This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sydorskyy, Y.
Right arrow Articles by Aitchison, J. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sydorskyy, Y.
Right arrow Articles by Aitchison, J. D.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, March 2003, p. 2042-2054, Vol. 23, No. 6
0270-7306/03/$08.00+0     DOI: 10.1128/MCB.23.6.2042-2054.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Intersection of the Kap123p-Mediated Nuclear Import and Ribosome Export Pathways

Y. Sydorskyy,1,2 D. J. Dilworth,1,2 E. C. Yi,1 D. R. Goodlett,1 R. W. Wozniak,2 and J. D. Aitchison1,2*

Institute for Systems Biology, Seattle, Washington 98105,1 Department of Cell Biology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada2

Received 12 July 2002/ Returned for modification 28 August 2002/ Accepted 13 December 2002

Kap123p is a yeast ß-karyopherin that imports ribosomal proteins into the nucleus prior to their assembly into preribosomal particles. Surprisingly, Kap123p is not essential for growth, under normal conditions. To further explore the role of Kap123p in nucleocytoplasmic transport and ribosome biogenesis, we performed a synthetic fitness screen designed to identify genes that interact with KAP123. Through this analysis we have identified three other karyopherins, Pse1p/Kap121p, Sxm1p/Kap108p, and Nmd5p/Kap119p. We propose that, in the absence of Kap123p, these karyopherins are able to supplant Kap123p's role in import. In addition to the karyopherins, we identified Rai1p, a protein previously implicated in rRNA processing. Rai1p is also not essential, but deletion of the RAI1 gene is deleterious to cell growth and causes defects in rRNA processing, which leads to an imbalance of the 60S/40S ratio and the accumulation of halfmers, 40S subunits assembled on polysomes that are unable to form functional ribosomes. Rai1p localizes predominantly to the nucleus, where it physically interacts with Rat1p and pre-60S ribosomal subunits. Analysis of the rai1/kap123 double mutant strain suggests that the observed genetic interaction results from an inability to efficiently export pre-60S subunits from the nucleus, which arises from a combination of compromised Kap123p-mediated nuclear import of the essential 60S ribosomal subunit export factor, Nmd3p, and a {Delta}RAI1-induced decrease in the overall biogenesis efficiency.


* Corresponding author. Mailing address: Institute for Systems Biology, 1441 N 34th St., Seattle, WA 98103. Phone: (206) 732-1344. Fax: (206) 732-1299. E-mail: jaitchison{at}systemsbiology.org.


Molecular and Cellular Biology, March 2003, p. 2042-2054, Vol. 23, No. 6
0022-538X/03/$08.00+0     DOI: 10.1128/MCB.23.6.2042-2054.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Chang, Y. C., Ingavale, S. S., Bien, C., Espenshade, P., Kwon-Chung, K. J. (2009). Conservation of the Sterol Regulatory Element-Binding Protein Pathway and Its Pathobiological Importance in Cryptococcus neoformans. Eukaryot Cell 8: 1770-1779 [Abstract] [Full Text]  
  • Hedges, J., Chen, Y.-I, West, M., Bussiere, C., Johnson, A. W. (2006). Mapping the Functional Domains of Yeast NMD3, the Nuclear Export Adapter for the 60 S Ribosomal Subunit. J. Biol. Chem. 281: 36579-36587 [Abstract] [Full Text]  
  • Timney, B. L., Tetenbaum-Novatt, J., Agate, D. S., Williams, R., Zhang, W., Chait, B. T., Rout, M. P. (2006). Simple kinetic relationships and nonspecific competition govern nuclear import rates in vivo. JCB 175: 579-593 [Abstract] [Full Text]  
  • Seiser, R. M., Sundberg, A. E., Wollam, B. J., Zobel-Thropp, P., Baldwin, K., Spector, M. D., Lycan, D. E. (2006). Ltv1 Is Required for Efficient Nuclear Export of the Ribosomal Small Subunit in Saccharomyces cerevisiae. Genetics 174: 679-691 [Abstract] [Full Text]  
  • Lebreton, A., Saveanu, C., Decourty, L., Rain, J.-C., Jacquier, A., Fromont-Racine, M. (2006). A functional network involved in the recycling of nucleocytoplasmic pre-60S factors. JCB 173: 349-360 [Abstract] [Full Text]  
  • Bakhrat, A., Baranes, K., Krichevsky, O., Rom, I., Schlenstedt, G., Pietrokovski, S., Raveh, D. (2006). Nuclear Import of Ho Endonuclease Utilizes Two Nuclear Localization Signals and Four Importins of the Ribosomal Import System. J. Biol. Chem. 281: 12218-12226 [Abstract] [Full Text]  
  • Hodges, J. L., Leslie, J. H., Mosammaparast, N., Guo, Y., Shabanowitz, J., Hunt, D. F., Pemberton, L. F. (2005). Nuclear Import of TFIIB Is Mediated by Kap114p, a Karyopherin with Multiple Cargo-binding Domains. Mol. Biol. Cell 16: 3200-3210 [Abstract] [Full Text]  
  • BRUNE, C., MUNCHEL, S. E., FISCHER, N., PODTELEJNIKOV, A. V., WEIS, K. (2005). Yeast poly(A)-binding protein Pab1 shuttles between the nucleus and the cytoplasm and functions in mRNA export. RNA 11: 517-531 [Abstract] [Full Text]  
  • Leslie, D. M., Zhang, W., Timney, B. L., Chait, B. T., Rout, M. P., Wozniak, R. W., Aitchison, J. D. (2004). Characterization of Karyopherin Cargoes Reveals Unique Mechanisms of Kap121p-Mediated Nuclear Import. Mol. Cell. Biol. 24: 8487-8503 [Abstract] [Full Text]