title: Mechanochemical removal of ribosome biogenesis factors from nascent 60S ribosomal subunits.
abstract: The dynein-related AAA ATPase Rea1 is a preribosomal factor that triggers an unknown maturation step in 60S subunit biogenesis. Using electron microscopy, we show that Rea1's motor domain is docked to the pre-60S particle and its tail-like structure, harboring a metal ion-dependent adhesion site (MIDAS), protrudes from the preribosome. Typically, integrins utilize a MIDAS to bind extracellular ligands, an interaction that is strengthened under applied tensile force. Likewise, the Rea1 MIDAS binds the preribosomal factor Rsa4, which is located on the pre-60S subunit at a site that is contacted by the flexible Rea1 tail. The MIDAS-Rsa4 interaction is essential for ATP-dependent dissociation of a group of non-ribosomal factors from the pre-60S particle. Thus, Rea1 aligns with its interacting partners on the preribosome to effect a necessary step on the path to the export-competent 60S subunit.
authors.affiliation: Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Ulbrich
authors.forename: Meikel
authors.initials: M
authors.lastname: Diepholz
authors.forename: Jochen
authors.initials: J
authors.lastname: Bassler
authors.forename: Dieter
authors.initials: D
authors.lastname: Kressler
authors.forename: Brigitte
authors.initials: B
authors.lastname: Pertschy
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Galani
authors.forename: Bettina
authors.initials: B
authors.lastname: Böttcher
authors.forename: Ed
authors.initials: E
authors.lastname: Hurt
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases / Q000378:metabolism* / Q000648:ultrastructure; D000255:Adenosine Triphosphate / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D054683:Ribosome Subunits, Large, Eukaryotic / Q000378:metabolism* / Q000648:ultrastructure; D012441:Saccharomyces cerevisiae / Q000378:metabolism* / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: C496539:Rix1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C496538:MDN1 protein, S cerevisiae; D000074183:ATPases Associated with Diverse Cellular Activities