MCB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 Xu, C.
Right arrow Articles by Henry, M. F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Xu, C.
Right arrow Articles by Henry, M. F.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, December 2004, p. 10742-10756, Vol. 24, No. 24
0270-7306/04/$08.00+0     DOI: 10.1128/MCB.24.24.10742-10756.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Nuclear Export of hnRNP Hrp1p and Nuclear Export of hnRNP Npl3p Are Linked and Influenced by the Methylation State of Npl3p

Chong Xu and Michael F. Henry*

Department of Molecular Biology, University of Medicine and Dentistry New Jersey-School of Osteopathic Medicine, Stratford, New Jersey

Received 8 July 2004/ Returned for modification 12 August 2004/ Accepted 7 September 2004

Eukaryotic mRNA processing and export are mediated by a series of complexes composed of heterogeneous nuclear ribonucleoproteins (hnRNPs). Many of these hnRNPs are methylated at arginine residues within their RGG domains. Although cellular arginine methylation is required for the efficient nuclear export of several hnRNPs, its role in this process is unknown. To address this question, we replaced the methylated RGG tripeptides of two hnRNPs, Npl3p and Hrp1p, with KGG. We found that these substitutions specifically abolish their methylation but have different effects on their nuclear export activity. Although the efficient export of Hrp1p requires cellular methyltransferase activity, the modification of Hrp1p itself is dispensable. In contrast, we found that Npl3 arginine methylation not only facilitates its own export but also is required for Hrp1p to efficiently exit the nucleus. Consistent with this observation, we found that Npl3p and Hrp1p exist in a ribonucleoprotein complex. We provide the first evidence that the arginine methylation of a particular protein directly affects its activity. Efficient export does not require methylation per se, but unmethylated arginine residues lead to retention of hnRNPs. Thus, arginine methylation serves to mask the Npl3p RGG domain for efficient ribonucleoprotein export.

* Corresponding author. Mailing address: Department of Molecular Biology, UMNDJ-SOM, 2 Medical Center Dr., Stratford, NJ 08084. Phone: (856) 566-6970. Fax: (856) 566-6291. E-mail: henrymf{at}umdnj.edu.

Molecular and Cellular Biology, December 2004, p. 10742-10756, Vol. 24, No. 24
0022-538X/04/$08.00+0     DOI: 10.1128/MCB.24.24.10742-10756.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 2004 by the American Society for Microbiology. All rights reserved.