Specific binding of host cell proteins to the 3'-terminal stem-loop structure of rubella virus negative-strand RNA.
At the 5' end of the rubella virus genomic RNA, there are sequences that can form a potentially stable stem-loop (SL) structure. The complementary negative-strand equivalent of the 5'-end SL structure of positive-strand rubella virus RNA [5' (+) SL structure] is thought to serve as a promoter for the initiation of positive-strand synthesis. We screened the negative-strand equivalent of the 5' (+) SL structure (64 nucleotides) and the adjacent region of the negative-strand RNA for their ability to bind to host cell proteins. Specific binding to the 64-nucleotide-long potential SL structure of three cytosolic proteins with relative molecular masses of 97, 79, and 56 kDa was observed by UV-induced covalent cross-linking. There was a significant increase in the binding of the 97-kDa protein from cells upon infection with rubella virus. Altering the SL structure by deleting sequences in either one of the two potential loops abolished the binding interaction. The 56-kDa protein also appeared to bind specifically to an SL derived from the 3' end of positive-strand RNA. The 3'-terminal structure of rubella virus negative-strand RNA shared the same protein-binding activity with similar structures in alphaviruses, such as Sindbis virus and eastern equine encephalitis virus. A possible role for the host proteins in the replication of rubella virus and alphaviruses is discussed.
Nakhasi
H L
HL
Division of Biochemistry and Biophysics, CBER, Food and Drug Administration, Bethesda, Maryland 20892.
Cao
X Q
XQ
Rouault
T A
TA
Liu
T Y
TY
D000818:Animals; D001483:Base Sequence; D008961:Models, Structural; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016297:Mutagenesis, Site-Directed; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides; D011485:Protein Binding; D012367:RNA, Viral / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D012412:Rubella virus / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D012845:Sindbis Virus / Q000235:genetics; D014158:Transcription, Genetic; D014709:Vero Cells
D009838:Oligodeoxyribonucleotides; D012367:RNA, Viral