Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
35
pubmed:dateCreated
1993-1-12
pubmed:abstractText
Previous studies of alternative splicing of the rat beta-tropomyosin gene have shown that nonmuscle cells contain factors that block the use of the skeletal muscle exon 7 (Guo, W., Mulligan, G. J., Wormsley, S., and Helfman, D. M. (1991) Genes & Dev. 5, 2095-2106). Using an RNA mobility-shift assay we have identified factors in HeLa cell nuclear extracts that specifically interact with sequences responsible for exon blockage. Here we present the purification to apparent homogeneity of a protein that exhibits these sequence specific RNA binding properties. This protein is identical to the polypyrimidine tract binding protein (PTB) which other studies have suggested is involved in the recognition and efficient use of 3'-splice sites. PTB binds to two distinct functional elements within intron 6 of the beta-tropomyosin pre-mRNA: 1) the polypyrimidine tract sequences required for the use of branch points associated with the splicing of exon 7, and 2) the intron regulatory element that is involved in the repression of exon 7. Our results demonstrate that the sequence requirements for PTB binding are different than previously reported and shows that PTB binding cannot be predicted solely on the basis of pyrimidine content. In addition, PTB fails to bind stably to sequences within intron 5 and intron 7 of beta-TM pre-mRNA, yet forms a stable complex with sequences in intron 6, which is not normally spliced in HeLa cells in vitro and in vivo. The nature of the interactions of PTB within this regulated intron reveals several new details about the binding specificity of PTB and suggests that PTB does not function exclusively in a positive manner in the recognition and use of 3'-splice sites.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
25480-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:1460042-Alternative Splicing, pubmed-meshheading:1460042-Animals, pubmed-meshheading:1460042-Base Sequence, pubmed-meshheading:1460042-Binding Sites, pubmed-meshheading:1460042-Cell Nucleus, pubmed-meshheading:1460042-Chromatography, Gel, pubmed-meshheading:1460042-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:1460042-Exons, pubmed-meshheading:1460042-Fibroblasts, pubmed-meshheading:1460042-Genes, pubmed-meshheading:1460042-HeLa Cells, pubmed-meshheading:1460042-Humans, pubmed-meshheading:1460042-Introns, pubmed-meshheading:1460042-Molecular Sequence Data, pubmed-meshheading:1460042-Molecular Weight, pubmed-meshheading:1460042-Muscle, Smooth, pubmed-meshheading:1460042-Muscles, pubmed-meshheading:1460042-Polypyrimidine Tract-Binding Protein, pubmed-meshheading:1460042-RNA Precursors, pubmed-meshheading:1460042-RNA-Binding Proteins, pubmed-meshheading:1460042-Rats, pubmed-meshheading:1460042-Transcription, Genetic, pubmed-meshheading:1460042-Tropomyosin
pubmed:year
1992
pubmed:articleTitle
Polypyrimidine tract binding protein interacts with sequences involved in alternative splicing of beta-tropomyosin pre-mRNA.
pubmed:affiliation
Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't