8Y7E

Cryo-EM Structure of the human minor pre-B complex (pre-precatalytic spliceosome) U12 snRNP part

Summary for 8Y7E

• Entry DOI: 10.2210/pdb8y7e/pdb
• EMDB information: 39013
• Descriptor: pre-mRNA, Small nuclear ribonucleoprotein Sm D3, Small nuclear ribonucleoprotein-associated proteins B and B', ... (18 entities in total)
• Functional Keywords: spliceosome, minor spliceosome, u11 snrnp, u12 snrnp, u4atac, u6atac, cenatac, txnl4b, u11 snrna, minor tri-snrnp, u12-type intron, splicing/rna, splicing-rna complex
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 17
• Total formula weight: 722538.24

Authors

Bai, R.,Yuan, M.,Zhang, P.,Luo, T.,Shi, Y.,Wan, R. (deposition date: 2024-02-04, release date: 2024-03-13, Last modification date: 2024-10-23)

Primary citation

Bai, R.,Yuan, M.,Zhang, P.,Luo, T.,Shi, Y.,Wan, R.
Structural basis of U12-type intron engagement by the fully assembled human minor spliceosome.
Science, 383:1245-1252, 2024

PubMed Abstract: The minor spliceosome, which is responsible for the splicing of U12-type introns, comprises five small nuclear RNAs (snRNAs), of which only one is shared with the major spliceosome. In this work, we report the 3.3-angstrom cryo-electron microscopy structure of the fully assembled human minor spliceosome pre-B complex. The atomic model includes U11 small nuclear ribonucleoprotein (snRNP), U12 snRNP, and U4atac/U6atac.U5 tri-snRNP. U11 snRNA is recognized by five U11-specific proteins (20K, 25K, 35K, 48K, and 59K) and the heptameric Sm ring. The 3' half of the 5'-splice site forms a duplex with U11 snRNA; the 5' half is recognized by U11-35K, U11-48K, and U11 snRNA. Two proteins, CENATAC and DIM2/TXNL4B, specifically associate with the minor tri-snRNP. A structural analysis uncovered how two conformationally similar tri-snRNPs are differentiated by the minor and major prespliceosomes for assembly.

PubMed: 38484052
DOI: 10.1126/science.adn7272

Experimental method

ELECTRON MICROSCOPY (4.66 Å)