Hierarchy for 5′ splice site preference determined in vivo

The relationship between preferences among alternative 5′ splice sites and their sequences has been investigated for 37 sequences by assessing their use in splicing relative to the 5′ splice site of IVS-2 of rabbit β-globin. There are strong correlations between the intrinsic strength of a 5′ splice site and both the extent to which it resembles the consensus sequence and the calculated stability of its interactions with U1 small nuclear RNA. However, present methods of calculating either of the latter values do not allow predictions to be made of the relative preferences among a small number of sequences.