Fig 6. Splicing combinations and cryptic spliceosome mechanism at the κ-casein gene (CSN3) Schematic representation of the aligned exon structure of the llama κ-casein gene (CSN3).
The top of the figure shows the two possible splicing combinations with (upper) and without (lower) the cryptic exon. The down part of the figure shows in details the sequence of cryptic exon 2 (in brackets) with the respective 5’- and 3’- intronic flanking regions. The branch point site is fully underlined and the bold adenine represent the main branch point (black triangle), followed by a polypyrimidine tract (Pyn) and the acceptor splice site (AS). The dotted-line and the white triangles represent additional polypyrimidine tracts and alternative branch points, respectively. The donor splice site (DS) for the following intron splicing is normally present.