Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Home
Search
Quick Search
Advanced
Fulltext
Browse
Collections
Persons
My eDoc
Session History
Login
Name:
Password:
Documentation
Help
Support Wiki
Direct access to
document ID:


          Institute: MPI für molekulare Zellbiologie und Genetik     Collection: MPI-CBG Publications 2013 (arch)     Display Documents



ID: 688544.0, MPI für molekulare Zellbiologie und Genetik / MPI-CBG Publications 2013 (arch)
The nuclear cap-binding complex interacts with the U4/U6·U5 tri-snRNP and promotes spliceosome assembly in mammalian cells
Authors:Pabis, Marta; Neufeld, Noa; Steiner, Michaela; Bojic, Teodora; Shav-Tal, Yaron; Neugebauer, Karla M.
Date of Publication (YYYY-MM-DD):2013
Title of Journal:RNA (New York, N.Y.)
Volume:19
Issue / Number:8
Start Page:1054
End Page:1063
Copyright:not available
Audience:Experts Only
Intended Educational Use:No
Abstract / Description:The nuclear cap-binding complex (CBC) binds to the 7-methyl guanosine cap present on every RNA polymerase II transcript. CBC has been implicated in many aspects of RNA biogenesis; in addition to roles in miRNA biogenesis, nonsense-mediated decay, 3'-end formation, and snRNA export from the nucleus, CBC promotes pre-mRNA splicing. An unresolved question is how CBC participates in splicing. To investigate CBC's role in splicing, we used mass spectrometry to identify proteins that copurify with mammalian CBC. Numerous components of spliceosomal snRNPs were specifically detected. Among these, three U4/U6·U5 snRNP proteins (hBrr2, hPrp4, and hPrp31) copurified with CBC in an RNA-independent fashion, suggesting that a significant fraction of CBC forms a complex with the U4/U6·U5 snRNP and that the activity of CBC might be associated with snRNP recruitment to pre-mRNA. To test this possibility, CBC was depleted from HeLa cells by RNAi. Chromatin immunoprecipitation and live-cell imaging assays revealed decreased cotranscriptional accumulation of U4/U6·U5 snRNPs on active transcription units, consistent with a requirement for CBC in cotranscriptional spliceosome assembly. Surprisingly, recruitment of U1 and U2 snRNPs was also affected, indicating that RNA-mediated interactions between CBC and snRNPs contribute to splicing. On the other hand, CBC depletion did not impair snRNP biogenesis, ruling out the possibility that decreased snRNP recruitment was due to changes in nuclear snRNP concentration. Taken together, the data support a model whereby CBC promotes pre-mRNA splicing through a network of interactions with and among spliceosomal snRNPs during cotranscriptional spliceosome assembly.
External Publication Status:published
Document Type:Article
Communicated by:Lib
Affiliations:MPI für molekulare Zellbiologie und Genetik
Identifiers:LOCALID:5500
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.