Figure 8: HNF4 interacts with DDX3 through one of its SHP-interacting domains.

(a) Schematic representation of the GST fusion proteins containing N-terminal, middle and C-terminal regions of HNF4. The binding results of the GST pull down analysis shown in Fig. 6b are summarized. (b) Mapping the interaction domains of DDX3 and SHP with HNF4. The GST and GST-HNF4 truncated derivatives prebound with glutathione Sepharose beads were incubated with whole cell lysates (500 μg) from HuH7 cells expressing HA-DDX3 and HA-SHP, respectively. After extensive wash, the bound proteins were resolved by SDS-PAGE and analyzed by Western blot with anti-HA antibody. Lane 5, input: total cell lysate (20 μg) of HuH7 cells expressing HA-tagged DDX3 or HA-tagged SHP. Lane 6, total cell lysate (20 μg) of HuH7 cells. Coomassie brilliant blue staining of the GST-HNF4 truncated derivatives is shown in the lower panel.