tracks see here

Customizing tracks

A set of icons is present above each track to the left of the track name that offer a variety of options. Mousing over an icon reveals the function of the icon. The functions of the icons are described here from left to right:

1. Favorites

2. Show or hide this track - toggling on this icon causes the data to show or be hidden from view but the track name and icons remains in the GBrowse view.

3. Turn off this track - clicking on this icon removes the corresponding track completely from view. To reinstate the track, go to the "Select Tracks" tab and re-select the track.

4. Share this track - clicking on this icon opens a pop-up box that provides instructions and the appropriate URLs for sharing a track with another user or exporting a track to a different GBrowse genome browser.

5. Download this track - clicking on this icon opens a pop-up box that allows one to download the data for either the region shown, the chromosome arm, or the entire data set in either FASTA, GFF3, or GenBank format.

6. Configure this track

7. About track - clicking on this icon opens a pop-up box with a link to a description of the data in the track at the GBrowse Tracks page and also gives you the option to download all of the data for the track in question.

Other useful features

Ruler

Clicking on the orange ruler icon in the top left corner of the "Details" panel brings up a vertical "ruler" that can be dragged across the GBrowse display and used to gauge the relative positions of features in different tiers. The coordinate corresponding to the central line of the ruler is displayed at the top of the ruler.

Links to report pages

Clicking on most genomic features displayed in the GBrowse genomic viewer leads to a detailed report of curated information connected to that feature; reports to the relevant genes, alleles, insertions, aberrations, and sequence features can be accessed in this way. cDNAs and ESTs link to GenBank sequence accession reports.

Accessing previous versions of the genome

The link "Go to Dmel R5.57 Archive Server" above the top right corner of the browser goes to the last FlyBase release containing genome Release 5 (R5) data. Clicking on the GBrowse link at the archived FlyBase site leads to a genome browser with the genomic data displayed relative to R5 coordinates. Previous releases can always be accessed from the Archive tab at the top of the page.