Previous Article | Next Article ![]()
Molecular and Cellular Biology, November 1998, p. 6374-6386, Vol. 18, No. 11
Biochemie-Zentrum
Heidelberg1 and
Abteilung Molekulare
Biologie der Mitose, Deutsches
Krebsforschungszentrum,2 69120 Heidelberg,
Germany
Received 30 March 1998/Returned for modification 18 May
1998/Accepted 5 August 1998
Saccharomyces cerevisiae Los1p, which is genetically
linked to the nuclear pore protein Nsp1p and several tRNA biogenesis factors, was recently grouped into the family of
importin/karyopherin-
0270-7306/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Yeast Los1p Has Properties of an Exportin-Like
Nucleocytoplasmic Transport Factor for tRNA
-like proteins on the basis of its sequence
similarity. In a two-hybrid screen, we identified Nup2p as a
nucleoporin interacting with Los1p. Subsequent purification of Los1p
from yeast demonstrates its physical association not only with Nup2p
but also with Nsp1p. By the use of the Gsp1p-G21V mutant, Los1p was
shown to preferentially bind to the GTP-bound form of yeast Ran.
Furthermore, overexpression of full-length or N-terminally truncated
Los1p was shown to have dominant-negative effects on cell growth and
different nuclear export pathways. Finally, Los1p could interact with
Gsp1p-GTP, but only in the presence of tRNA, as revealed in an indirect
in vitro binding assay. These data confirm the homology between Los1p and the recently identified human exportin for tRNA and reinforce the
possibility of a role for Los1p in nuclear export of tRNA in yeast.
*
Corresponding author. Mailing address:
Biochemie-Zentrum Heidelberg (BZH), Im Neuenheimer Feld 328, D-69120
Heidelberg, Germany. Phone: 49-6221-546757. Fax: 49-6221-544369. E-mail
for E.H.: cg5{at}ix.urz.uni-heidelberg.de. E-mail for G.S.: cg2{at}ix.urz.uni-heidelberg.de.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|