FIGURE 6.

Medulloblastoma-associated variants inactivate DDX3. A, motifs Ia and VI of human DEAD-box proteins with residues altered in the medulloblastoma indicated. B, RNA duplex unwinding conducted with DDX3 132–607 and recurrent medulloblastoma variants indicated. Error bars indicate standard error of the fit parameter. C, yeast with mutations at DED1 Arg-235 to alanine or lysine are tolerated, whereas R235Y, R492A, and R492H were nonviable (not shown). DED1 Arg-235 and Arg-492 correspond to DDX3 Arg-276 and Arg-534, respectively.