Figure 1.

Prp24 binds U6 RNA with high affinity and specificity. (A) Top: primary structure of Prp24. White regions are disordered and were deleted from the crystallization construct as previously described (24). RRM4 is an occluded RRM (oRRM), with terminal α-helices masking its β-sheet face (22,24). Unless indicated otherwise, all assays herein used full-length protein and RNA. Bottom: molecular architecture of the U6 snRNP core. Regions of U6 RNA (black) that form U4/U6 Stem I and Stem II are highlighted in green and purple, respectively. (B) Schematic of U6 RNA annealing to U4 RNA to form U4/U6. (C) Native gel analysis of full-length Prp24 binding to U6 (top) and U4 (bottom) RNAs.