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The mRNA export factor Npl3 mediates the nuclear export of large ribosomal subunits.

ABSTRACT: The nuclear export of large ribonucleoparticles is complex and requires specific transport factors. Messenger RNAs are exported through the RNA-binding protein Npl3 and the interacting export receptor Mex67. Export of large ribosomal subunits also requires Mex67; however, in this case, Mex67 binds directly to the 5S ribosomal RNA (rRNA) and does not require the Npl3 adaptor. Here, we have discovered a new function of Npl3 in mediating the export of pre-60S ribosomal subunit independently of Mex67. Npl3 interacts with the 25S rRNA, ribosomal and ribosome-associated proteins, as well as with the nuclear pore complex. Mutations in NPL3 lead to export defects of the large subunit and genetic interactions with other pre-60S export factors.

SUBMITTER: Hackmann A

PROVIDER: S-EPMC3185341 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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The mRNA export factor Npl3 mediates the nuclear export of large ribosomal subunits.

Hackmann Alexandra A Gross Thomas T Baierlein Claudia C Krebber Heike H

EMBO reports 20110930 10

The nuclear export of large ribonucleoparticles is complex and requires specific transport factors. Messenger RNAs are exported through the RNA-binding protein Npl3 and the interacting export receptor Mex67. Export of large ribosomal subunits also requires Mex67; however, in this case, Mex67 binds directly to the 5S ribosomal RNA (rRNA) and does not require the Npl3 adaptor. Here, we have discovered a new function of Npl3 in mediating the export of pre-60S ribosomal subunit independently of Mex6 ...[more]

PMID: 21852791

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