A missense mutation in the APC tumor suppressor gene disrupts an ASF/SF2 splicing enhancer motif and causes pathogenic skipping of exon 14
| Autor: | Ofélia Antunes, Ana Medeira, Peter Jordan, Glória Isidro, José Silva Ramos, Vânia Gonçalves, Patrícia Theisen |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Male
Health Toxicology and Mutagenesis Adenomatous Polyposis Coli Protein Exonic splicing enhancer Mutation Missense Biology Frameshift mutation Exon Genes Reporter Genetics Humans RNA Messenger Molecular Biology Splice site mutation Serine-Arginine Splicing Factors Nuclear Proteins RNA-Binding Proteins Exons Middle Aged Splicing regulatory element Molecular biology Exon skipping Alternative Splicing Enhancer Elements Genetic Adenomatous Polyposis Coli Splicing factor binding Minigene |
| Zdroj: | Mutation research. 662(1-2) |
| ISSN: | 0027-5107 |
| Popis: | A missense mutation at codon 640 in the APC gene was identified in a familial adenomatous polyposis (FAP) patient, however, its pathological consequence remained unclear. Here we found that this missense mutation interferes at the nucleotide level with an exonic splicing regulatory element and leads to aberrant splicing of the mutant APC transcript rather than exerting its effect through the observed amino acid change. Analysis of the patient RNA revealed complete skipping of exon 14 in transcripts from the mutant APC allele, leading to a frameshift and a premature stop codon. When cloned into a splicing reporter minigene and transfected into colorectal cell lines, the exon 14 point mutation c.1918C>G (pR640G) was found sufficient to cause the observed exon skipping. Bioinformatic analysis predicted the mutation to change SRp55, hnRNP A1 or ASF/SF2 splicing factor binding sites. Using RNA interference methodology these predictions were experimentally validated and revealed that only ASF/SF2 was required for exon 14 inclusion. These research data identify APC mutation c.1918C>G (pR640G) as pathogenic and indicate a mechanism involving disruption of an ASF/SF2 exonic splicing enhancer element. The results allow genetic diagnosis of a hereditary tumour predisposition but also illustrate the need to complement in silico prediction by splicing reporter assays. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect