Cellular and viral splicing factors can modify the splicing pattern of CFTR transcripts carrying splicing mutations

• Published in: Human molecular genetics Vol. 9; no. 12; pp. 1771 - 1778
• Main Authors: NISSIM-RAFINIA, M, CHIBA-FALEK, O, SHARON, G, BOSS, A, KEREM, B
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 22.07.2000; Oxford Publishing Limited (England)
• Subjects: 3T3 Cells; Adenovirus E4 Proteins - genetics; Adenovirus E4 Proteins - metabolism; Alternative Splicing; Animals; ASF/SF2 protein; Biological and medical sciences; COS Cells; Cystic Fibrosis - genetics; Cystic Fibrosis Transmembrane Conductance Regulator - genetics; E4-ORF3 protein; E4-ORF6 protein; Gastroenterology. Liver. Pancreas. Abdomen; Heterogeneous Nuclear Ribonucleoprotein A1; Heterogeneous-Nuclear Ribonucleoprotein Group A-B; Heterogeneous-Nuclear Ribonucleoproteins; hnRNP A1 protein; HT29 Cells; Humans; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Medical sciences; Mice; Mutation; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Other diseases. Semiology; Poly T; Ribonucleoproteins - genetics; Ribonucleoproteins - metabolism; RNA, Heterogeneous Nuclear; RNA, Messenger; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism; Serine-Arginine Splicing Factors; Tumor Cells, Cultured; Human; Adenoviridae; Respiratory disease; Cystic fibrosis; Gene expression; Splicing factor; Genetic disease; Virus; Cell line; Gene; Digestive diseases; Genetics; Mutation; Cystic fibrosis transmembrane conductance regulator; Pancreatic disease
• ISSN: 0964-6906; 1460-2083; 1460-2083
• DOI: 10.1093/hmg/9.12.1771

Variable levels of aberrantly spliced cystic fibrosis transmembrane conductance regulator (CFTR ) transcripts were suggested to correlate with variable cystic fibrosis (CF) severity. We studied the effect of the cellular splicing factors, hnRNP A1 and ASF/SF2, and their adenoviral analogues, E4-ORF6 and E4-ORF3, that promote exon skipping and/or exon inclusion, on the splicing pattern of the CFTR mutation 3849+10kb C-->T and the 5T allele. These mutations can lead to cryptic exon inclusion and exon skipping, respectively. Overexpression of the cellular factors promoted exon skipping of pre-mRNA transcribed from minigenes carrying the mutation (p5T or p3849M). This led to a substantial decrease in the level of correctly spliced mRNA transcribed from p5T and generated correctly spliced mRNA transcribed from p3849M that was not found without overexpression of the factors. The viral factor, E4-ORF3, promoted exon inclusion and led to a substantial increase of the correctly spliced mRNA transcribed from the p5T. The factor, E4-ORF6, activated exon skipping and generated correctly spliced mRNA transcribed from p3849M. Thus, overexpression of alternative splicing factors can modulate the splicing pattern of CFTR alleles carrying splicing mutations. These results are important for understanding the mechanism underlying phenotypic variability in CF and other genetic diseases.