The Gag domain of the Gag-Pol fusion protein directs incorporation into the L-A double-stranded RNA viral particles in Saccharomyces cerevisiae.
The L-A double-stranded RNA virus of yeast encodes its major coat protein, Gag, and a Gag-Pol fusion protein made by a -1 ribosomal frameshift, a coding strategy used by many retroviruses. We find that cells expressing only Gag from one plasmid and only Gag-Pol (in frame) from a separate plasmid can support the propagation of M1 double-stranded RNA, encoding the killer toxin. We use this system to separately investigate the functions of Gag and the Gag part of Gag-Pol. L-A contains two fusion protein molecules per particle, and although N-terminal acetylation of Gag is essential for viral assembly, it is completely dispensable for function of Gag-Pol. In general, the requirements on Gag for viral assembly and propagation are more stringent than on the Gag part of Gag-Pol. Finally, we directly show that it is Gag that instructs the incorporation of Gag-Pol into the viral particles.
Ribas
J C
JC
Laboratory of Biochemistry and Genetics, NIDDK, National Institutes of Health, Bethesda, Maryland 20892-0830, USA.
Wickner
R B
RB
D015685:Fusion Proteins, gag-pol / Q000378:metabolism*; D015683:Gene Products, gag / Q000378:metabolism*; D055646:Killer Factors, Yeast; D010957:Plasmids; D014176:Protein Biosynthesis; D011506:Proteins; D012328:RNA Viruses / Q000235:genetics / Q000502:physiology*; D012330:RNA, Double-Stranded / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000821:virology*; D017384:Sequence Deletion; D014779:Virus Replication
D015685:Fusion Proteins, gag-pol; D015683:Gene Products, gag; D055646:Killer Factors, Yeast; D011506:Proteins; D012330:RNA, Double-Stranded; D012367:RNA, Viral; D011994:Recombinant Proteins