3JCR: 3d Structure Determination Of The Human*u4/u6.u5* Tri-snrnp Complex

Citation:
Abstract
The U4/U6.U5 triple small nuclear ribonucleoprotein (tri-snRNP) is a major spliceosome building block. We obtained a three-dimensional structure of the 1.8-megadalton human tri-snRNP at a resolution of 7 angstroms using single-particle cryo-electron microscopy (cryo-EM). We fit all known high-resolution structures of tri-snRNP components into the EM density map and validated them by protein cross-linking. Our model reveals how the spatial organization of Brr2 RNA helicase prevents premature U4/U6 RNA unwinding in isolated human tri-snRNPs and how the ubiquitin C-terminal hydrolase-like protein Sad1 likely tethers the helicase Brr2 to its preactivation position. Comparison of our model with cryo-EM three-dimensional structures of the Saccharomyces cerevisiae tri-snRNP and Schizosaccharomyces pombe spliceosome indicates that Brr2 undergoes a marked conformational change during spliceosome activation, and that the scaffolding protein Prp8 is also rearranged to accommodate the spliceosome's catalytic RNA network.
PDB ID: 3JCRDownload
MMDB ID: 137117
PDB Deposition Date: 2016/1/21
Updated in MMDB: 2016/04
Experimental Method:
electron microscopy
Resolution: 7  Å
Source Organism:
Similar Structures:
Biological Unit for 3JCR: 36-meric; determined by author
Molecular Components in 3JCR
Label Count Molecule
Proteins (33 molecules)
1
Hprp6(Gene symbol: PRPF6)
Molecule annotation
1
U5-40k(Gene symbol: SNRNP40)
Molecule annotation
1
Hbrr2(Gene symbol: SNRNP200)
Molecule annotation
1
Hdim1(Gene symbol: TXNL4A)
Molecule annotation
1
Hprp8(Gene symbol: PRPF8)
Molecule annotation
1
Hprp28(Gene symbol: DDX23)
Molecule annotation
1
Hsnu114(Gene symbol: EFTUD2)
Molecule annotation
2
SMB(Gene symbol: SNRPB)
Molecule annotation
2
Smd1(Gene symbol: SNRPD1)
Molecule annotation
2
Smd2(Gene symbol: SNRPD2)
Molecule annotation
2
Smd3(Gene symbol: SNRPD3)
Molecule annotation
2
SME(Gene symbol: SNRPE)
Molecule annotation
2
SMF(Gene symbol: SNRPF)
Molecule annotation
2
SMG(Gene symbol: SNRPG)
Molecule annotation
1
Lsm8(Gene symbol: LSM8)
Molecule annotation
1
Lsm6(Gene symbol: LSM6)
Molecule annotation
1
Lsm5(Gene symbol: LSM5)
Molecule annotation
1
Lsm4(Gene symbol: LSM4)
Molecule annotation
1
Lsm3(Gene symbol: LSM3)
Molecule annotation
1
Lsm2(Gene symbol: LSM2)
Molecule annotation
1
Lsm7(Gene symbol: LSM7)
Molecule annotation
1
Hprp3(Gene symbol: PRPF3)
Molecule annotation
1
Hprp4
Molecule annotation
1
Hprp31(Gene symbol: PRPF31)
Molecule annotation
1
Hsnu13(Gene symbol: SNU13)
Molecule annotation
1
Hsad1(Gene symbol: USP39)
Molecule annotation
Nucleotides(3 molecules)
1
U4 Snrna
Molecule annotation
1
U6 Snrna
Molecule annotation
1
U5 Snrna
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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