Fig. 3.

Electrophoretic mobility shift assay to investigate binding of the Leishmania PABPs to an A-rich RNA probe. The assay was performed by incubating the ³²P-labeled A-rich probe described in the text with a fixed amount (100 ng) of the three recombinant GST fusions and analysis on a 5% nondenaturing polyacrylamide gel. Shifts obtained in the presence of the proteins were compared with the probe on its own. Where stated, the binding reactions were supplemented with 1 or 10 μg/ml of the polynucleotide poly(A), poly(C), or poly(U).