Abstract
The AAA(+)-ATPase Rea1 removes the ribosome biogenesis factor Rsa4 from pre-60S ribosomal subunits in the nucleoplasm to drive nuclear export of the subunit. To do this, Rea1 utilizes a MIDAS domain to bind a conserved motif in Rsa4. Here, we show that the Rea1 MIDAS domain binds another pre-60S factor, Ytm1, via a related motif. In vivo Rea1 contacts Ytm1 before it contacts Rsa4, and its interaction with Ytm1 coincides with the exit of early pre-60S particles from the nucleolus to the nucleoplasm. In vitro, Rea1's ATPase activity triggers removal of the conserved nucleolar Ytm1-Erb1-Nop7 subcomplex from isolated early pre-60S particle. We suggest that the Rea1 AAA(+)-ATPase functions at successive maturation steps to remove ribosomal factors at critical transition points, first driving the exit of early pre-60S particles from the nucleolus and then driving late pre-60S particles from the nucleus.
Copyright (c) 2010 Elsevier Inc. All rights reserved.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
ATPases Associated with Diverse Cellular Activities
-
Adenosine Triphosphatases / genetics
-
Adenosine Triphosphatases / metabolism*
-
Cell Nucleolus / metabolism
-
Microtubule-Associated Proteins / genetics
-
Microtubule-Associated Proteins / metabolism*
-
Nuclear Proteins / genetics
-
Nuclear Proteins / metabolism
-
Protein Binding
-
Protein Structure, Tertiary
-
Recombinant Fusion Proteins / genetics
-
Recombinant Fusion Proteins / metabolism
-
Ribosomal Proteins / genetics
-
Ribosomal Proteins / metabolism*
-
Ribosome Subunits, Large, Eukaryotic / genetics
-
Ribosome Subunits, Large, Eukaryotic / metabolism*
-
Saccharomyces cerevisiae / genetics
-
Saccharomyces cerevisiae / metabolism
-
Saccharomyces cerevisiae Proteins / genetics
-
Saccharomyces cerevisiae Proteins / metabolism*
-
Two-Hybrid System Techniques
Substances
-
Erb1 protein, S cerevisiae
-
Microtubule-Associated Proteins
-
NOP7 protein, S cerevisiae
-
Nuclear Proteins
-
Recombinant Fusion Proteins
-
Ribosomal Proteins
-
Rix1 protein, S cerevisiae
-
Rsa4 protein, S cerevisiae
-
Saccharomyces cerevisiae Proteins
-
Ytm1 protein, S cerevisiae
-
Adenosine Triphosphatases
-
MDN1 protein, S cerevisiae
-
ATPases Associated with Diverse Cellular Activities