Unique Motif for Nucleolar Retention and Nuclear Export Regulated by Phosphorylation |
| |
Authors: | Frdric Catez Monique Erard Nathalie Schaerer-Uthurralt Karine Kindbeiter Jean-Jacques Madjar and Jean-Jacques Diaz |
| |
Institution: | INSERM U369, Faculté de Médecine Lyon-René Théophile Hyacinthe Laennec, 69372 Lyon Cedex 08, France. |
| |
Abstract: | By microinjecting purified glutathione S-transferase linked to all or parts of herpes simplex virus type 1 US11 protein into either the nucleus or the cytoplasm, we have demonstrated that this nucleolar protein exhibits a new type of localization signal controlling both retention in nucleoli and export to the cytoplasm. Saturated mutagenesis combined with computer modeling allowed us to draw the fine-structure map of this domain, revealing a new proline-rich motif harboring both activities, which are temperature dependent and regulated by phosphorylation. Finally, crossing the nuclear pore complex from the cytoplasm to the nucleus is an energy-dependent process for US11 protein, while getting to nucleoli through the nucleoplasm is energy independent. |
| |
Keywords: | |
|
|