title: Splicing factor Sub2p is required for nuclear mRNA   export through its interaction with Yra1p.
abstract: The yeast nuclear protein Yra1p is an essential export factor for mRNA. Yra1p interacts directly with the mRNA transport factor Mex67p/Mtr2p, which is associated with the nuclear pore. Here, we report a genetic interaction between YRA1 and SUB2, the gene for a DEAD box helicase involved in splicing. Mutation of SUB2 as well as its overexpression leads to a defect in mRNA export. Moreover, Yra1p and Sub2p bind directly to each other both in vivo and in vitro. Significantly, Sub2p and Mex67p/Mtr2p bind to the same domains of Yra1p, and the proteins compete for binding to Yra1p. Together, these data indicate that the spliceosomal component Sub2p is also important in mRNA export and may function to recruit Yra1p to the mRNA. Sub2p may then be displaced from Yra1p by the binding of Mex67p/Mtr2p, which participates in the export of mRNA through the nuclear pores.
authors.affiliation: BZH--Biochemie-Zentrum Heidelberg, Im Neuenheimer Feld 328, D-69120 Heidelberg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Strässer
authors.forename: E
authors.initials: E
authors.lastname: Hurt
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000502:physiology*; D000595:Amino Acid Sequence; D001665:Binding Sites; D001692:Biological Transport; D002467:Cell Nucleus / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005804:Genes, Lethal; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D029543:Nucleocytoplasmic Transport Proteins; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins
chemical_list: D005656:Fungal Proteins; C106898:MEX67 protein, S cerevisiae; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C105887:YRA1 protein, S cerevisiae; D000251:Adenosine Triphosphatases; C027900:RNA-dependent ATPase