PubMed:8647433 JSONTXT

{"project":"AIMed","denotations":[{"id":"T1","span":{"begin":20,"end":26},"obj":"protein"},{"id":"T2","span":{"begin":224,"end":230},"obj":"protein"},{"id":"T3","span":{"begin":235,"end":241},"obj":"protein"},{"id":"T4","span":{"begin":244,"end":250},"obj":"protein"},{"id":"T5","span":{"begin":348,"end":354},"obj":"protein"},{"id":"T6","span":{"begin":377,"end":383},"obj":"protein"},{"id":"T7","span":{"begin":517,"end":523},"obj":"protein"},{"id":"T8","span":{"begin":656,"end":662},"obj":"protein"},{"id":"T9","span":{"begin":798,"end":804},"obj":"protein"},{"id":"T10","span":{"begin":844,"end":850},"obj":"protein"},{"id":"T11","span":{"begin":894,"end":900},"obj":"protein"},{"id":"T12","span":{"begin":931,"end":937},"obj":"protein"},{"id":"T13","span":{"begin":974,"end":980},"obj":"protein"}],"text":"The splicing factor U2AF35 mediates critical protein-protein interactions in constitutive and enhancer-dependent splicing.\nThe splicing factor U2AF (U2 snRNP auxiliary factor) is a heterodimer with subunits of 65 and 35 kD (U2AF65 and U2AF35). U2AF65 binds specifically to 3' splice sites, but previous studies failed to demonstrate a function for U2AF35. Here, we report that U2AF35 is required for constitutive splicing and also functions as a mediator of enhancer-dependent splicing. Nuclear extracts deficient in U2AF35 were inactive; however, both constitutive and enhancer-dependent splicing could be restored by the addition of purified recombinant U2AF35. In vitro protein-RNA interaction studies with pre-mRNAs containing either a constitutive or regulated splicing enhancer revealed that U2AF35 directly mediates interactions between U2AF65 and proteins bound to the enhancers. Thus, U2AF35 functions as a bridge between U2AF65 and the enhancer complex to recruit U2AF65 to the adjacent intron."}