The target of the DEAH-box NTP triphosphatase Prp43 in Saccharomyces cerevisiae spliceosomes is the U2 snRNP-intron interaction
- Max-Planck-Institute of Biophysical Chemistry, Germany
- Max Planck Institute for Biophysical Chemistry, Germany
- Georg August University of Göttingen, Germany
Abstract
The DEAH-box NTPase Prp43 and its cofactors Ntr1 and Ntr2 form the NTR complex and are required for disassembling intron-lariat spliceosomes (ILS) and defective earlier spliceosomes. However, the Prp43 binding site in the spliceosome and its target(s) are unknown. We show that Prp43 fused to Ntr1's G patch motif (Prp43_Ntr1GP) is as efficient as the NTR in ILS disassembly, yielding identical dissociation products and recognizing its natural ILS target even in the absence of Ntr1's C-terminal-domain (CTD) and Ntr2. Unlike the NTR, Prp43_Ntr1GP disassembles earlier spliceosomal complexes (A, B, Bact), indicating that Ntr2/Ntr1-CTD prevents NTR from disrupting properly assembled spliceosomes other than the ILS. The U2 snRNP-intron interaction is disrupted in all complexes by Prp43_Ntr1GP, and in the spliceosome contacts U2 proteins and the pre-mRNA, indicating that the U2 snRNP-intron interaction is Prp43's major target.
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© 2016, Fourmann et al.
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The target of the DEAH-box NTP triphosphatase Prp43 in Saccharomyces cerevisiae spliceosomes is the U2 snRNP-intron interaction
eLife 5:e15564.
https://doi.org/10.7554/eLife.15564
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