Interaction of 68-kDa TAR RNA-binding protein and other cellular proteins with prion protein-RNA stem-loop.
The RNA stem-loop structure of the trans-activating region TAR sequence of human immunodeficiency virus-1 mRNA is the binding site for a number of host cell proteins. A virtually identical set of proteins from HeLa nuclear extracts was found to bind to the predicted RNA hairpin element of prion protein (PrP) mRNA, as demonstrated in UV cross-linking/RNase protection and Northwestern assays. We show that the cellular TAR loop-binding protein, p68, is among those proteins which associate with PrP RNA. Competition experiments with various TAR RNA mutants revealed that binding of partially purified p68 to PrP RNA stem-loop occurs sequence-specifically. The 100-kDa 2-5A synthetase which is involved in the cellular antiviral defense was able to bind to PrP mRNA stem-loop in Northwestern blots with cytosolic proteins from HeLa cells treated with interferon. However, the PrP RNA failed to activate this enzyme in vitro, in contrast to TAR RNA.
Scheffer
U
U
Institut für Physiologische Chemie, Universität, Mainz, Germany.
Okamoto
T
T
Forrest
J M
JM
Rytik
P G
PG
Müller
W E
WE
Schröder
H C
HC
D015088:2',5'-Oligoadenylate Synthetase / Q000378:metabolism; D001483:Base Sequence; D001667:Binding, Competitive / Q000235:genetics; D015152:Blotting, Northern; D015153:Blotting, Western; D016325:HIV Long Terminal Repeat / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008214:Lymphocytes / Q000737:chemistry / Q000201:enzymology / Q000382:microbiology; D008969:Molecular Sequence Data; D016296:Mutagenesis / Q000502:physiology; D009690:Nucleic Acid Conformation; D011328:Prions / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*
D011328:Prions; D016601:RNA-Binding Proteins; D011956:Receptors, Cell Surface; D015088:2',5'-Oligoadenylate Synthetase