Promoter architecture modulates CFTR exon 9 skipping.
Using hybrid minigene experiments, we have investigated the role of the promoter architecture on the regulation of two alternative spliced exons, cystic fibrosis transmembrane regulator (CFTR) exon 9 and fibronectin extra domain-A (EDB). A specific alternative splicing pattern corresponded to each analyzed promoter. Promoter-dependent sensitivity to cotransfected regulatory splicing factor SF2/ASF was observed only for the CFTR exon 9, whereas that of the EDB was refractory to promoter-mediated regulation. Deletion in the CFTR minigene of the downstream intronic splicing silencer element binding SF2/ASF abolished the specific promoter-mediated response to this splicing factor. A systematic analysis of the regulatory cis-acting elements showed that in the presence of suboptimal splice sites or by deletion of exonic enhancer elements the promoter-dependent sensitivity to splicing factor-mediated inhibition was lost. However, the basal regulatory effect of each promoter was preserved. The complex relationships between the promoter-dependent sensitivity to SF2 modulated by the exon 9 definition suggest a kinetic model of promoter-dependent alternative splicing regulation that possibly involves differential RNA polymerase II elongation.
Pagani
Franco
F
International Centre for Genetic Engineering and Biotechnology, Padriciano 99, Trieste 34012, Italy.
Stuani
Cristiana
C
Zuccato
Elisabetta
E
Kornblihtt
Alberto R
AR
Baralle
Francisco E
FE
D017398:Alternative Splicing; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D005091:Exons; D007438:Introns; D011401:Promoter Regions, Genetic
D019005:Cystic Fibrosis Transmembrane Conductance Regulator