Interaction with host SGS3 is required for suppression of RNA silencing by tomato yellow leaf curl virus V2 protein.
The V2 protein of tomato yellow leaf curl geminivirus (TYLCV) functions as an RNA-silencing suppressor that counteracts the innate immune response of the host plant. The host-cell target of V2, however, remains unknown. Here we show that V2 interacts directly with SlSGS3, the tomato homolog of the Arabidopsis SGS3 protein (AtSGS3), which is known to be involved in the RNA-silencing pathway. SlSGS3 genetically complemented an AtSGS3 mutation and restored RNA silencing, indicating that SlSGS3 is indeed a functional homolog of AtSGS3. A point mutant of V2 that is unable to bind SlSGS3 also lost its ability to suppress RNA silencing, suggesting a correlation between the V2-SlSGS3 interaction in planta and the suppressor activity of V2.
Glick
Efrat
E
Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, P. O. Box 6, Bet Dagan 50250, Israel.
Zrachya
Avi
A
Levy
Yael
Y
Mett
Anahit
A
Gidoni
David
D
Belausov
Eduard
E
Citovsky
Vitaly
V
Gafni
Yedidya
Y
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000378:metabolism; D053839:Begomovirus / Q000378:metabolism*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D005816:Genetic Complementation Test; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000737:chemistry
D014764:Viral Proteins