Formation of the Spliceosomal Pre-B complex

Stable Identifier
R-HSA-9770132
Type
Reaction [uncertain]
Species
Homo sapiens
Compartment
nucleoplasm
ReviewStatus
5/5
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Formation of the Spliceosomal Pre-B complex
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The U4/U6.U5 tri-snRNP complex loosely binds the Spliceosomal A complex to form the Spliceosomal Pre-B complex (Boesler et al. 2016). The U4/U6.U5 tri-snRNP comprises the U4 snRNA base-paired with the U6 snRNA within U4/U6 di-snRNP, the U5 snRNP and tri-snRNP specific factors. The 3' end of the U2 snRNA is bound to the branch point sequence which leaves the 5' end of the U2 snRNA free to base-pair with the 3' end of the U6 from the tri-snRNP (Hausner et al. 1990, Boesler et al. 2016). In addition, the SF3A1 component of the U2 snRNP binds the U4/U6 region of tri-snRNP (Charenton et al. 2019). U1 snRNP, bound to the 5’splice site transiently interacts with tri-snRNP proximal to the DDX23 helicase and U6 and U5 acceptor sequences. The PRPF4B kinase involved B complex formation via phosphorylation of tri-snRNP components, is loosely bound to the pre-B complex. The components of the Spliceosomal Pre-B complex have been ascertained using proteomic and structural methods (Boesler et al. 2016, Zhan et al. 2018, Charenton et al. 2019)..
Literature References
PubMed ID Title Journal Year
23222130 Aly and THO are required for assembly of the human TREX complex and association of TREX components with the spliced mRNA

Chang, X, Shi, M, Wu, G, Chi, B, Wang, L, Tan, M, Wang, Q, Cheng, H

Nucleic Acids Res. 2013
30975767 Mechanism of 5' splice site transfer for human spliceosome activation

Charenton, C, Wilkinson, ME, Nagai, K

Science 2019
30315277 Structures of the human pre-catalytic spliceosome and its precursor spliceosome

Shi, Y, Yan, C, Zhang, X, Lei, J, Zhan, X

Cell Res 2018
30765414 Structural Insights into Nuclear pre-mRNA Splicing in Higher Eukaryotes

Will, CL, Lührmann, R, Stark, H, Kastner, B

Cold Spring Harb Perspect Biol 2019
26385511 Stable tri-snRNP integration is accompanied by a major structural rearrangement of the spliceosome that is dependent on Prp8 interaction with the 5' splice site

Will, CL, Lührmann, R, Rigo, N, Agafonov, DE, Urlaub, H, Boesler, C, Kastner, B

RNA 2015
2176635 Evidence for base-pairing between mammalian U2 and U6 small nuclear ribonucleoprotein particles

Giglio, LM, Hausner, TP, Weiner, AM

Genes Dev 1990
14625303 A simple whole cell lysate system for in vitro splicing reveals a stepwise assembly of the exon-exon junction complex

Kataoka, N, Dreyfuss, G

J Biol Chem 2004
33243851 Mechanism of protein-guided folding of the active site U2/U6 RNA during spliceosome activation

Bertram, K, Will, CL, Lührmann, R, Leelaram, MN, Dybkov, O, Agafonov, DE, Stark, H, Urlaub, H, Townsend, C, Kastner, B

Science 2020
27377154 A spliceosome intermediate with loosely associated tri-snRNP accumulates in the absence of Prp28 ATPase activity

Tauchert, MJ, Will, CL, Rigo, N, Anokhina, MM, Agafonov, DE, Luhrmann, R, Urlaub, H, Boesler, C, Ficner, R, Kastner, B

Nat Commun 2016
Participants
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Output
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as an event of
Authored
May, B  (2022-03-22)
Reviewed
Charenton, C  (2022-10-20)
Created
May, B  (2022-03-24)
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