Previous Article | Next Article ![]()
Molecular and Cellular Biology, March 2009, p. 1487-1497, Vol. 29, No. 6
0270-7306/09/$08.00+0 doi:10.1128/MCB.01519-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.
,
Alexander Strehblow,1,
Andreas Taschner,1
Sandy Schopoff,1
Pawel Pasierbek,2 and
Michael F. Jantsch1*
Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohr Gasse 1, A-1030 Vienna, Austria,1 Research Institute of Molecular Pathology, Dr. Bohr Gasse 7, A-1030 Vienna, Austria2
Received 30 September 2008/ Returned for modification 22 October 2008/ Accepted 23 December 2008
Double-stranded RNA (dsRNA)-binding proteins interact with substrate RNAs via dsRNA-binding domains (dsRBDs). Several proteins harboring these domains exhibit nucleocytoplasmic shuttling and possibly remain associated with their substrate RNAs bound in the nucleus during nuclear export. In the human RNA-editing enzyme ADAR1-c, the nuclear localization signal overlaps the third dsRBD, while the corresponding import factor is unknown. The protein also lacks a clear nuclear export signal but shuttles between the nucleus and the cytoplasm. Here we identify transportin-1 as the import receptor for ADAR1. Interestingly, dsRNA binding interferes with transportin-1 binding. At the same time, each of the dsRBDs in ADAR1 interacts with the export factor exportin-5. RNA binding stimulates this interaction but is not a prerequisite. Thus, our data demonstrate a role for some dsRBDs as RNA-sensitive nucleocytoplasmic transport signals. dsRBD3 in ADAR1 can mediate nuclear import, while interaction of all dsRBDs might control nuclear export. This finding may have implications for other proteins containing dsRBDs and suggests a selective nuclear export mechanism for substrates interacting with these proteins.
Published ahead of print on 5 January 2009.
Supplemental material for this article may be found at http://mcb.asm.org/.
J.F. and A.S. contributed equally to this study.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»