Structure of exon 10 and intron 10 of tau gene. Exon 10 is shown in capital letters and part of the franking intron 9 and intron 10 are shown in lowercase. The first half of exon 10 has three exonic splicing enhancers (SC35-like, PPE and ACE). A central exon splicing silencer (ESS) separates the 5' ESE elements from a less characterized ESE at the 3'-end of exon 10. Intron 10 elements include a bipartile intronic splicing silencer (ISS) and an adjacent intronic splicing modulator (ISM). In the interface between exon 10 and intron 10, there is a stem-loop structure. Mutations that cause an increase (red), decrease (dark green) or not yet known change (black) in the ratio of 4R/3R-tau are indicated. Triangles indicate deletion mutations.