IDENTIFICATION AND CHARACTERIZATION OF COMPONENTS OF THE YEAST SPLICEOSOME

The spliceosome is a complex, dynamic ribonucleoprotein (RNP) complex that undergoes numerous conformational changes during its assembly, activation, catalysis and disassembly. Defects in spliceosome assembly are thought to trigger active dissociation of faulty splicing complexes. A yeast genetic screen was performed to identify components of the putative discard pathway. This study found that weak mutant alleles of SPP382 suppress defects in several proteins required for spliceosome activation (Prp38p, Prp8p and Prp19p) as well as substrate mutations (weak branch point mutants). This evolutionary conserved protein had been found in both yeast and mammalian splicing complexes. However, its role in splicing had not been elucidated. This study focused on understanding the cellular role of Spp382p in splicing and particularl