Reactome: A Curated Pathway Database

PARP1 ADP-ribosylates SMAD3 and SMAD4 (R-HSA-2187325) [Homo sapiens]


PARP1 ADP-ribosylates SMAD3 and SMAD4 in SMAD2/3:SMAD4 heterotrimer. ADP-ribosyl group is attached to glutamic acid residues E50 and E52 of SMAD3 and unknown amino acid residues of SMAD4. ADP-ribose monomer attached to SMAD3 and SMAD4 is subsequently extended to poly (ADP-ribosyl) chains (i.e. PAR chains) by PARP1, which is not shown here. ADP-ribosylation (PARylation) of SMAD3 and SMAD4 by PARP1 inhibits binding of SMAD2/3:SMAD4 heterotrimers to SMAD binding elements (SBEs) in promoters of SMAD-target genes.

Additional Information
Compartment nucleoplasm
Catalyst Activity
PhysicalEntity Activity Active Units
p-2S-SMAD2/3:SMAD4:PARP1 NAD+ ADP-ribosyltransferase activity (0003950)
Literature References
pubMedId Title Journal Year
21095583 PARP-1 attenuates Smad-mediated transcription Mol Cell 2010