The yeast nucleoporin rip1p contributes to multiple export pathways with no essential role for its FG-repeat region.
The FG-repeat domain of the yeast Rip1 protein (Rip1p) was identified initially as a possible target for the nuclear export signal (NES) of the HIV-1 Rev protein in a yeast two-hybrid assay. Rip1p is inessential, associated with nuclear pore complexes, and structurally related to the FG-nucleoporin family of pore proteins. It contributes to HIV-1 Rev-mediated RNA export and is also important for the export of heat shock RNAs at 42 degrees C. We show here that Rip1p is essential for the export of heat shock RNAs, and this function is fulfilled by the unique carboxyl terminus of Rip1p with no substantial contribution from the FG-repeat region. Genetic interactions between Rip1p and the RNA export mediator Gle1p are described, which support a role of the carboxyl terminus of Rip1p in poly(A)+ RNA export. Finally, this domain of Rip1p also contributes to Rev-mediated RNA export. The data suggest that Rip1p promotes the nuclear export of different classes of substrates by contributing to optimal pore function.
Stutz
F
F
Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, Massachusetts 02254, USA.
Kantor
J
J
Zhang
D
D
McCarthy
T
T
Neville
M
M
Rosbash
M
M
D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism*; D017931:DNA Primers; D015694:Gene Products, rev / Q000096:biosynthesis / Q000378:metabolism*; D005838:Genotype; D015497:HIV-1 / Q000235:genetics*; D009685:Nuclear Envelope / Q000378:metabolism; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins / Q000378:metabolism*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012331:RNA, Fungal / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction; D054321:rev Gene Products, Human Immunodeficiency Virus
D017931:DNA Primers; D015694:Gene Products, rev; C109212:NUP42 protein, S cerevisiae; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; D012331:RNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; D054321:rev Gene Products, Human Immunodeficiency Virus