| 2013 |
PHRF1 functions as an E3 ubiquitin ligase that ubiquitinates TGIF (TG-interacting factor) at lysine 130, driving its proteasomal degradation. This TGIF degradation releases cPML to redistribute into the cytoplasm, where cPML associates with SARA and coordinates Smad2 phosphorylation/activation by the TGF-β receptor, thereby promoting TGF-β cytostatic signaling. |
Ubiquitination assay, immunoprecipitation, site-directed mutagenesis (K130 of TGIF), cell fractionation, tumor xenograft reconstitution |
Cell reports |
High |
23911286
|
| 2015 |
PHRF1 localizes rapidly to DNA damage lesions upon genotoxic insults. Its PHD domain binds constitutively to di- and trimethylated histone H3 lysine 36 (H3K36me2/me3). The SDTE motif (S915DT917E) is required for interaction with NBS1. Both the PHD domain and SDTE motif are required for PHRF1's ability to promote non-homologous end-joining (NHEJ). PHRF1 also mediates PARP1 polyubiquitination leading to its proteasomal degradation. |
Immunoprecipitation, peptide pull-down assay, plasmid-based NHEJ reporter assay, site-directed mutagenesis (SDTEADAE), overexpression/ablation in H1299 reporter cells, live-cell localization after DNA damage |
Cell death & disease |
High |
25855964
|
| 2015 |
PML-RARα disrupts the PHRF1 tumor suppressor network by competing with PHRF1 for binding to TGIF, thereby blocking PHRF1-mediated TGIF ubiquitination and degradation. This results in cPML sequestration and inactivation, suppressing TGF-β cytostatic signaling and promoting acute promyelocytic leukemia (APL). Enforcing PHRF1 activity restores TGF-β signaling in human blasts and suppresses APL formation in a mouse model. |
Co-immunoprecipitation (competition binding), TGIF ubiquitination assay, TGF-β reporter assay, mouse APL model with PHRF1 reconstitution |
Cell reports |
High |
25683711
|
| 2020 |
PHRF1 promotes lung cancer cell migration and invasion by modulating ZEB1 transcription. PHRF1 associates with the phosphorylated C-terminal repeat domain (CTD) of Rpb1 (large subunit of RNA Pol II) via its C-terminal SRI domain. Chromatin immunoprecipitation showed PHRF1 binds the proximal region adjacent to the ZEB1 transcription start site. SRI domain deletion abolishes both Rpb1 association and ZEB1 upregulation. |
Co-immunoprecipitation, chromatin immunoprecipitation (ChIP), SRI domain deletion mutagenesis, transwell invasion/migration assay |
PloS one |
Medium |
32730336
|
| 2023 |
In colorectal cancer HCT116-p53-/- cells, PHRF1 promotes invasion via its C-terminal SRI domain by modulating SOX4 expression. PHRF1 knockout reduces SOX4 levels and impairs invasion; reintroduction of SOX4 partially restores invasive capability. ZEB1 expression was not affected (negative finding for ZEB1 in this context). |
CRISPR-Cas9 PHRF1 knockout, SRI domain deletion, transwell invasion assay, SOX4 rescue experiment, expression profiling |
Anticancer research |
Medium |
38030167
|
| 2023 |
PHRF1 promotes IgA class switch recombination in CH12F3-2A B cells. PHRF1 knockout reduces IgA production and decreases levels of PARP1, NELF-A, and NELF-D. Reintroduction of PARP1 partially restores IgA switching in PHRF1 knockout cells. However, IgA and other Ig class switches were not significantly decreased in PHRF1-deficient primary splenic B cells from CD19-Cre mice (negative finding in primary cells). |
CRISPR-Cas9 knockout, shRNA silencing, flow cytometry for IgA, PARP1 rescue, CD19-Cre conditional knockout mice |
PloS one |
Medium |
37540725
|
| 2025 |
PHRF1 mono-ubiquitinates TopBP1 at lysine 73, which enhances the TopBP1-ATR interaction and promotes ATR activation during replication stress. PHRF1 is recruited to DNA lesions in a manner dependent on its PHD domain and histone methylation. PHRF1 depletion disrupts ATR activation and sensitizes cells to replication stress agents. Conditional knockout of Phrf1 in mice causes early lethality with impaired ATR-Chk1 axis signaling. |
Co-immunoprecipitation, in vitro ubiquitination assay, site-directed mutagenesis (K73 of TopBP1), ATR/Chk1 activation assays, conditional mouse knockout, replication stress sensitivity assays |
Nucleic acids research |
High |
40052822
|
| 2025 |
The PHD finger of PHRF1 robustly binds the N-terminal region of histone H3. A cancer-associated P221L mutation in the PHD finger abolishes histone H3 interaction and fails to rescue defective DNA damage response (DDR) in PHRF1 knockout cells, demonstrating that H3 binding by the PHD finger is required for proper DDR. PHRF1 also regulates transcription and RNA splicing as shown by RNA-seq and proteomics. |
Biochemical binding assays, site-directed mutagenesis (P221L), PHRF1 knockout cells, DDR functional rescue assay, RNA-seq, proteomics |
Nucleic acids research |
High |
40671529
|
| 2025 |
PHRF1 acts as an E3 ubiquitin ligase for p53, targeting it for ubiquitin-proteasome-mediated degradation. In XPC-deficient bladder cancer cells, KDM4A overactivation suppresses PHRF1 expression, leading to nuclear p53 accumulation and autophagy induction in response to cisplatin. Under cisplatin-induced DNA damage where MDM2 function is impaired, PHRF1 retains its E3 ligase activity toward p53. |
Western blot (p53 accumulation), ubiquitination assay, KDM4A inhibitor treatment, mouse xenograft model, XPC knockdown/knockout |
Advanced science |
Medium |
41215711
|
| 2016 |
Overexpression of PHRF1 in H1299 non-small cell lung cancer cells inhibits proliferation and tumorigenicity, arrests cell cycle in G1 phase, decreases TGIF and c-Myc protein levels, and increases p21 protein levels, consistent with its role in TGF-β cytostatic signaling. |
Overexpression in H1299 cells, flow cytometry cell cycle analysis, soft agar assay, tumor xenograft, Western blot |
Oncotarget |
Medium |
27608840
|