Pre-mRNA 3'-end processing, the process through which almost all eukaryotic 
mRNAs acquire a poly(A) tail is generally inhibited during the cellular DNA 
damage response leading to a profound impact on the level of protein expression 
since unprocessed transcripts at the 3'-end will be degraded or unable to be 
transported to the cytoplasm. However, a compensatory mechanism involving the 
binding of the hnRNP H/F family of RNA binding proteins to an RNA G-quadruplex 
(G4) structure located in the vicinity of a polyadenylation site has previously 
been described to allow the transcript encoding the p53 tumour suppressor 
protein to be properly processed during DNA damage and to provide the cells with 
a way to react to DNA damage. Here we report that the DEAH (Asp-Glu-Ala-His) box 
RNA helicase DHX36/RHAU/G4R1, which specifically binds to and resolves 
parallel-stranded G4, is necessary to maintain p53 pre-mRNA 3'-end processing 
following UV-induced DNA damage. DHX36 binds to the p53 RNA G4, while mutation 
of the G4 impairs the ability of DHX36 to maintain pre-mRNA 3'-end processing. 
Stabilization of the p53 RNA G4 with two different G4 ligands (PNADOTASQ and 
PhenDC3), which is expected from previous studies to prevent DHX36 from binding 
and unwinding G4s, also impairs p53 pre-mRNA 3'-end processing following UV. Our 
work identifies DHX36 as a new actor in the compensatory mechanisms that are in 
place to ensure that the mRNAs encoding p53 are still processed following UV.