| 2001 |
FZR1 (Fzr/Cdh1) activates the APC/C to ubiquitinate and degrade human securin/PTTG in vitro. Securin degradation is mediated by both an RXXL destruction box and a KEN box; mutation of both sequences together is required to prevent ubiquitination and degradation. |
In vitro APC/C ubiquitination assay; destruction box/KEN box mutagenesis; cell-based expression of non-degradable securin mutant |
The EMBO journal |
High |
11179223
|
| 2002 |
Drosophila Fzr/Cdh1 binds microtubules in vitro and associates with spindles in vivo, concentrating at centrosomes throughout the cell cycle. Fzr/Cdh1 is responsible for the second, cytoplasm-wide phase of cyclin B destruction during mitotic exit, distinct from the spindle-localized destruction driven by Fzy/Cdc20. |
Microtubule-binding assay in vitro; in vivo live imaging and immunofluorescence; destruction-box mutant cyclin B (CBTPM-GFP) degradation assay in syncytial vs. cellularized embryos |
The Journal of cell biology |
High |
12082076
|
| 2002 |
APC/C(FZR1)-dependent degradation timing is determined by the specificity of destruction box (RXXL) and KEN box motifs. KEN-box substrates are degraded exclusively by APC/C(Fzr); RXXL substrates can be degraded by both APC/C(Fzy) and APC/C(Fzr), but APC/C(Fzy)-specific RXXL degradation is highly dependent on the location of the RXXL within the substrate. APC/C(Fzr) is activated in early G1. |
Swapped destruction box mutant constructs; real-time fluorescence-based degradation assay; in vitro APC/C ubiquitination assay |
The EMBO journal |
High |
12198152
|
| 2002 |
Human Aurora-A kinase is targeted for degradation by APC/C(hCdh1/FZR1) in vivo, dependent on its destruction box, KEN box motifs, and its kinase activity. hCdc20 does not mediate Aurora-A degradation. |
Co-expression and immunoprecipitation; in vivo degradation assay with destruction box and KEN box mutants; kinase-dead mutant analysis |
FEBS letters |
Medium |
12023018
|
| 2002 |
C. elegans fzr-1 (Cdh1 homolog) functions redundantly with lin-35/Rb to control cell proliferation. Genetic epistasis places fzr-1 in a pathway regulating cyclin levels and cell cycle progression; simultaneous loss of both fzr-1 and lin-35 produces severe proliferation defects not seen with either single mutant. |
Synthetic-lethal genetic screen; double-mutant epistasis analysis in C. elegans |
Genes & development |
Medium |
11850412
|
| 2002 |
Drosophila Fzr (encoded by fzr/rap) is essential during G1 but not for mitotic exit including cyclin B degradation. FZR accumulates predominantly in the cytoplasm in Drosophila cells. Loss of fzr causes lethality corresponding to the rap locus. |
Genetic null allele characterization; fzr2 expression analysis; cell fractionation/localization; cyclin B degradation assay in fzr mutants |
Current biology : CB |
Medium |
12194827
|
| 2004 |
Mammalian Cdh1/FZR1 mediates its own degradation by activating the APC/C to ubiquitinate itself via two RXXL-type destruction boxes. In G1/G0, Cdh1 is nearly entirely APC/C-associated and present at lower levels. Addition of Cdh1 to Xenopus interphase extracts activates APC/C to degrade Cdh1 itself. |
In vitro Xenopus interphase extract degradation assay; destruction box mutagenesis; co-immunoprecipitation of Cdh1 with APC/C; Western blot cell cycle analysis |
The EMBO journal |
High |
15029244
|
| 2009 |
Loss of FZR1 in human cell lines (RNAi) and mouse embryonic fibroblasts (conditional knockout) shortens G1 phase and prolongs S phase, induces DNA-damage responses, and impairs proliferation independently of p53 status. FZR1 is not required for mitotic exit in mammalian somatic cells. |
RNAi knockdown in human cell lines; conditional gene targeting in MEFs; cell cycle analysis; DNA damage response markers |
Journal of cell science |
High |
19861496
|
| 2009 |
CDC14B phosphatase prevents meiotic resumption in mouse oocytes through FZR1 (Cdh1). Depletion of FZR1 partially restores normal meiotic timing in oocytes with excess CDC14B, placing FZR1 downstream of CDC14B in controlling APC/C-mediated cyclin B1 proteolysis and prophase I arrest. |
mRNA injection for overexpression; morpholino/siRNA depletion of FZR1 and CDC14B in mouse oocytes; epistasis analysis; localization studies |
Biology of reproduction |
Medium |
19129509
|
| 2010 |
APC/C(Fzr/Cdh1) controls peripheral glial migration in post-mitotic Drosophila neurons by regulating the axonal distribution of the cell adhesion molecule Fasciclin2 (Fas2). Fzr/Cdh1 establishes a graded axonal Fas2 distribution, and axonal Fas2 interacts homophilically with a glial isoform to guide glial migration. |
Genetic loss-of-function (fzr mutants); immunofluorescence; in vivo imaging of glial migration; epistasis with fas2 alleles |
Nature neuroscience |
Medium |
20890296
|
| 2011 |
APC/C(FZR1) activity in mouse oocytes is required to repress cyclin B1 levels during prophase I arrest, maintaining meiotic quiescence. In oocyte-specific Fzr1 knockout mice, cyclin B1 levels are ~5-fold elevated, prophase I/GV arrest is compromised, and cyclin B1 knockdown in Fzr1-null oocytes partially rescues the timing of meiotic resumption. |
Oocyte-specific conditional knockout; Western blot; cyclin B1 knockdown rescue experiment; in vitro oocyte maturation assay |
Development (Cambridge, England) |
High |
21270054
|
| 2012 |
FZR1 controls the timing of bipolar meiotic spindle assembly in mouse oocytes, thereby regulating when the spindle assembly checkpoint (SAC) is satisfied and APC/C(CDC20) becomes active. Loss of FZR1 accelerates spindle assembly, leading to premature bivalent attachment, poor chromosome congression, and 25% nondisjunction. FZR1 loss does not abrogate SAC functionality. |
Oocyte-specific Fzr1 conditional knockout; live imaging; SAC marker (MAD2) localization; spindle assembly timing assay |
Molecular biology of the cell |
High |
22918942
|
| 2012 |
Maternal and zygotic FZR1 is required for syngamy (establishment of a single spindle from two pronuclei) and maintenance of genomic integrity during the first mitotic divisions of mouse embryos. Absence of both maternal and paternal FZR1 leads to formation of two independent spindles after pronuclear fusion, binucleate 2-cell embryos, and embryonic arrest. |
Oocyte-specific knockout (maternal FZR1 depleted) crossed to zygotic null; γ-H2AX foci imaging; live imaging of spindle formation |
Journal of cell science |
Medium |
23097041
|
| 2015 |
FZR1 is a substrate of CDK4/6-cyclin D kinase. CDK-4/CYD-1 phosphorylates specific residues in the FZR-1 amino terminus (C. elegans), resembling inactivating phosphorylations of human FZR1. Simultaneous knockdown of Rb and FZR1 in human breast cancer cells synergistically bypasses cell division arrest induced by the CDK4/6-specific inhibitor PD-0332991. |
Unbiased genetic screen in C. elegans; phosphorylation site mapping; RNAi double knockdown in human breast cancer cells; CDK4/6 inhibitor rescue assay |
Nature communications |
High |
25562820
|
| 2016 |
Drosophila Fzr/Cdh1 localizes to centrioles during interphase via direct interaction with the centrosome component Spd2. This centrosomal localization is essential for optimal APC/C activation toward its centrosomal substrate Aurora A. Spd2 is itself a novel APC/C(Fzr) substrate. |
Co-immunoprecipitation; Spd2 mutants unable to bind Fzr; in vivo localization (immunofluorescence); APC/C activity assays toward Aurora A substrate |
Nature communications |
High |
27558644
|
| 2016 |
APC/C(FZR1) ubiquitinates Topoisomerase IIα (TOPIIα) for degradation. Knockdown of FZR1 in multiple myeloma cells reduces viability and induces growth arrest, with accumulation of TOPIIα as a substrate readout. |
siRNA knockdown; Western blot for substrate accumulation (TOPIIα); cell viability assay; APC/C inhibitor (proTAME) |
Oncotarget |
Medium |
27655696
|
| 2016 |
APC/C(Fzr/Cdh1) negatively regulates Nek2 kinase (a direct substrate targeted for ubiquitination and degradation), which in turn negatively regulates the PCP factor Dishevelled. Loss of APC/C function in Drosophila leads to reduced Dishevelled levels through Nek2 accumulation, establishing a post-mitotic role for APC/C(Fzr) in epithelial planar cell polarity. |
Genetic loss-of-function; epistasis analysis; in vivo substrate degradation assay; immunofluorescence |
Developmental cell |
Medium |
28041906
|
| 2017 |
FZR1 inhibits BRAF through two distinct mechanisms: (1) APC/C(FZR1) ubiquitinates BRAF for proteasomal degradation in primary cells; (2) APC/C-free FZR1 suppresses BRAF by disrupting BRAF dimerization. ERK and CYCLIN D1/CDK4 phosphorylate FZR1 to inhibit APC/C(FZR1) activity. CDK4 and/or BRAF/MEK inhibitors restore APC/C(FZR1) activity. |
Co-immunoprecipitation; ubiquitination assays; FZR1 phosphorylation site identification; in vivo mouse model (Fzr1 ablation with Pten loss); pharmacological inhibitor treatments |
Cancer discovery |
High |
28174173
|
| 2018 |
PRL-3 phosphatase dephosphorylates FZR1, which activates the APC/C(FZR1) complex, leading to enhanced AURKA ubiquitination and degradation. PRL-3 physically interacts with both AURKA and FZR1. |
Co-immunoprecipitation; ubiquitination assay; phosphatase-dead PRL-3 mutant; Western blot for AURKA levels upon PRL-3/FZR1 manipulation |
Cancer research |
Medium |
30498084
|
| 2020 |
CDK-mediated phosphorylation of FZR1 is required for entry into meiosis II in mouse male germ cells in vivo. Non-phosphorylatable FZR1 knock-in mice show normal somatic cell cycles but male infertility due to failure to enter meiosis II and form spermatids, associated with dysregulated APC/C activity. |
Non-phosphorylatable knock-in mouse model (CDK-site substitution); testis histology; germ cell meiosis progression analysis; Western blot for FZR1 substrates |
Scientific reports |
High |
32572094
|
| 2020 |
Fzr/Cdh1 interacts with chromatin-associated histone H2B to enhance H2B ubiquitination at the Myc promoter, promoting Myc transcription, which in turn drives MCM6 expression to promote DNA replication during endoreplication. This non-APC/C transcriptional cascade is conserved between Drosophila and mammalian cells. |
Co-immunoprecipitation; ChIP; promoter reporter assays; genetic knockdown of fzr; conservation validated in mammalian cells |
Nucleic acids research |
Medium |
32182338
|
| 2021 |
FZR1 ubiquitinates RUNX1 at lysine 125, targeting it for proteasomal degradation. FZR1 insufficiency leads to RUNX1 accumulation, which disrupts HSC quiescence and self-renewal in aplastic anemia. |
Ubiquitination assay with K125 mutation; Fzr1 heterozygous knockout mouse models; RUNX1 knockdown rescue in Fzr1+/- HSCs; in vivo repopulation assay |
Leukemia |
Medium |
34635784
|
| 2021 |
FZR1 interacts with pRB via an LxCxD motif; the cysteine residue in this motif is critical for direct binding to pRB's LxCxE-binding pocket. Mutation of this cysteine disrupts pRB interaction but not FZR1 association with core APC/C. FZR1 LxCxD mutant cells show accumulation of SKP2 and PLK1, downregulation of p27Kip1 and p21Cip1, and premature S-phase entry. |
Point mutagenesis; in vitro binding assay; competition with HPV E7; co-immunoprecipitation; cell cycle analysis |
Experimental cell research |
Medium |
33971196
|
| 2022 |
The reported C-terminal D-box of Aurora A (AURKA) does not function as a degron for APC/C(FZR1)-dependent degradation; instead, it mediates essential structural features of the protein. The N-terminal A-box (containing the QRVL motif, a phospho-regulated D-box) in the intrinsically disordered region of AURKA is sufficient to confer FZR1-dependent mitotic degradation. |
In cellulo degradation assays with AURKA deletion/mutation constructs; in silico D-box prediction; cell-based FZR1-dependent degradation assay with N-terminal fragment |
Life science alliance |
Medium |
36450448
|
| 2017 |
APC/C(FZR-1) in C. elegans regulates centrosome duplication by controlling SAS-5 protein levels. FZR-1 directly recognizes the KEN-box motif of SAS-5 to promote its degradation. FZR-1 associates with centrosomes and is enriched at nuclei during mitotic cell division in early embryos. |
fzr-1 loss-of-function genetics; immunofluorescence for FZR-1 localization; centrosome duplication assay; KEN-box mutant analysis of SAS-5 |
G3 (Bethesda, Md.) |
Medium |
29030390
|
| 2025 |
In C. elegans, APC/C(FZR-1) facilitates the degradation of chromatin regulators MES-4 and MES-3 when germline stem cells transition toward oocyte differentiation. Notch signaling from the distal tip cell restricts APC/C(FZR-1) activity to allow MES-3 and MES-4 accumulation in GSCs and maintain stemness. |
Genetic loss-of-function of fzr-1 and APC/C subunits; protein level measurements by immunofluorescence; epistasis with Notch pathway mutants |
Science advances |
Medium |
40446035
|
| 2025 |
SPD-2 (homolog of human CEP192) is a substrate of APC/C(FZR-1) in C. elegans embryos. SPD-2 physically associates with FZR-1 in vivo. Three distinct D-box motifs in SPD-2 contribute differentially to degradation and centrosomal localization: D-box3 mutation stabilizes centrosomal SPD-2 and restores centrosome duplication in zyg-1 mutants, while D-box1 mutation reduces centrosomal SPD-2 and worsens duplication defects. |
Co-immunoprecipitation (FZR-1 and SPD-2 in vivo); D-box site mutagenesis; centrosome duplication rescue assay; immunofluorescence |
bioRxivpreprint |
Medium |
41278915
|
| 2025 |
FZR1/Cdh1 promotes TRAF3 and TRAF6 autoubiquitination independently of the APC/C, attenuates MAVS binding to PFKFB3, promotes MAVS aggregation, and thereby activates IRF3 and NF-κB to drive type I interferon and proinflammatory cytokine production during RNA virus infection. This antiviral function is enhanced by m6A-mediated increase in FZR1 translation upon VSV infection. |
Co-immunoprecipitation; ubiquitination assay (TRAF3/6 autoubiquitination); MAVS aggregation assay; FZR1 knockout cells and mice; pharmacological FZR1 inhibition |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
41805567
|
| 2025 |
USP8 deubiquitinase interacts with FZR1 (Fzr) and deubiquitinates it to promote its stabilization, which is required for endoreplication in Drosophila salivary gland and Bombyx silk gland. Hsp70 mediates proper folding of Fzr and increases the Fzr-USP8 interaction, thereby enhancing Fzr deubiquitination. |
Co-immunoprecipitation; deubiquitination assay; genetic depletion of USP8 and Hsp70; endoreplication assay |
Science advances |
Medium |
40106570
|
| 2023 |
GEMIN5, an m6A reader protein, binds m6A-modified FZR1 mRNA and recruits the eIF3 translation initiation complex, accelerating FZR1 protein translation. Elevated FZR1 protein maintains G0-G1 quiescence and suppresses gemcitabine sensitivity in pancreatic cancer cells. |
m6A profiling; GEMIN5-FZR1 mRNA Co-IP; eIF3 complex co-immunoprecipitation; FZR1 knockdown; cell cycle analysis |
Cancer research |
Medium |
37326469
|
| 2025 |
FZR1 ubiquitinates ANLN (Anillin) for degradation. CCNE1 (Cyclin E1) competes with FZR1-mediated ANLN ubiquitination by binding ANLN and stabilizing it, promoting TNBC stemness and progression. Mutation of the ANLN ubiquitination site abolishes CCNE1's regulatory effect. |
Co-immunoprecipitation; ubiquitination assay; ANLN ubiquitination site mutagenesis; CCNE1 knockdown/overexpression; in vitro and in vivo functional assays |
Cell death discovery |
Medium |
40346052
|
| 2026 |
FZR1 ubiquitinates c-MYC for proteasomal degradation. DSN1 competes with c-MYC for FZR1 binding, thereby attenuating c-MYC ubiquitination and stabilizing c-MYC to promote colorectal cancer metastasis. |
Co-immunoprecipitation; ubiquitination assay; cycloheximide chase; proteasome inhibition; rescue experiment with c-MYC overexpression |
Experimental cell research |
Medium |
41713835
|