FIG. 1.

Identification of PCIF1 in a yeast two-hybrid screen using the C terminus of PDX-1 as bait. (A) Diagram depicting the structure of PDX-1 and the region encoded in the bait vector. DBD, DNA binding domain. HD, homeodomain. (B) Diagram depicting the structure of PCIF1 and the portion encoded by the interacting clone. (C) GST pull-down assay demonstrating a specific interaction between the C terminus of PDX-1 and PCIF1. GST fusion proteins were incubated with in vitro-transcribed and -translated ³⁵S-labeled PCIF1. After washing, proteins bound to glutathione beads were analyzed by gel electrophoresis, dried, and exposed to film. Lanes: 1, 10% of the in vitro-transcribed and -translated product used in the assay; 2, GST; 3, GST-PDX-1(206-283); 4, GST-PDX-1(144-283). The position of ³⁵S-labeled PCIF1 is indicated by an arrow. IVTT, in vitro-transcribed and -translated product; MW, molecular weight (in thousands).