Fig. 6

Restriction of KoRV replication by human and mouse APOBEC3s. 293T cells were cotransfected with pKoRV522 or pKoRV gg- along with plasmids expressing hA3G or mA3∆E5. The amount of CA released from the transfected 293T cells was measured by western blots. DERSE cells were infected with the resulting viruses with the similar inputs (measured by KoRV CA) and cell lysates of the infected DERSE cells were subjected to western blots with anti-KoRV CA (Additional file 1: Fig. S3). Relative infectivities of the different KoRV samples were assessed by quantifying the Gag signals by densitometry. The results were normalized for the amounts of the viruses used for infection. All values are shown relative to the infectivity of WT KoRV or KoRVgg- in the absence of any APOBEC3s. The experiments were repeated at least 3 times and the error bars indicate standard deviation (a, b). a The relative infectivity of KoRVgg- to KoRV522 is shown, where the infectivity of KoRV522 was set as 1. b The effects of co-transfecting different APOBEC3 expression plasmids on the infectivities of WT (pKoRV522) or KoRVgg- virus is shown. The APOBEC3 plasmids were co-transfected into the 293T cells at a 1:1 ratio with the KoRV expression plasmids. Relative viral infectivity to the control virus (without APOBECs) is shown. The experiments in (a) and (b) were repeated at least three times and the standard deviations are shown. The effects of co-transfecting different amounts of hA3G (c) or mA3∆E5 (d) with pKoRV522 in the 293T cells on the relative viral infectivity of WT KoRV in DERSE cells is shown. In d, it was not possible to obtain enough virus from the co-transfections at a 1:3 ratio for mA3∆E5 for the infectivity assay due to the inhibitory effect of this plasmid on KoRV expression (ND).