Genetic reprogramming by retroviruses: enhanced suppression of translational termination.
Viruses often exploit or subvert host machinery for their own purposes during replication. A search for proteins interacting with the murine leukemia virus reverse transcriptase (RT) recently provided a new example of such exploitation. RT was found to bind the eukaryotic translational release factor 1 (eRF1), the protein that recognizes stop codons and, in complex with eRF3, causes termination and polypeptide release from the ribosome. RT is derived from a large Gag-Pol polyprotein, and its synthesis requires a translational readthrough, a suppression of termination, at a stop codon at the end of the gag gene. The binding of eRF1 by RT was found to inhibit eRF1 action, enhance the efficiency of readthrough, and thus cause higher levels of RT synthesis. The observations suggest that retroviruses manipulate the translational machinery in sophisticated ways to fine-tune their own gene expression.
Goff
Stephen P
SP
Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA. goff@cancercenter.columbia.edu
D018388:Codon, Terminator / Q000235:genetics; D015685:Fusion Proteins, gag-pol / Q000378:metabolism; D010443:Peptide Chain Termination, Translational / Q000235:genetics / Q000502:physiology; D010454:Peptide Termination Factors / Q000235:genetics / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000235:genetics / Q000502:physiology; D012343:RNA, Transfer / Q000378:metabolism; D012194:RNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism*; D012190:Retroviridae / Q000235:genetics* / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism; D013489:Suppression, Genetic / Q000235:genetics / Q000502:physiology; D013728:Terminator Regions, Genetic / Q000235:genetics / Q000502:physiology
D018388:Codon, Terminator; D015685:Fusion Proteins, gag-pol; D010454:Peptide Termination Factors; D012343:RNA, Transfer; D012194:RNA-Directed DNA Polymerase