title: Suppressors of RNA silencing encoded by tomato leaf curl betasatellites.
abstract: Virus encoded RNA-silencing suppressors (RSSs) are the key components evolved by the viruses to counter RNA-silencing defense of plants. Whitefly-transmitted begomoviruses infecting tomato crop code for five different proteins, ORF AC4, ORF AC2 and ORF AV2 in DNA-A component, ORF BV1 in DNA-B and ORF beta C1 in satellite DNA beta which  are predicted to function as silencing suppressors. In the present study suppressor function of ORF beta C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl Multan betasatellite CLCuMB-[IN:Sri:02] and Luffa leaf distortion betasatellite LuLDB-[IN:Lu:04] were examined. Agroinfiltration of GFP-silenced Nicotiana tabaccum cv. Xanthi with the cells expressing betaC1 protein resulted in reversal of silenced GFP expression. GFP-siRNA level was more than 50-fold lower compared to silenced plants in plants infiltrated with betaC1 gene from ToLCBB. However, in the case of 35S-beta C1 CLCuMB and 35S- beta C1 LuLDB construct, although GFP was expressed, siRNA level was not reduced, indicating that the step at which beta C1 interfere in RNA-silencing pathway is different.
authors: Advanced Centre for Plant Virology, Div. of Plant Pathology, Indian Agricultural Research Institute, New Delhi 110 012.
authors: Richa
authors: R
authors: Shukla
authors: Sunita
authors: S
authors: Dalal
authors: V G
authors: VG
authors: Malathi
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics; D000818:Animals; D053839:Begomovirus / Q000235:genetics*; D004276:DNA, Satellite; D004279:DNA, Viral; D017930:Genes, Reporter; D016153:Genes, Suppressor; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D006430:Hemiptera / Q000821:virology; D018551:Solanum lycopersicum / Q000235:genetics* / Q000276:immunology / Q000821:virology; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000821:virology; D018515:Plant Leaves / Q000235:genetics* / Q000276:immunology / Q000821:virology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D014026:Nicotiana / Q000235:genetics / Q000382:microbiology
chemical_list: D004276:DNA, Satellite; D004279:DNA, Viral; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins
references: Virology. 2007 Feb 5;358(1):159-65
references: 16979684
references: Nature. 2000 Mar 16;404(6775):293-6
references: 10749213
references: J Virol. 2004 Dec;78(24):13966-74
references: 15564504
references: Virus Res. 2010 Apr;149(1):19-27
references: 20079777
references: J Virol. 2005 Feb;79(4):2517-27
references: 15681452
references: Arch Virol. 2010 Aug;155(8):1343-7
references: 20526636
references: J Virol. 2005 Aug;79(16):10764-75
references: 16051868
references: Virology. 2006 Jan 5;344(1):158-68
references: 16364747
references: Trends Plant Sci. 2011 May;16(5):265-72
references: 21439890
references: Annu Rev Phytopathol. 2005;43:191-204
references: 16078882
references: Arch Virol. 2007;152(7):1273-82
references: 17385070
references: Anal Biochem. 1983 Jul 1;132(1):6-13
references: 6312838
references: Nature. 2004 Sep 16;431(7006):356-63
references: 15372043
references: Proc Natl Acad Sci U S A. 2000 Nov 21;97(24):13401-6
references: 11078509
references: Virus Res. 2007 Jan;123(1):9-18
references: 16949698
references: J Virol. 2004 Sep;78(17):9487-98
references: 15308741
references: Virology. 2006 Jan 5;344(1):198-210
references: 16364750
references: Mol Plant Pathol. 2004 Jan 1;5(1):71-82
references: 20565584
references: J Gen Virol. 2007 Oct;88(Pt 10):2881-2889
references: 17872543
references: Virology. 2003 Jul 20;312(1):106-21
references: 12890625
references: J Virol Methods. 2008 Jan;147(1):37-42
references: 17870189
references: Proc Natl Acad Sci U S A. 1999 Nov 23;96(24):14147-52
references: 10570213
references: Virology. 2003 Jan 20;305(2):310-7
references: 12573576
references: Virus Res. 2004 Jun 1;102(1):97-108
references: 15068885
references: Trends Genet. 2001 Aug;17(8):449-59
references: 11485817
references: Methods Mol Biol. 2008;442:187-203
references: 18369787