TDP-43 binds heterogeneous nuclear ribonucleoprotein A/B through its C-terminal tail: an important region for the inhibition of cystic fibrosis transmembrane conductance regulator exon 9 splicing.
TDP-43 is a highly conserved nuclear factor of yet unknown function that binds to ug-repeated sequences and is responsible for cystic fibrosis transmembrane conductance regulator exon 9 splicing inhibition. We have analyzed TDP-43 interactions with other splicing factors and identified the critical regions for the protein/protein recognition events that determine this biological function. We show here that the C-terminal region of TDP-43 is capable of binding directly to several proteins of the heterogeneous nuclear ribonucleoprotein (hnRNP) family with well known splicing inhibitory activity, in particular, hnRNP A2/B1 and hnRNP A1. Mutational analysis showed that TDP-43 proteins lacking the C-terminal region could not inhibit splicing probably because they were unable to form the hnRNP-rich complex involved in splicing inhibition. Finally, through splicing complex analysis, we show that splicing inhibition mediated by TDP-43 occurs at the earliest stages of spliceosomal assembly.
Buratti
Emanuele
E
International Centre for Genetic Engineering and Biotechnology, Trieste, Italy.
Brindisi
Antonia
A
Giombi
Maurizio
M
Tisminetzky
Sergio
S
Ayala
Youhna M
YM
Baralle
Francisco E
FE
D017398:Alternative Splicing / Q000235:genetics; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D005091:Exons / Q000235:genetics*; D006367:HeLa Cells; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B / Q000378:metabolism*; D006801:Humans; D005810:Multigene Family; D011485:Protein Binding; D012326:RNA Splicing / Q000235:genetics*
D004268:DNA-Binding Proteins; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D019005:Cystic Fibrosis Transmembrane Conductance Regulator