Prp43 in the Spliceosome ILS Complex.
(A) Overall structure of the yeast ILS complex (PDB ID 5Y88). The light blue oval represents the likely location of the Ntr1 G-patch with insufficient density for modeling. (B) A zoomed in view of the Prp43-containing region of the ILS complex. Dotted lines indicate the distance from the U6 small nuclear RNA (snRNA) and the pre-mRNA to the Prp43 RNA-binding groove. (C) A model of how Prp43 translocation along the U6 snRNA could lead to spliceosome disassembly (adapted from [79]). Abbreviations: ILS, intron lariat spliceosome; NTC, NineTeen complex; NTR, NTC related.