Figure 1.

Regulation of alternative splicing events by the interplay between trans-splicing factors and cis-regulatory elements within pre-mRNAs. Square 1 represents ESE (exonic splicing enhancer) or ISE (intronic splicing enhancer); square 2 represents ESS (exonic splicing silencer) or ISS (intronic splicing silencer); dotted line is applied to separate the exonic or intronic regulatory elements; blue rectangles represent the conserved exons; yellow rectangles represent the regulated exons; red and green ovals represent different splicing factors.