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PubMed · 8514198

Alternative 3' splice-site selection using HeLa cell nuclear extracts prepared with high-ionic buffers.

K Zerivitz·J P Kreivi·G Akusjärvi
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Abstract

To investigate the role of cellular trans-acting factors in alternative 3' splice-site selection, a series of HeLa cell nuclear extracts were generated with salt washes ranging from 0.4 to 0.8 M salt. These extracts were tested with human beta-globin pre-mRNAs containing tandem 5' or 3' splice-site duplications as the substrates. High-salt (0.6 M and higher)-based buffers generated nuclear extracts that differentially processed pre-mRNAs containing competing 3' splice sites. High-salt extracts increased the usage of the distal 3' splice site, whereas no shift in 5' splice-site usage could be detected. Western analysis suggested that this shift in alternative 3' splice-site selection was not due to changes in the U2 snRNP auxiliary factor or polypyrimidine tract-binding protein levels.

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Alternative SplicingBlotting, WesternElectrophoresis, Polyacrylamide GelGlobinsHeLa CellsHumansNuclear ProteinsPolypyrimidine Tract-Binding ProteinRNA PrecursorsRNA, MessengerRNA, Small NuclearRNA-Binding ProteinsRibonucleoproteinsSplicing Factor U2AFTranscriptional ActivationJournal ArticleResearch Support, Non-U.S. Gov't

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K Zerivitz, J P Kreivi, G Akusjärvi. 1993-06-30. Alternative 3' splice-site selection using HeLa cell nuclear extracts prepared with high-ionic buffers.. https://doi.org/10.1016/0378-1119(93)90579-r

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