Small nuclear U1-RNAs (snRNAs), the spliceosome components selectively recognizing donor splice sites (5'ss), were engineered to restore correct mRNA processing in a cellular model of severe coagulation factor VII (FVII) deficiency, caused by the IVS7 9726+5g/a change. Three U1-snRNAs, complementary to the mutated 5’ss (U1+5a) or to neighbouring sequences, were expressed with FVII minigenes in a hepatoma cell line. The U1-snRNAs reduced from 80% to 40% the exon 7 skipping, thus increasing exon definition. The U1+5a construct also dramatically increased recognition of the correct 5'ss over the 37bp-downstream cryptic site preferentially activated by the mutation, thus inducing appreciable synthesis of normal transcripts (from barely detectable to 50%). This effect, which was dose-dependent, clearly demonstrated that impaired recognition by the U1-snRNA was the mechanism responsible for FVII deficiency. These findings suggest compensatory U1-snRNAs as therapeutic tools in coagulation factor deficiencies caused by mutations at 5'ss, a frequent cause of severe defects.

U1snRNA-mediated rescue of mRNA processing in severe factor VII deficiency

PINOTTI, Mirko;RIZZOTTO, Lara;BALESTRA, Dario;CAVALLARI, Nicola;MARCHETTI, Giovanna;BERNARDI, Francesco;
2008

Abstract

Small nuclear U1-RNAs (snRNAs), the spliceosome components selectively recognizing donor splice sites (5'ss), were engineered to restore correct mRNA processing in a cellular model of severe coagulation factor VII (FVII) deficiency, caused by the IVS7 9726+5g/a change. Three U1-snRNAs, complementary to the mutated 5’ss (U1+5a) or to neighbouring sequences, were expressed with FVII minigenes in a hepatoma cell line. The U1-snRNAs reduced from 80% to 40% the exon 7 skipping, thus increasing exon definition. The U1+5a construct also dramatically increased recognition of the correct 5'ss over the 37bp-downstream cryptic site preferentially activated by the mutation, thus inducing appreciable synthesis of normal transcripts (from barely detectable to 50%). This effect, which was dose-dependent, clearly demonstrated that impaired recognition by the U1-snRNA was the mechanism responsible for FVII deficiency. These findings suggest compensatory U1-snRNAs as therapeutic tools in coagulation factor deficiencies caused by mutations at 5'ss, a frequent cause of severe defects.
Pinotti, Mirko; Rizzotto, Lara; Balestra, Dario; Marzena Anna, Lewandowska; Cavallari, Nicola; Marchetti, Giovanna; Bernardi, Francesco; Franco, Pagani
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11392/520017
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 46
  • ???jsp.display-item.citation.isi??? ND
social impact