Identification and molecular cloning of a human selenocysteine insertion sequence-binding protein. A bifunctional role for DNA-binding protein B
Document Type
Journal ArticlePublication Date
1998-04-16Keywords
Amino Acid SequenceAnimals
*CCAAT-Enhancer-Binding Proteins
Cell Line
Cloning, Molecular
DNA-Binding Proteins
Gene Products, tat
Glutathione Peroxidase
Humans
Iodide Peroxidase
Molecular Sequence Data
NFI Transcription Factors
Nuclear Proteins
Protein Biosynthesis
*Proteins
RNA-Binding Proteins
Recombinant Proteins
Selenocysteine
Selenoproteins
Sequence Analysis
Sequence Analysis, DNA
Sequence Homology, Amino Acid
*Transcription Factors
Y-Box-Binding Protein 1
Life Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Prokaryotic and eukaryotic cells incorporate the unusual amino acid selenocysteine at a UGA codon, which conventionally serves as a termination signal. Translation of eukaryotic selenoprotein mRNA requires a nucleotide selenocysteine insertion sequence in the 3'-untranslated region. We report the molecular cloning of the binding protein that recognizes the selenocysteine insertion sequence element in human cellular glutathione peroxidase gene (GPX1) transcripts and its identification as DNA-binding protein B, a member of the EFIA/dbpB/YB-1 family. The predicted amino acid sequence contains four arginine-rich RNA-binding motifs, and one segment shows strong homology to the human immunodeficiency virus Tat domain. Recombinant DNA-binding protein B binds the selenocysteine insertion sequence elements from the GPX1 and type I iodothyronine 5'-deiodinase genes in RNA electrophoretic mobility shift assays and competes with endogenous GPX1 selenocysteine insertion sequence binding activity in COS-1 cytosol extracts. Addition of antibody to DNA-binding protein B to COS-1 electromobility shift assays produces a slowly migrating "supershift" band. The molecular cloning and identification of DNA-binding protein B as the first eukaryotic selenocysteine insertion sequence-binding protein opens the way to the elucidation of the entire complex necessary for the alternative reading of the genetic code that permits translation of selenoproteins.Source
J Biol Chem. 1998 Mar 6;273(10):5443-6.
DOI
10.1074/jbc.273.10.5443Permanent Link to this Item
http://hdl.handle.net/20.500.14038/42432PubMed ID
9488664Related Resources
ae974a485f413a2113503eed53cd6c53
10.1074/jbc.273.10.5443
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