PARP-1 expression in the mouse is controlled by an autoregulatory loop: PARP-1 binding to an upstream S/MAR element and to a novel recognition motif in its promoter suppresses transcription.
This work identifies central components of a feedback mechanism for the expression of mouse poly(ADP-ribose) polymerase-1 (PARP-1). Using the stress-induced duplex destabilization algorithm, multiple base-unpairing regions (BURs) could be localized in the 5' region of the mouse PARP-1 gene (muPARP-1). Some of these could be identified as scaffold/matrix-attachment regions (S/MARs), suggesting an S/MAR-mediated transcriptional regulation. PARP-1 binding to the most proximal element, S/MAR 1, and to three consensus motifs, AGGCC, in its own promoter (basepairs -956 to +100), could be traced by electrophoretic mobility-shift assay. The AGGCC-complementary GGCCT motif was detected by cis-diammine-dichloro platinum cross-linking and functionally characterized by the effects of site-directed mutagenesis on its performance in wild type (PARP-1(+/+)) and PARP-1 knockout cells (PARP-1(-/-)). Mutation of the central AGGCC tract at basepairs -554 to -550 prevented PARP-1/promoter interactions, whereby muPARP-1 expression became up-regulated. Transfection of a series of reporter gene constructs with or without S/MAR 1 (basepairs -1523 to -1007) and the more distant S/MAR 2 (basepairs -8373 to -6880), into PARP-1(+/+) as well as PARP-1(-/-) cells, revealed an additional, major level of muPARP-1 promoter down-regulation, triggered by PARP-1 binding to S/MAR 1. We conclude that S/MAR 1 represents an upstream control element that acts in conjunction with the muPARP-1 promoter. These interactions are part of a negative autoregulatory loop.
Vidaković
Melita
M
Helmholtz Centre for Infection Research, Epigenetic Regulation, Braunschweig, Germany.
Gluch
Angela
A
Qiao
Junhua
J
Oumard
Andrè
A
Frisch
Matthias
M
Poznanović
Goran
G
Bode
Juergen
J
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002478:Cells, Cultured; D003432:Cross-Linking Reagents / Q000737:chemistry; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D005557:Formaldehyde / Q000737:chemistry; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012045:Regulatory Sequences, Nucleic Acid; D014158:Transcription, Genetic
D003432:Cross-Linking Reagents; D005557:Formaldehyde; D004247:DNA; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases