Disease mechanism for retinitis pigmentosa (RP11) caused by mutations in the splicing factor gene PRPF31.
This study investigates the functional consequences of two mutations, A194E and A216P, in the splicing factor gene PRPF31 linked to autosomal dominant retinitis pigmentosa (RP11). Using a yeast complementation assay, we demonstrate that introduction of the human A216P mutation into the yeast orthologue PRP31p results in only partial rescue of growth at the restrictive temperature, indicating that splicing function is not fully restored. An in vivo assay of splicing function in human cells using a bovine rod opsin splicing template did not detect any defect in splicing efficiency or accuracy attributable to either mutation, suggesting that neither has a dominant negative effect on splicing. However, western analysis and immunofluorescence microscopy of mammalian cells transfected with PRPF31 revealed that both mutations substantially hinder translocation of the protein into the nucleus. The overall effect may thus be an insufficiency in splicing function, which is revealed only under conditions of elevated splicing demand. With the need to replenish disc proteins on a daily basis, such conditions will exist in rod photoreceptors and this may underlie the disease pathology.
Deery
Evelyne C
EC
School of Biological Sciences, Queen Mary, University of London, London E1 4NS, UK.
Vithana
Eranga N
EN
Newbold
Richard J
RJ
Gallon
Victoria A
VA
Bhattacharya
Shomi S
SS
Warren
Martin J
MJ
Hunt
David M
DM
Wilkie
Susan E
SE
D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D005136:Eye Proteins / Q000096:biosynthesis / Q000235:genetics*; D005816:Genetic Complementation Test; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D020125:Mutation, Missense; D012174:Retinitis Pigmentosa / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D014162:Transfection
D005136:Eye Proteins; C454222:PRPF31 protein, human; D029701:Saccharomyces cerevisiae Proteins