Structural basis of U12-type intron engagement by the fully assembled human minor spliceosome.
Science
; 383(6688): 1245-1252, 2024 Mar 15.
Article
em En
| MEDLINE
| ID: mdl-38484052
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.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Íntrons
/
RNA Nuclear Pequeno
/
Spliceossomos
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article