title: Identification of proteins associating with poly(A)-binding-protein mRNA.
abstract: Synthesis of poly(A)-binding protein is regulated at the translational level. We have investigated the binding of proteins to this mRNA on the premise that the protein(s) of the mRNP complex may be involved in regulating the expression of the mRNA. We found the first 243 nucleotides of the 5' untranslated region to contain sequences essential for RNP formation. A large, single-stranded bulge structure encompassing stretches rich in adenine nucleotides and a potential stem-loop domain appear to be the primary sites for protein binding. Removal of the 243-nucleotide segment results in a drastic reduction in protein binding and a concomitant increase in translational efficiency in vitro. We suggest that proteins binding to this region, including poly(A)-binding protein itself, may be essential for regulating translation of this mRNA.
authors.affiliation: Department of Molecular Biology and Genetics, College of Biological Sciences, University of Guelph, Canada.
authors.forename: L C
authors.initials: LC
authors.lastname: Berger
authors.forename: J
authors.initials: J
authors.lastname: Bag
authors.forename: B H
authors.initials: BH
authors.lastname: Sells
mesh_terms: D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002474:Cell-Free System; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010957:Plasmids; D039102:Poly(A)-Binding Proteins; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D006163:Ribonuclease T1 / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D002352:Carrier Proteins; D039102:Poly(A)-Binding Proteins; D012333:RNA, Messenger; D006163:Ribonuclease T1