Extended Data Fig. 7: Release of mRNP and spliceosome proteins from the post-catalytic spliceosome unmasks binding sites for the disassembly factors.
From: Mechanism for the initiation of spliceosome disassembly
a. Overview cartoon, placing the depicted structures into context of the spliceosome disassembly pathway. b. Structural comparison of the structures of the P complex (Model of a Ce P complex based on the updated human P complex, this work), the intron lariat spliceosome immediately after mRNP release (modelled) and the ILS′ (Ce structure, this work). Proteins thar are exchanged in the transition are labelled. Numbers indicate regions for zoom ins in panels c-e. c. Overlay and close-up view of the P-complex structure with the ILS′ reveals a clash of TFIP11 with the EJC (EIF4A3 subunit) and with CWC22, NOSIP, and SRRM2 in the P complex. This clash would occur both in the ILS′ and ILS″. Clashing proteins are outlined in black. d. Overlay and close-up view of the P complex structure with the ILS′ reveals a clash between PPWD1 and PAXBP1 on BRR2. e. Overlay and close-up view of the P complex structure with the ILS″ reveals a clash between C19L2 and the path of the ligated exons in the P-complex.
