Fig. 1.

Subsets of AS transitions are coregulated during specific times of mouse heart development. Total RNA was isolated from 6–20 pooled hearts at the indicated time points. RT-PCR analysis was carried out for 63 AS events. Data are expressed as the percentage inclusion (Upper) and as the percentage of total change (Lower) for variable regions that show increased (A) or decreased (B) inclusion during development. Alternative exons are numbered according to Ensembl, and sequences of variable regions are presented in Table S2. In at least 2 independent assays for all E14 and adult samples, the standard deviation was <5 percentage points.