| 2024 |
Crystal structure of the human CTDNEP1-NEP1R1 complex reveals that NEP1R1 acts as an activating regulatory subunit that binds CTDNEP1 at a site distant from the active site to allosterically stabilize and activate CTDNEP1 phosphatase activity; substrate recognition is facilitated by a conserved Arg residue in CTDNEP1 that binds and orients substrate peptide in the active site; knockdown of NEP1R1 generates identical ER expansion phenotypes to loss of CTDNEP1, establishing them as a conserved complex that restricts ER membrane expansion. |
X-ray crystallography of CTDNEP1-NEP1R1 complex bound to pseudosubstrate peptide, in vitro phosphatase activity assays, mammalian cell knockdown with ER morphology readout |
Proceedings of the National Academy of Sciences of the United States of America |
High |
38776370
|
| 2023 |
Crystal structure of the human CTDNEP1-NEP1R1 complex (preprint version confirming peer-reviewed findings): NEP1R1 allosterically activates CTDNEP1 by binding distant from the active site; conserved Arg in CTDNEP1 orients substrate in active site; CTDNEP1 and NEP1R1 co-knockdown generate identical ER expansion phenotypes. |
X-ray crystallography, in vitro phosphatase assay, cell knockdown with ER morphology readout |
bioRxivpreprint |
High |
38045299
|
| 2024 |
CTDNEP1-NEP1R1, together with scaffold protein MAN1 at the inner nuclear membrane, forms a complex that dephosphorylates receptor-regulated SMADs (R-SMADs) in the nucleus to terminate TGF-β superfamily signaling; MAN1 binds independently to the CTDNEP1-NEP1R1 phosphatase and to R-SMADs to promote their inactivation; disruption of this complex causes nuclear accumulation of phosphorylated R-SMADs and aberrant signaling even without TGF-β ligand. |
Domain mapping, structural prediction, mutagenesis, co-immunoprecipitation, phosphoproteomics, cell-based TGF-β signaling assays with R-SMAD dephosphorylation readout |
bioRxivpreprint |
High |
bio_10.1101_2024.09.23.614427
|
| 2011 |
Human CTDNEP1/Dullard is a phosphoserine phosphatase that shows substrate specificity for the insulin-dependent phosphorylation site (Ser106) of lipin1, with a kcat/Km of 2.9×10^4 M−1 s−1, and does not require an adaptor protein for this activity. |
Steady-state kinetic analysis using phosphoserine-bearing nonapeptides corresponding to lipin1 phosphorylation sites |
Biochemistry |
High |
21413788
|
| 2006 |
Xenopus Dullard (ortholog of CTDNEP1) promotes ubiquitin-mediated proteasomal degradation of BMP receptors; it preferentially complexes with BMPRII and partially colocalizes with caveolin-1-positive compartments, suggesting degradation via the lipid raft-caveolar pathway; it also associates with BMP type I receptors and represses BMP-dependent phosphorylation of type I receptors; phosphatase activity is required for BMPR degradation and neural induction. |
Co-immunoprecipitation, colocalization with caveolin-1, phosphatase-dead mutant analysis, Xenopus morpholino knockdown with neural marker gene readout |
Developmental cell |
High |
17141153
|
| 2016 |
Drosophila Dullard (ortholog of CTDNEP1) physically interacts with phosphorylated Mad (R-Smad) via co-immunoprecipitation and dephosphorylates both C-terminal and linker phosphorylations of Mad to terminate BMP signaling; phosphatase-domain mutation abolishes dephosphorylation but not binding; Dullard acts as an alternative to proteasomal degradation for terminating BMP signaling. |
Co-immunoprecipitation, hypomorphic allele and RNAi knockdown with pMad western blot readout, Dullard overexpression, phosphatase-domain point mutation |
Scientific reports |
High |
27578171
|
| 2021 |
CTDNEP1/Dullard, a nuclear envelope phosphatase, directly interacts with the actin regulator Eps8L2; this interaction regulates formation and thickness of dorsal actin cables required for TAN line engagement and nuclear movement during cell migration; loss of either protein impairs nuclear positioning and cell migration. |
Co-immunoprecipitation/direct interaction assay, siRNA knockdown with nuclear positioning and cell migration readouts, actin cable imaging |
Current biology : CB |
Medium |
33567288
|
| 2023 |
CTDNEP1 deficiency stabilizes and activates MYC by elevating MYC Ser62 phosphorylation, and triggers chromosomal instability; phosphoproteomics reveals CTDNEP1 post-translationally modulates activities of chromosome segregation and mitotic checkpoint regulators including TOP2A and CHEK1. |
Ctdnep1 mouse knockout tumor model, phosphoproteomics, MYC phosphorylation (pSer62) western blot, chromosomal instability assays, co-targeting MYC and CHEK1 in tumor models |
Nature communications |
High |
36765089
|
| 2013 |
Mouse Dullard/Ctdnep1 deletion in metanephric mesenchyme leads to massive nephron apoptosis associated with upregulation of phospho-Smad1/5/8, consistent with cell-autonomous inhibition of BMP signaling; BMP receptor kinase inhibitor LDN-193189 partially rescues the nephron defects, placing Dullard upstream of BMP receptor activity in kidney maintenance. |
Conditional knockout mouse, phospho-Smad1/5/8 immunostaining, pharmacological rescue with BMP receptor inhibitor LDN-193189 |
Nature communications |
High |
23360989
|
| 2015 |
Dullard/Ctdnep1 suppresses TGF-β signaling during endochondral ossification; Dullard deficiency upregulates phospho-Smad2/3 and total Smad2/3 protein levels without increasing Smad2/3 mRNA, suggesting Dullard affects Smad2/3 protein stability; skeletal defects in Dullard-deficient mice are rescued by TGF-β type I receptor kinase blocker LY-364947. |
Conditional knockout mouse (Prx1-Cre), micromass culture, phospho-Smad2/3 and total Smad2/3 western blot, pharmacological rescue with LY-364947 in vivo |
Journal of bone and mineral research |
High |
25155999
|
| 2013 |
Mouse Dullard/Ctdnep1 loss impairs primordial germ cell formation by reducing WNT/β-catenin signaling and Dishevelled 2 (Dvl2) protein levels; compound heterozygosity with Wnt3 has synergistic effects on PGC reduction, placing Dullard as a positive modulator of WNT signaling in germ cell specification. |
Conditional mouse knockout, compound heterozygote genetic epistasis with Wnt3, β-catenin reporter assay, Dvl2 western blot |
PloS one |
Medium |
23469192
|
| 2020 |
Dullard, acting as a nuclear phosphatase, tunes BMP signaling amplitude during cardiac outflow tract development; it maintains neural crest cells in a mesenchymal state by attenuating Sema3c expression and promoting Twist1 expression; loss of Dullard leads to premature NCC condensation and tetralogy of Fallot-like defects, with elevated pSmad1/5/8. |
Conditional mouse knockout (NCC-specific), BMP signaling reporter, pSmad1/5/8 immunostaining, gene expression analysis of Sema3c and Twist1 |
eLife |
High |
32105214
|
| 2011 |
Drosophila Dullard (ddd) genetically interacts with BMP signaling pathway components to regulate wing vein formation; manipulation of ddd expression alters p-Mad levels; Dullard overexpression mislocalizes nuclear import machinery components Importin-β and RanGAP and alters membrane lipid staining, suggesting Dullard regulates nuclear envelope/membrane lipid homeostasis to affect BMP signaling. |
Genetic interaction screen (double mutant wing vein phenotype), pMad western blot, Importin-β and RanGAP localization by immunofluorescence, membrane lipid staining |
Development, growth & differentiation |
Medium |
21790556
|
| 2024 |
Ctdnep1 negatively regulates RANKL-induced osteoclast differentiation; Ctdnep1 knockdown increases phosphorylation of RANKL signaling components and elevates Nfatc1 protein even without RANKL stimulation, and enhances calcium-resorbing activity. |
siRNA knockdown in RAW264.7 cells, TRAP staining for osteoclast numbers, osteoclast marker gene qPCR, western blot for pRANKL signaling components and Nfatc1, calcium resorption assay |
Biochemical and biophysical research communications |
Medium |
38749090
|
| 2018 |
Dullard/Ctdnep1 suppresses BMP signaling in ovarian granulosa cells; conditional deletion leads to hemorrhagic ovarian cysts and upregulation of BMP-inducible inhibitory Smads (Smad6/Smad7); pharmacological rescue with BMP receptor inhibitor LDN-193189 confirmed the mechanism is through BMP signaling. |
Conditional knockout mouse (Col1a1-Cre and Rosa26-CreER), Smad6/7 gene expression, BMP receptor inhibitor rescue |
Genes to cells |
Medium |
29521016
|