FIGURE 5.

Cap binding of hDcp2 is RNA dependent. (A) hDcp2 can be UV cross-linked to cap-labeled RNA. An autoradiograph of an SDS-PAGE showing 10 pmole of the indicated protein cross-linked to ³²P-cap-labeled pcP-G₁₆ RNA. Cross-linking of the eIF4E cap-binding protein (GST–eIF4E, 50 kD; lanes 1,4) was used as a positive control. An unrelated GST–mDAZL RNA-binding protein (68 kD; lane 3), or purification of a His-tag empty vector (lane 9) are shown as negative controls. The sizes of the hDcp2 proteins and truncations are as described in the legend to Figure 4 ▶. The capped RNA substrate is shown at bottom, where the line represents the RNA and the star denotes the labeled phosphate.