
Dim1p Is Required for Efficient Splicing and Export of mRNA Encoding Lid1p, a Component of the Fission Yeast Anaphase-Promoting Complex
Author(s) -
Robert H. Carnahan,
Anna Feoktistova,
Liping Ren,
Sherry Niessen,
John R. Yates,
Kathleen L. Gould
Publication year - 2005
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.4.3.577-587.2005
Subject(s) - rna splicing , schizosaccharomyces pombe , biology , anaphase , microbiology and biotechnology , schizosaccharomyces , mitosis , snrnp , messenger rna , saccharomyces cerevisiae , precursor mrna , genetics , mitotic exit , protein splicing , yeast , rna , gene , chromosome
Schizosaccharomyces pombe Dim1p is required for maintaining the steady-state level of the anaphase-promoting complex or cyclosome (APC/C) component Lid1p and thus for maintaining the steady-state level and activity of the APC/C. To gain further insight into Dim1p function, we have investigated the mechanism whereby Dim1p influences Lid1p levels. We show that S. pombe cells lacking Dim1p or Saccharomyces cerevisiae cells lacking its ortholog, Dib1p, are defective in generalized pre-mRNA splicing in vivo, a result consistent with the identification of Dim1p as a component of the purified yeast U4/U6.U5 tri-snRNP complex. Moreover, we find that Dim1p is part of a complex with the splicing factor Prp1p. However, although Dim1p is required for efficient splicing of lid1(+) pre-mRNA, circumventing the necessity for this particular function of Dim1p is insufficient for restoring normal Lid1p levels. Finally, we provide evidence that Dim1p also participates in the nuclear export of lid1(+) mRNA and that it is likely the combined loss of both of these two Dim1p functions which compromises Lid1p levels in the absence of proper Dim1p function. These data indicate that a mechanism acting at the level of mRNA impacts the functioning of the APC/C, a critical complex in controlling mitotic progression.