CP and infection: In contrast, attenuation of MLB2 virus with a small 5-nucleotide out-of-frame deletion resulted in modest differences in replicon activity (Fig 5E), varying RNA levels depending on infection stage in Huh7.5.1 cells (Fig 5G), and 10-fold decreased RNA levels in neuronal infection (Fig 6G), suggesting that differences in cleaved C-terminal part of CP (Fig 1D) could play a major role in attenuation of MLB2.