title: RRM domain of human RBM7: purification, crystallization and structure determination.
abstract: RNA decay is an important process that is essential for controlling the abundance, quality and maturation of transcripts. In eukaryotes, RNA decay in the 3'-5' direction is carried out by the exosome, an RNA-degradation machine that is conserved from yeast to humans. A range of cofactors stimulate the enzymatic activity of the exosome and serve as adapters for the many RNA substrates. In human cells, the exosome associates with the heterotrimeric nuclear exosome targeting (NEXT) complex consisting of the DExH-box helicase hMTR4, the zinc-finger protein hZCCHC8 and the RRM-type protein hRBM7. Here, the 2.5 Å resolution crystal structure of the RRM domain of human RBM7 is reported. Molecular replacement using a previously determined solution structure of RBM7 was unsuccessful. Instead, RBM8 and CBP20 RRM-domain crystal structures were used to successfully determine the RBM7 structure by molecular replacement. The structure reveals a ring-shaped pentameric assembly, which is most likely a consequence of crystal packing.
authors.affiliation: Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Sofos
authors.affiliation: Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
authors.forename: Mikael B L
authors.initials: MB
authors.lastname: Winkler
authors.affiliation: Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10c, DK-8000 Aarhus C, Denmark.
authors.forename: Ditlev E
authors.initials: DE
authors.lastname: Brodersen
mesh_terms: D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D006801:Humans; D011487:Protein Conformation; D000072417:Protein Domains; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
chemical_list: C000596172:RBM7 protein, human; D016601:RNA-Binding Proteins
keywords: NEXT complex; RNA degradation; RRM domain; X-ray crystallography; human