Differential expression of RPS19 5’UTR variants implicated in Diamond-Blackfan anemia
2012 (English)Article in journal (Other academic) In press
Heterozygous mutations in the ribosomal protein (RP) S19 gene RPS19 are found in about 25% of patients with the congenital erythroblastopenia Diamond-Blackfan anemia (DBA). The RPS19 gene encodes a single RPS19 isoform from three known transcriptional start sites (TSS) with different 5’ untranslated region (UTR). The regulation of RPS19 expression is poorly understood as well as the significance of different 5’UTRs. A few rare sequence variants within the 5’UTR have also been reported in patients with DBA. We determined the transcriptional start sites (TSS) and the tissue distribution of variant 5’UTRs of RPS19. Twenty-nine novel TSS in K562 cells and testis were identified. We then analyzed the relative proportion of three selected 5’UTRs of different length on a panel of primary tissues. The shorter 5’UTR were most abundant in all tissues but with large variations in relative levels of shorter versus longer transcripts. To clarify the effect of different RPS19 5’UTRs on translation we designed and expressed constructs using three 5’UTRs of different length. The short 5’UTR(+35nt.) translate 4-6 folds more efficiently than the two longer variants with 5’UTRs of 382nt. and 467nt., respectively We also introduced DBA associated insertion (c.-149_-148insGCCA, c.-149_-148insAGCC ) and deletion (c.-144_-141delTTTC) variants in the 5’UTR. . Interestingly, the DBA associated 5’UTR sequence variants showed a 20-30% reduction in RPS19 levels when compared to the corresponding w.t. constructs. Our results indicate that the RPS19 gene has a broad range of TSS with tissue specific variations. We also show that sequence variants in the 5’UTR in some DBA patients reduce RPS19 expression with implications for the pathophysiology of the disease.
Place, publisher, year, edition, pages
Diamond-Blackfan anemai, 5'UTR, translation, RPS19, haploinsufficiency
Research subject Clinical Genetics
IdentifiersURN: urn:nbn:se:uu:diva-110063OAI: oai:DiVA.org:uu-110063DiVA: diva2:274868