, Volume 30, Issue 1, pp 101–105 | Cite as

The Rep proteins encoded by alphasatellites restore expression of a transcriptionally silenced green fluorescent protein transgene in Nicotiana benthamiana

  • Qamar Abbas
  • Imran Amin
  • Shahid Mansoor
  • Muhammad Shafiq
  • Michael Wassenegger
  • Rob W. BriddonEmail author
Short Communication


Alphasatellites are non-essential satellite-like components associated with geminiviruses. The precise selective advantage to a geminivirus infection of an alphasatellite remains unclear. The ability of the cotton leaf curl Multan alphasatellite (CLCuMuA)-encoded replication-associated protein (Rep) to suppress TGS was investigated by using Nicotiana benthamiana line 16-TGS (16-TGS) harbouring a transcriptionally silenced green fluorescent protein (GFP) transgene. Inoculation of 16-TGS plants with a recombinant Potato virus X (PVX) vector carrying CLCuMuA Rep resulted in restoration of GFP expression. Northern blot analysis confirmed that the observed GFP fluorescence was associated with GFP mRNA accumulation. Inoculation with PVX vectors harbouring a further six Rep proteins, encoded by genetically distinct alphasatellites, were similarly shown to result in 16-TGS plants with restored GFP expression. These results indicate that the alphasatellite-encoded Rep can restore the expression of a transcriptionally silenced GFP transgene in N. benthamiana, indicating that alphasatellites are involved in overcoming host defence.


Alphasatellite Geminivirus RNA interference Transcriptional gene silencing 



The authors are grateful to Arvind Varsani for providing the CLCuGeA and DfasA clones. QA and MS were supported by indigenous Ph.D. scholarships from the Higher Education Commission (HEC), Government of Pakistan. RWB was supported by the HEC under the “Foreign Faculty Hiring Program”.


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Copyright information

© Indian Virological Society 2017

Authors and Affiliations

  1. 1.National Institute for Biotechnology and Genetic EngineeringFaisalabadPakistan
  2. 2.RLP-AgroscienceAlPlanta - Institute for Plant ResearchNeustadtGermany
  3. 3.Department of Crop Sciences, College of Agricultural and Marine SciencesSultan Qaboos UniversityMuscatOman

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