The SNT309 gene was identified via a mutation that causes lethality of cells in combination with a prp19 mutation. We showed previously that Snt309p is a component of the Prp19p-associated complex and that Snt309p, like Prp19p, is associated with the spliceo-some immediately after or concomitantly with dissociation of U4 from the spliceosome. We show here that extracts prepared from the SNT309-deleted strain (ΔSNT309) were defective in splicing but could be complemented by addition of the purified Prp19p- associated complex. Isolation of the Prp19p-associated complex from ΔSNT309 extracts indicated that the complex was destabilized in the absence of Snt309p and dissociated on affinity chromatography, suggesting a role of Snt309p in stabilization of the Prp19p-associated complex. Addition of the affinity-purified Prp19p-Snt309p binary complex to ΔSNT309 extracts could reconstitute the Prp19p-associated complex. Genetic analysis further suggests that Snt309p plays a role in modulating interactions of Prp19p with other associated components to facilitate formation of the Prp19p-associated complex. A model for how Snt309p modulates such interactions is proposed.
|Number of pages||6|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|Publication status||Published - 1999 May 11|
All Science Journal Classification (ASJC) codes