Identification and characterization of a novel bipartite nuclear localization signal in the hepatitis B virus polymerase

Figure 3 Binding of karyopherin-α2 to terminal protein depends on casein kinase II mediated phosphorylation. The interaction of soluble protein fraction of HuH-7 cells to immobilized terminal protein (TP) domain was investigated by western blotting of the sodium chloride eluted fractions 2-4. Karyopherin-α2 bound only to the casein kinase II (CKII) pre-treated TP column (upper panel). FP: Flow through of the CKII treated TP column; F: Flow trough of the untreated TP column.