title: Ran-binding protein 3 phosphorylation links the Ras and PI3-kinase pathways to nucleocytoplasmic transport.
abstract: The major participants of the Ras/ERK and PI3-kinase (PI3K) pathways are well characterized. The cellular response to activation of these pathways, however, can vary dramatically. How differences in signal strength, timing, spatial location, and cellular context promote specific cell-fate decisions remains unclear. Nuclear transport processes can have a major impact on the determination of cell fate; however, little is known regarding how nuclear transport is regulated by or regulates these pathways. Here we show that RSK and Akt, which are activated downstream of Ras/ERK and PI3K, respectively, modulate the Ran gradient and nuclear transport by interacting with, phosphorylating, and regulating Ran-binding protein 3 (RanBP3) function. Our findings highlight an important link between two major cell-fate determinants: nuclear transport and the Ras/ERK/RSK and PI3K/Akt signaling pathways.
authors.affiliation: Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Sang-Oh
authors.initials: SO
authors.lastname: Yoon
authors.forename: Sejeong
authors.initials: S
authors.lastname: Shin
authors.forename: Yuzhen
authors.initials: Y
authors.lastname: Liu
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Ballif
authors.forename: Michele S
authors.initials: MS
authors.lastname: Woo
authors.forename: Steven P
authors.initials: SP
authors.lastname: Gygi
authors.forename: John
authors.initials: J
authors.lastname: Blenis
mesh_terms: D021581:Active Transport, Cell Nucleus; D002467:Cell Nucleus / Q000378:metabolism*; D004789:Enzyme Activation; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D029543:Nucleocytoplasmic Transport Proteins / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000378:metabolism; D015398:Signal Transduction; D013379:Substrate Specificity; D018631:ras Proteins / Q000378:metabolism*
chemical_list: D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; C112820:RANBP3 protein, human; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D038744:Ribosomal Protein S6 Kinases, 90-kDa; D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins