In plants, eukaryotic translation elongation factor 1B (eEF1B) is composed of three subunits, eEF1Bα, eEF1Bβ and eEF1B γ. Two subunits are nucleotide exchange subunits (eEF1Bα and eEF1Bβ) and one is a structural protein (eEF1Bγ). In the previous study, eEF1B was identified as a common host factor for several RNA viruses. To test which subunit of eEF1B is essential for Potato virus X (PVX) replication, the virus-induced gene silencing (VIGS) for eEF1Bα, β or γ was performed in Nicotiana benthamiana and green fluorescent protein (GFP)-tagged PVX was inoculated. PVX-GFP accumulation was decreased when eEF1Bβ or γ subunit was silenced, whereas eEF1Bα had no effect on PVX-GFP accumulation in inoculated leaves. Targeting induced local lesions in genome (TILLING) was performed using a Capsicum annuum EMS population to test whether mutations in eEF1Bβ subunit affect virus infection in pepper. We obtained 81 eEF1Bβ mutant lines consisted of 16,759 individuals. These mutant lines are being tested to validate the function of eEF1B β in PVX replication.