Biomaterial Database

The U1 small nuclear ribonucleoprotein/5' splice site interaction affects U2AF65 binding to the downstream 3' splice site. 1995

J Côté, and J Beaudoin, and R Tacke, and B Chabot

Département de Microbiologie, Faculté de Médecine, Université de Sherbrooke, Québec, Canada.

In the gene of the neural cell adhesion molecule, the 5' splice site of the alternate exon 18 plays an important role in establishing regulated splicing profiles. To understand how the 5' splice site of exon 18 contributes to splicing regulation, we have investigated the interaction of the U2AF65 splicing factor to pre-mRNAs that contained portions of the constitutive exon 17 or the alternate exon 18 fused to exon 19 and separated by a shortened intron. Despite sharing an identical 3' splice site, only the pre-mRNA that contained a portion of exon 17 and its associated 5' splice site displayed efficient U2AF65 cross-linking. Strikingly, a G-->U mutation at position +6 of the intron, converting the 5' splice site of exon 18 into that of exon 17, stimulated U2AF65 crosslinking. The improved cross-linking efficiency of U2AF65 to a pre-mRNA carrying the 5' splice site of exon 17 required the integrity of the 5' end of U1 but not of U2 small nuclear RNA. Our results indicate that neural cell adhesion molecule 5' splice site sequences influence U2AF65 binding through a U1 small nuclear ribonucleoprotein/U2AF interaction that occurs at the commitment stage of spliceosome assembly, before stable binding of the U2 small nuclear ribonucleoprotein. Thus, the 5' splice sites of exons 17 and 18 differentially affect U2AF65 binding to the 3' splice site of exon 19. Factors that modulate U1 small nuclear ribonucleoprotein binding to these 5' splice sites may play a critical role in regulating exon 18 skipping.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009687	Nuclear Proteins	Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.	Nucleolar Protein,Nucleolar Proteins,Nuclear Protein,Protein, Nuclear,Protein, Nucleolar,Proteins, Nuclear,Proteins, Nucleolar
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D005091	Exons	The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.	Mini-Exon,Exon,Mini Exon,Mini-Exons
D000072668	Splicing Factor U2AF	An RNA splicing factor that performs a critical function in both constitutive and enhancer-dependent RNA SPLICING. It recruits RIBONUCLEOPROTEIN, U2 SMALL NUCLEAR to the splice site and mediates interactions between it, the RNA molecule, and other splicing factors for accurate 3'-splice site selection.	U2AF 65,U2AF Splicing Factor,U2AF(65),Factor U2AF, Splicing,Factor, U2AF Splicing,Splicing Factor, U2AF,U2AF, Splicing Factor
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D012261	Ribonucleoproteins	Complexes of RNA-binding proteins with ribonucleic acids (RNA).	Ribonucleoprotein
D012326	RNA Splicing	The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.	RNA, Messenger, Splicing,Splicing, RNA,RNA Splicings,Splicings, RNA
D017412	Ribonucleoprotein, U1 Small Nuclear	A nuclear RNA-protein complex that plays a role in RNA processing. In the nucleoplasm, the U1 snRNP along with other small nuclear ribonucleoproteins (U2, U4-U6, and U5) assemble into SPLICEOSOMES that remove introns from pre-mRNA by splicing. The U1 snRNA forms base pairs with conserved sequence motifs at the 5'-splice site and recognizes both the 5'- and 3'-splice sites and may have a fundamental role in aligning the two sites for the splicing reaction.	Small Nuclear Ribonucleoproteins, U1,U1 Small Nuclear Ribonucleoproteins,U1 snRNP,Ribonucleoproteins, Small, U1
D017931	DNA Primers	Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.	DNA Primer,Oligodeoxyribonucleotide Primer,Oligodeoxyribonucleotide Primers,Oligonucleotide Primer,Oligonucleotide Primers,Primer, DNA,Primer, Oligodeoxyribonucleotide,Primer, Oligonucleotide,Primers, DNA,Primers, Oligodeoxyribonucleotide,Primers, Oligonucleotide