Summary information and primary citation
- PDB-id
-
7aav;
DSSR-derived features in text and
JSON formats
- Class
- splicing
- Method
- cryo-EM (4.2 Å)
- Summary
- Human pre-bact-2 spliceosome core structure
- Reference
-
Townsend C, Leelaram MN, Agafonov DE, Dybkov O, Will CL,
Bertram K, Urlaub H, Kastner B, Stark H, Luhrmann R
(2020): "Mechanism
of protein-guided folding of the active site U2/U6 RNA
during spliceosome activation." Science,
370. doi: 10.1126/science.abc3753.
- Abstract
- Spliceosome activation involves extensive protein and
RNA rearrangements that lead to formation of a
catalytically active U2/U6 RNA structure. At present,
little is known about the assembly pathway of the latter
and the mechanism whereby proteins aid its proper folding.
Here, we report the cryo-electron microscopy structures of
two human, activated spliceosome precursors (that is,
pre-B<sub>act</sub> complexes) at core
resolutions of 3.9 and 4.2 angstroms. These structures
elucidate the order of the numerous protein exchanges that
occur during activation, the mutually exclusive
interactions that ensure the correct order of
ribonucleoprotein rearrangements needed to form the U2/U6
catalytic RNA, and the stepwise folding pathway of the
latter. Structural comparisons with mature
B<sub>act</sub> complexes reveal the molecular
mechanism whereby a conformational change in the scaffold
protein PRP8 facilitates final three-dimensional folding of
the U2/U6 catalytic RNA.
