Suppressor of RNA silencing encoded by Tomato yellow leaf curl virus-Israel.
The Israeli isolate of Tomato yellow leaf curl geminivirus (TYLCV-Is) is a major tomato pathogen, causing extensive crop losses both in the New and Old World. Surprisingly, however, little is known about the molecular mechanisms of TYLCV-Is interactions with tomato cells. Here, we have identified a TYLCV-Is protein, V2, which acts as a suppressor of RNA silencing and which is unrelated to presently known viral suppressors. Specifically, V2, but not other proteins of TYLCV-Is, inhibited RNA silencing of a reporter transgene, GFP. This inhibition elevated the cellular levels of the GFP transcript and the GFP protein, but it had no apparent effect on the accumulation of GFP-specific short interfering RNAs (siRNAs), suggesting that TYLCV-Is V2 targets a step in the RNA silencing pathway which is subsequent to the Dicer-mediated cleavage of dsRNA. Visualization of the sub-cellular localization of TYLCV-Is V2 in plant protoplasts and tissues showed that this protein is associated with cytoplasmic strands and inclusion bodies in the cortical regions of the cell.
Zrachya
Avi
A
Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel.
Glick
Efrat
E
Levy
Yael
Y
Arazi
Tzahi
T
Citovsky
Vitaly
V
Gafni
Yedidya
Y
D053839:Begomovirus / Q000235:genetics / Q000472:pathogenicity*; D015153:Blotting, Western; D003593:Cytoplasm / Q000737:chemistry; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D002479:Inclusion Bodies / Q000737:chemistry; D018551:Solanum lycopersicum / Q000821:virology*; D018613:Microscopy, Confocal; D011523:Protoplasts / Q000737:chemistry; D034622:RNA Interference; D012333:RNA, Messenger / Q000032:analysis; D034741:RNA, Small Interfering / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014764:Viral Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins