I'm trying to download reference annotation data --specifically bed files for exons/introns in the mm10 genome, and I saw this question here saying that you can download mm10_exons.bed file from UCSC using the Table browser tool, however I need some help with the interface.

I went to https://genome.ucsc.edu/cgi-bin/hgTables and selected Clade:mammal --> genome:mouse --> assembly:mm10 --> group: Genes and Gene predictions ... but after that I'm lost. There's various Tracks and tables to choose from, but nowhere do I see an option for "exons". Is there an option I'm not seeing to download, say, the list of exons throughout the genome ?

Thanks for any help you can offer.

Edit: solution: reply suggests converting gff, which is probably possible, but I found it hard to follow, and the solution below more direct and less error-susceptible: [ paraphrasing the guide at https://genome.ucsc.edu/training/vids/transcript08.pdf ]

To begin, navigate to the browser at genome.ucsc.edu. In the upper left hand corner, you can find two links that lead to the Browser database. pick mouse mm10 database. Using the pull-down menu at the top of the graphic, we go to the Table Browser (or just type " tt "). The Table Browser defaults to the genes and gene prediction group, the UCSC genes track, and the primary table of known gene for that track.

The Table Browser gives us a choice of a number of different output formats. Select "BED (Browser Extensible Display)" output format. The “get output” button gives us a page where we can choose a number of different options. We will take the “Exons” option, give it a name and then and “get BED.” You _can_ select everything on the screen, copy and paste elsewher, but it's easier to right-click and "save page as..." to download.