Inera, Laboratoire de virologie et de biotechnologies végétales, Station de Kamboinsé, 01 BP 476 Ouagadougou 01, Burkina Faso, UMR UP-IRD-CNRS 5096, Centre IRD, 911, avenue Agropolis BP 64501, 34394 Montpellier Cedex 5, France, Université de Ouagadougou, CRSBAN, UFR SVT, 03 BP 7021 Ouagadougou 03, Burkina Faso
RNA silencing or Post-transcriptional gene silencing (PTGS) in plants is a fundamental defence mechanism against viruses, transgenes and transposons. Most viruses, if not all, are able to overcome RNA-silencing through the production of so-called “silencing suppressors” with counter-defence ability”. This strategy is well known for plant and animal viruses. Silencing suppressor proteins block the host RNA silencing by targeting different steps of the silencing pathway. In this review, we will focus on the major silencing suppressor proteins encoded by plant viruses and on the methods used to identify and characterize the molecular bases of silencing suppression.