Protein Binding And Rna Binding Properties Of Rna Binding Proteins Fbf And Rbm39 PDF Download

Post-transcriptional regulation of gene expression is critical in the development, physiology, and reproduction of multicellular organisms. Large dynamic multi-protein complexes formed through extensive protein*protein and protein*RNA interactions control mRNA processing, splicing, nuclear transport, localization, stability, and translation. However, despite the biological importance of these regulatory complexes, there is sparse molecular information describing the interactions involved in their assembly. In these studies, two categories of RNA-binding proteins that act as foundations for these complexes are examined: the Pu milio and F[barbelow]BF (PUF) proteins and R[barbelow]NA r[barbelow]ecognition m[barbelow]otif (RRM) domain-containing proteins. While there is a wealth of knowledge for PUF protein interactions with RNA, there is limited information describing the equally essential interactions between PUF proteins and their protein binding partners. Defined in these studies are the molecular bases for the developmentally essential interactions between Caenorhabditis elegans PUF protein f[barbelow]em-3 b[barbelow]inding f[barbelow]actor (FBF) and the two protein binding partners: g[barbelow]erml[barbelow]ine d[barbelow]evelopment defective-3[barbelow] (GLD-3) and c[barbelow]ytoplasmic p[barbelow]olyadenylation element b[barbelow]inding-1 (CPB-1). Short specific sequences in unstructured regions of the GLD-3 and CPB-1 proteins are critical for interaction with FBF, while a loop connecting PUF repeats R7 and R8 in FBF is essential for association with both GLD-3 and CPB-1. The PUF protein*binding partner complex FBF*GLD-3 is capable of forming a stable complex on RNA FBF regulatory elements in the 3' u[barbelow]nt[barbelow]ranslated r[barbelow]egions (UTR) of specific germline developmental mRNAs, and may control their expression through several proposed mechanisms. Although the RRM domains that characterize RRM-containing proteins adopt the same vary greatly in: amino acid sequence; DNA, RNA, and protein-binding abilities; and mode of interaction with these biological molecules. These studies potentially identify the first member of a unique class of RRMs that bind to RNA in a manner similar to RRMs that interact with proteins. These studies characterizing the protein- and RNA-binding properties of these RNA-binding proteins provide insight into the biologically essential molecular complexes involved in post-transcriptional gene regulation.