title: Rna14-Rna15 assembly mediates the RNA-binding capability of Saccharomyces cerevisiae cleavage factor IA.
abstract: The Rna14-Rna15 complex is a core component of the cleavage factor IA RNA-processing complex from Saccharomyces cerevisiae. To understand the assembly and RNA-binding properties, we have isolated and characterized the Rna14-Rna15 complex using a combination of biochemical and biophysical methods. Analysis of the purified complex, using transmission electron microscopy, reveals that the two proteins assemble into a kinked rod-shaped structure and that these rods are able to further self-associate. Analytical ultracentrifugation reveals that Rna14 mediates this association and facilitates assembly of an A2B2 tetramer (M(r) 230 000), where relatively compact Rna14-Rna15 heterodimers are in rapid equilibrium with tetramers that have a more extended shape. The Rna14-Rna15 complex, unlike the individual components, binds to an RNA oligonucleotide derived from the 3'-untranslated region of the S.cerevisiae GAL7 gene. Based on these structural and thermodynamic data, we propose that CFIA assembly regulates RNA-binding activity.
authors.affiliation: Division of Protein Structur, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK.
authors.forename: Christian G
authors.initials: CG
authors.lastname: Noble
authors.forename: Philip A
authors.initials: PA
authors.lastname: Walker
authors.forename: Lesley J
authors.initials: LJ
authors.lastname: Calder
authors.forename: Ian A
authors.initials: IA
authors.lastname: Taylor
mesh_terms: D046911:Macromolecular Substances; D008954:Models, Biological; D012331:RNA, Fungal / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism* / Q000648:ultrastructure; D039221:mRNA Cleavage and Polyadenylation Factors / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D046911:Macromolecular Substances; D012331:RNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; C512638:RNA14 protein, S cerevisiae; C512635:RNA15 protein, S cerevisiae