title: The structure of Rpf2-Rrs1 explains its role in ribosome biogenesis.
abstract: The assembly of eukaryotic ribosomes is a hierarchical process involving about 200 biogenesis factors and a series of remodeling steps. The 5S RNP consisting of the 5S rRNA, RpL5 and RpL11 is recruited at an early stage, but has to rearrange during maturation of the pre-60S ribosomal subunit. Rpf2 and Rrs1 have been implicated in 5S RNP biogenesis, but their precise role was unclear. Here, we present the crystal structure of the Rpf2-Rrs1 complex from Aspergillus nidulans at 1.5 Å resolution and describe it as Brix domain of Rpf2 completed by Rrs1 to form two anticodon-binding domains with functionally important tails. Fitting the X-ray structure into the cryo-EM density of a previously described pre-60S particle correlates with biochemical data. The heterodimer forms specific contacts with the 5S rRNA, RpL5 and the biogenesis factor Rsa4. The flexible protein tails of Rpf2-Rrs1 localize to the central protuberance. Two helices in the Rrs1 C-terminal tail occupy a strategic position to block the rotation of 25S rRNA and the 5S RNP. Our data provide a structural model for 5S RNP recruitment to the pre-60S particle and explain why removal of Rpf2-Rrs1 is necessary for rearrangements to drive 60S maturation.
authors.affiliation: Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany.
authors.forename: Satyavati
authors.initials: S
authors.lastname: Kharde
authors.affiliation: Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany.
authors.forename: Fabiola R
authors.initials: FR
authors.lastname: Calviño
authors.affiliation: Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Gumiero
authors.affiliation: Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany.
authors.forename: Klemens
authors.initials: K
authors.lastname: Wild
authors.affiliation: Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany irmi.sinning@bzh.uni-heidelberg.de.
authors.forename: Irmgard
authors.initials: I
authors.lastname: Sinning
mesh_terms: D001233:Aspergillus nidulans; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D008958:Models, Molecular; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012341:RNA, Ribosomal, 5S / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D012261:Ribonucleoproteins / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism; D054683:Ribosome Subunits, Large, Eukaryotic / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D012341:RNA, Ribosomal, 5S; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; D012269:Ribosomal Proteins; C027624:ribosomal protein L11