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-Structure paper
Title | Structure of a yeast activated spliceosome at 3.5 Å resolution. |
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Journal, issue, pages | Science, Vol. 353, Issue 6302, Page 904-911, Year 2016 |
Publish date | Aug 26, 2016 |
Authors | Chuangye Yan / Ruixue Wan / Rui Bai / Gaoxingyu Huang / Yigong Shi / |
PubMed Abstract | Pre-messenger RNA (pre-mRNA) splicing is carried out by the spliceosome, which undergoes an intricate assembly and activation process. Here, we report an atomic structure of an activated spliceosome ...Pre-messenger RNA (pre-mRNA) splicing is carried out by the spliceosome, which undergoes an intricate assembly and activation process. Here, we report an atomic structure of an activated spliceosome (known as the B(act) complex) from Saccharomyces cerevisiae, determined by cryo-electron microscopy at an average resolution of 3.52 angstroms. The final refined model contains U2 and U5 small nuclear ribonucleoprotein particles (snRNPs), U6 small nuclear RNA (snRNA), nineteen complex (NTC), NTC-related (NTR) protein, and a 71-nucleotide pre-mRNA molecule, which amount to 13,505 amino acids from 38 proteins and a combined molecular mass of about 1.6 megadaltons. The 5' exon is anchored by loop I of U5 snRNA, whereas the 5' splice site (5'SS) and the branch-point sequence (BPS) of the intron are specifically recognized by U6 and U2 snRNA, respectively. Except for coordination of the catalytic metal ions, the RNA elements at the catalytic cavity of Prp8 are mostly primed for catalysis. The catalytic latency is maintained by the SF3b complex, which encircles the BPS, and the splicing factors Cwc24 and Prp11, which shield the 5' exon-5'SS junction. This structure, together with those determined earlier, outlines a molecular framework for the pre-mRNA splicing reaction. |
External links | Science / PubMed:27445306 |
Methods | EM (single particle) |
Resolution | 3.5 Å |
Structure data | |
Chemicals | ChemComp-GTP: ChemComp-MG: ChemComp-ZN: ChemComp-ADP: |
Source |
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Keywords | RNA BINDING PROTEIN/RNA / spliceosome / RNA splicing / Bact / Catalytically activated / RNA BINDING PROTEIN-RNA complex |