The Sliced View panel displays an alternative view of items selected in the main display. It is especially useful with mammalian genes which can span vast regions of genomic sequence but which are comprised mostly of intronic sequence. The sliced view aims to give you a higher level summary of gene structures by condensing the intronic regions and allowing you to focus on the exons, relative to each other. For details about using this feature, see Changing the ViewAppearance of Tracks.
The following image shows how this works. The top panel of the IGB main display window shows the normal, non-spliced view of a region containing overlapping genes from a cow, GBN4, which contains an enormous five prime intron that completely encompasses another gene, ZNF639, which encodes a zinc finger protein. The Sliced View panel on the bottom shows these same two genes, but with the intronic sequences reduced to 100bp. The places where the slices were made appear as black hash marks below the axis in the Sliced View. Note how the sliced view makes it easy to see both gene structures simultaneously, whereas in the main view ZNF639 is so small it is impossible to even see the number of exons it contains.
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Another feature that the Sliced View panel supports is finding open reading frames (ORFs) and stop codons. For details on using this function, please see Changing the ViewAppearance of TracksAdditional and Alternate Views of Annotations.