title: A protein.protein interaction platform involved in recruitment of GLD-3 to the FBF.fem-3 mRNA complex.
abstract: The Pumilio and FBF (PUF) family of RNA-binding proteins interacts with protein partners to post-transcriptionally regulate mRNAs in eukaryotes. The interaction between PUF family member fem-3 binding factor (FBF) and germline development defective-3 (GLD-3) protein promotes spermatogenesis in Caenorhabditis elegans by increasing expression of the fem-3 mRNA. Defined here in these studies is the molecular basis for this critical interaction. A 10-amino-acid region within GLD-3 is required for FBF binding, while a 7-amino-acid loop in FBF between PUF repeats 7 and 8 is necessary for GLD-3 binding. These short sequences are conserved, as other FBF-binding proteins bear sequences similar to those in GLD-3 and other C. elegans PUF proteins contain sequences similar to those in FBF. The FBF-binding region of GLD-3 forms a ternary complex with FBF on the point mutation element (PME) in the fem-3 3' untranslated region, and formation of this GLD-3⋅FBF complex does not impact the RNA-binding activity of FBF. These data raise the possibility of alternative models involving the formation of a GLD-3⋅FBF⋅RNA complex in the regulation of germline mRNAs.
authors.affiliation: Department of Molecular Biology, Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Joann
authors.initials: J
authors.lastname: Wu
authors.forename: Zachary T
authors.initials: ZT
authors.lastname: Campbell
authors.forename: Elena
authors.initials: E
authors.lastname: Menichelli
authors.forename: Marvin
authors.initials: M
authors.lastname: Wickens
authors.forename: James R
authors.initials: JR
authors.lastname: Williamson
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D024202:Electrophoretic Mobility Shift Assay; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods; D017434:Protein Structure, Tertiary; D018510:RNA, Helminth / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques
chemical_list: D000596:Amino Acids; D029742:Caenorhabditis elegans Proteins; C469731:GLD-3 protein, C elegans; D018510:RNA, Helminth; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C075059:fem-3 protein, C elegans; C109286:fem-3-binding protein, C elegans