Activation and repression functions of an SR splicing regulator depend on exonic versus intronic-binding position.

ABSTRACT: SR proteins and related factors play widespread roles in alternative pre-mRNA splicing and are known to promote splice site recognition through their Arg-Ser-rich effector domains. However, binding of SR regulators to some targets results in repression of splice sites through a distinct mechanism. Here, we investigate how activated and repressed targets of the Drosophila SR regulator Transformer2 elicit its differing effects on splicing. We find that, like activation, repression affects early steps in the recognition of splice sites and spliceosome assembly. Repositioning of regulatory elements reveals that Tra2 complexes that normally repress splicing from intronic positions activate splicing when located in an exon. Protein tethering experiments demonstrate that this position dependence

SUBMITTER: Shen M 

PROVIDER: S-EPMC3245930 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature