Document Detail


Functional spliceosomal A complexes can be assembled in vitro in the absence of a penta-snRNP.
MedLine Citation:
PMID:  16880538     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Two different models currently exist for the assembly pathway of the spliceosome, namely, the traditional model, in which spliceosomal snRNPs associate in a stepwise, ordered manner with the pre-mRNA, and the holospliceosome model, in which all spliceosomal snRNPs preassemble into a penta-snRNP complex. Here we have tested whether the spliceosomal A complex, which contains solely U1 and U2 snRNPs bound to pre-mRNA, is a functional, bona fide assembly intermediate. Significantly, A complexes affinity-purified from nuclear extract depleted of U4/U6 snRNPs (and thus unable to form a penta-snRNP) supported pre-mRNA splicing in nuclear extract depleted of U2 snRNPs, whereas naked pre-mRNA did not. Mixing experiments with purified A complexes and naked pre-mRNA additionally confirmed that under these conditions, A complexes do not form de novo. Thus, our studies demonstrate that holospliceosome formation is not a prerequisite for generating catalytically active spliceosomes and that, at least in vitro, the U1 and U2 snRNPs can functionally associate with the pre-mRNA, prior to and independent of the tri-snRNP. The ability to isolate functional spliceosomal A complexes paves the way to study in detail subsequent spliceosome assembly steps using purified components.
Authors:
Nastaran Behzadnia; Klaus Hartmuth; Cindy L Will; Reinhard Lührmann
Related Documents :
10489348 - Novel, nonconsensus cellular splicing regulates expression of a gene encoding a chemoki...
14756308 - Post-transcriptional regulation of expression of the bronze2 gene of zea mays l.
9813338 - A sequence-specific splicing activator, tra2beta, is up-regulated in response to nerve ...
14612138 - Norepinephrine transporter splice variants and their interaction with substrates and bl...
9453398 - Compartmental localization of complement component transcripts in the normal human kidney.
1576018 - Modulation of thrombospondin gene expression during osteoblast differentiation in mc3t3...
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't     Date:  2006-07-31
Journal Detail:
Title:  RNA (New York, N.Y.)     Volume:  12     ISSN:  1355-8382     ISO Abbreviation:  RNA     Publication Date:  2006 Sep 
Date Detail:
Created Date:  2006-08-31     Completed Date:  2006-09-25     Revised Date:  2013-06-07    
Medline Journal Info:
Nlm Unique ID:  9509184     Medline TA:  RNA     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1738-46     Citation Subset:  IM    
Affiliation:
Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, D-37077 Göttingen, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
HeLa Cells
Humans
RNA Precursors / genetics,  metabolism*
RNA Splicing*
Ribonucleoproteins, Small Nuclear / genetics,  isolation & purification,  metabolism*
Spliceosomes / genetics,  metabolism*
Chemical
Reg. No./Substance:
0/RNA Precursors; 0/Ribonucleoproteins, Small Nuclear
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Bloom helicase and DNA topoisomerase IIIalpha are involved in the dissolution of sister chromatids.
Next Document:  Structure of Staphylococcus aureus cytidine monophosphate kinase in complex with cytidine 5'-monopho...