FIG. 8.

TbMT417 and TbMT511 bind the mRNA m⁷G cap. A. Purified TbMT417 protein was incubated with ³²P-labeled, uncapped RNA probe alone (lane 2) and in the presence of a fivefold molar excess of unlabeled uncapped RNA transcript (lane 3) as a competitor. Similarly, radiolabeled RNA with m⁷G cap at the 5′ end (lane 4) was used as substrate for binding to TbMT417 alone (lane 5) or in the presence of a fivefold molar excess of cold uncapped competitor RNA (lane 6). B. Binding experiments were performed with m⁷G-capped RNA as substrate (lane 1), using 50 ng of purified wild-type (WT) TbMT417 (lane 2) or 50 ng (lane 3) or 250 ng (lane 4) of a mutated form (Y18A) of TbMT417. C. Same as B, but purified wild-type (lane 2) or mutated Y49A forms (lanes 3 and 4) of recombinant TbMT511 were used in the binding experiments.