Autor: |
Dinman, J D, Wickner, R B |
Zdroj: |
The Journal of Virology; June 1992, Vol. 66 Issue: 6 p3669-3676, 8p |
Abstrakt: |
About 1.9% of ribosomes translating the gag open reading frame of the yeast L-A double-stranded RNA virus positive strand undergo a -1 frameshift and continue translating in the pol open reading frame to make a 170-kDa gag-pol fusion protein. The importance of frameshifting efficiency for viral propagation was tested in a system where the M1 (killer toxin-encoding) satellite RNA is supported by a full-length L-A cDNA clone. Either increasing or decreasing the frameshift efficiency more than twofold by alterations in the slippery site disrupted viral propagation. A threefold increase caused by a chromosomal mutation, hsh1 (high shifter), had the same effect. Substituting a +1 ribosomal frameshift site from Ty1 with the correct efficiency also allowed support of M1 propagation. The normal -1 frameshift efficiency is similar to the observed molar ratio in viral particles of the 170-kDa gag-pol protein to the 70-kDa gag gene product, the major coat protein. The results are interpreted in terms of a packaging model for L-A. |
Databáze: |
Supplemental Index |
Externí odkaz: |
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