Cwc24p is a general Saccharomyces cerevisiae splicing factor required for the stable U2 snRNP binding to primary transcripts

PLoS One. 2012;7(9):e45678. doi: 10.1371/journal.pone.0045678. Epub 2012 Sep 24.

Abstract

Splicing of primary transcripts is an essential process for the control of gene expression. Specific conserved sequences in premature transcripts are important to recruit the spliceosome machinery. The Saccharomyces cerevisiae catalytic spliceosome is composed of about 60 proteins and 5 snRNAs (U1, U2, U4/U6 and U5). Among these proteins, there are core components and regulatory factors, which might stabilize or facilitate splicing of specific substrates. Assembly of a catalytic complex depends on the dynamics of interactions between these proteins and RNAs. Cwc24p is an essential S. cerevisiae protein, originally identified as a component of the NTC complex, and later shown to affect splicing in vivo. In this work, we show that Cwc24p also affects splicing in vitro. We show that Cwc24p is important for the U2 snRNP binding to primary transcripts, co-migrates with spliceosomes, and that it interacts with Brr2p. Additionally, we show that Cwc24p is important for the stable binding of Prp19p to the spliceosome. We propose a model in which Cwc24p is required for stabilizing the U2 association with primary transcripts, and therefore, especially important for splicing of RNAs containing non-consensus branchpoint sequences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA Primers
  • Immunoprecipitation
  • Protein Binding
  • RNA Splicing*
  • RNA, Messenger / metabolism*
  • Real-Time Polymerase Chain Reaction
  • Recombinant Proteins / metabolism
  • Ribonucleoprotein, U2 Small Nuclear / metabolism*
  • Saccharomyces cerevisiae Proteins / physiology*

Substances

  • DNA Primers
  • RNA, Messenger
  • Recombinant Proteins
  • Ribonucleoprotein, U2 Small Nuclear
  • Saccharomyces cerevisiae Proteins

Grant support

This work was supported by a grant from Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP (09/52826-4 to C.C.O.). P.P.C. was recipient of a FAPESP fellowship (09/52176-0). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.