Detection of HBoV1 NS1, NS2, NS3, and NS4 proteins in HEK293 cells transfected with pHBoV1NSCap-based plasmids. (A and B) Expression of HBoV1 NS2 protein. (A) Expected HA-tagged NS proteins expressed from pHBoV1NS1HA303*Cap. The NS-encoding viral mRNAs, which have the potential to produce HA-tagged NS proteins and C terminus-containing NS proteins, are diagramed. The expected NS proteins and their predicted and detected sizes are shown at the right. (B) HEK293 cells were transfected with pHBoV1NS1HACap or pHBoV1NS1HA303*Cap as indicated. At 2 days posttransfection, cells were lysed for Western blotting using an anti-HA antibody. (C and D) Expression of HBoV1 NS3 and NS4 proteins. (C) Expected NS1 C terminus (NS1C)-containing NS proteins expressed from pHBoV1NS1HA65*Cap and pHBoV1NS1HA65*303*Cap. The NS-encoding viral mRNAs, which have the potential to produce NS1C-containing NS proteins, are diagramed. The expected NS proteins and their predicted and detected sizes are shown at the right. (D) HEK293 cells were transfected with pHBoV1NSCap-based plasmids as indicated. At 2 days posttransfection, cells were lysed for Western blotting using the anti-NS1C antibody.