| 1999 |
NUBP2 (mouse Nubp2/human NUBP2) was identified as a novel eukaryotic nucleotide-binding protein related to prokaryotic MRP/MinD proteins, defining the short-form branch of the NUBP/MRP gene family. It shares conserved ATP/GTP-binding P-loop motifs and two highly conserved NUBP/MRP sequence motifs (alpha and beta) with Nubp1, but lacks the unique N-terminal four-cysteine sequence present in Nubp1/Nbp35. Mouse Nubp2 was mapped to the t-complex region of chromosome 17. |
Phylogenetic analysis, Northern blot, chromosomal mapping |
Genomics |
Medium |
10486206
|
| 2003 |
CFD1 (the yeast ortholog of NUBP2) was identified as the first cytoplasmic Fe-S cluster assembly factor in eukaryotes. A hypomorphic cfd1-1 mutation reduced cytosolic Fe-S enzyme activities (c-aconitase/IRP1 and Leu1p) by >90% without affecting mitochondrial Fe-S proteins, and Cfd1p was localized to the cytoplasm. |
Genetic screen, enzyme activity assays, EPR spectroscopy, subcellular fractionation/localization |
The EMBO journal |
High |
12970194
|
| 2007 |
Cfd1 (NUBP2 ortholog) and Nbp35 (NUBP1 ortholog) form a heterotetrameric complex in the yeast cytosol and together bind up to three [4Fe-4S] clusters—one at the N-terminus of Nbp35 and one each at a C-terminal cysteine-rich (CPXC) motif in both proteins. These labile clusters can be transferred to target Fe-S apoproteins in a Nar1- and Cia1-dependent manner, establishing the Cfd1-Nbp35 complex as a scaffold for cytosolic Fe-S protein assembly. |
In vivo and in vitro Fe-S cluster reconstitution, 55Fe radiolabeling, Mössbauer and EPR spectroscopy, co-immunoprecipitation, cluster transfer assays |
Nature chemical biology |
High |
17401378
|
| 2008 |
Human CFD1 (NUBP2) forms a complex with its close homologue huCfd1 (Nubp2)/huNbp35 (Nubp1) in vivo in HeLa cells. Depletion of huNbp35 (Nubp1) impairs maturation of cytosolic Fe-S proteins (including IRP1), while mitochondrial Fe-S proteins remain intact, demonstrating that the heteromeric Nubp1-Nubp2 P-loop NTPase complex is required for cytosolic Fe-S protein assembly and cellular iron homeostasis. |
RNAi knockdown, co-immunoprecipitation, Fe-S enzyme activity assays, 55Fe radiolabeling, transferrin uptake assays |
Molecular and cellular biology |
High |
18573874
|
| 2009 |
GFP fusion experiments in HeLa cells showed that N-terminal GFP tagging of NUBP2 induces nuclear localization of the fusion protein, whereas untagged or C-terminally modified forms remain cytoplasmic, suggesting that the N-terminal region of NUBP2 influences nuclear targeting. |
GFP fusion protein imaging in HeLa cells |
Molecular biology reports |
Low |
19263241
|
| 2012 |
The two central cysteine residues (CPXC motif) of the C-terminal domain of Cfd1 (NUBP2 ortholog) are essential for cell viability, Fe-S cluster coordination, and Cfd1-Nbp35 hetero-tetramer formation. The C-terminal CPXC motifs of Cfd1 and Nbp35 coordinate a bridging [4Fe-4S] cluster. Nucleotide binding is required for Fe-S cluster loading onto these scaffold proteins, as mutation of the nucleotide-binding motifs abolishes Fe-S assembly unless wild-type copies are present in trans. |
Cysteine mutagenesis, genetic complementation, Mössbauer and EPR spectroscopy, 55Fe radiolabeling, size-exclusion chromatography |
The Journal of biological chemistry |
High |
22362766
|
| 2013 |
In yeast, Nbp35 (NUBP1 ortholog) readily binds 55Fe whereas free Cfd1 (NUBP2 ortholog) does not detectably bind iron alone. Interaction of Cfd1 with Nbp35 increases the kinetic lability of assembled Fe-S clusters on Nbp35, facilitating their transfer to target apo-Fe-S proteins. A Cfd1 mutation impairing heterocomplex stability supported iron binding to Nbp35 but blocked iron release. |
55Fe radiolabeling in yeast, size-exclusion chromatography, co-immunoprecipitation, site-directed mutagenesis |
The Journal of biological chemistry |
High |
23798678
|
| 2013 |
Nubp1 and Nubp2 are integral components of centrioles throughout the cell cycle, localizing at the basal body of the primary cilium in quiescent vertebrate cells and sensory cilia in invertebrates, independently of KIFC5A. RNAi-mediated knockdown of Nubp1 or Nubp2 in quiescent NIH 3T3 cells markedly increases the number of ciliated cells, identifying Nubp1 and Nubp2 as negative regulators of ciliogenesis. Simultaneous knockdown of Nubp1 + KIFC5A restored ciliation to control levels, placing these proteins in the same pathway. |
Immunofluorescence microscopy, RNAi knockdown, cilium counting assays, genetic epistasis (double knockdown), C. elegans RNAi |
Cellular and molecular life sciences : CMLS |
High |
23807208
|
| 2015 |
The Nbp35-Cfd1 heterodimer (NUBP1-NUBP2 complex) is an ATPase. The Nbp35 homodimer and the Nbp35-Cfd1 heterodimer hydrolyze ATP, while the Cfd1 homodimer has no or very low ATPase activity. Mutation of key Walker motif residues abolishes activity. The fluorescent ATP analog mantATP binds stoichiometrically to Nbp35 with KD = 15.6 μM, and a hydrolysis-defective Nbp35 mutant shows increased KD for mantATP. |
In vitro ATPase assays, site-directed mutagenesis, fluorescence nucleotide binding (mantATP) |
The Journal of biological chemistry |
High |
26195633
|
| 2015 |
KATNAL2 isoforms directly and independently interact with both Nubp1 and Nubp2 (MRP/MinD-type P-loop NTPases) in vivo. shRNAi knockdown of Katnal2 causes enlarged cells, supernumerary centrioles, multipolar spindles, and reduced ciliogenesis, phenocopying effects of Nubp1/Nubp2 perturbation, placing KATNAL2 in the same pathway as Nubp1/Nubp2 in centriole duplication and ciliogenesis regulation. |
Co-immunoprecipitation, yeast two-hybrid, shRNAi, immunofluorescence, cell cycle analysis |
Cellular and molecular life sciences : CMLS |
Medium |
26153462
|
| 2018 |
Human CFD1 (NUBP2), in complex with NBP35 (NUBP1), performs a crucial scaffold role in the maturation of all tested cytosolic and nuclear Fe-S proteins in HeLa cells, including those involved in protein translation, DNA maintenance, and iron regulatory protein 1 (IRP1). Crystal structure of Chaetomium thermophilum holo-Cfd1 at 2.6-Å resolution revealed that two Cfd1 monomers coordinate a bridging [4Fe-4S] cluster via two conserved cysteine residues in a surface-exposed topology, and Cfd1 specifically binds ATP near the dimer interface via the Walker motif, while Nbp35 preferentially binds GTP. |
CFD1 depletion in HeLa cells, Fe-S enzyme activity assays, 55Fe radiolabeling, X-ray crystallography (2.6 Å), nucleotide binding assays |
Proceedings of the National Academy of Sciences of the United States of America |
High |
30201724
|
| 2019 |
The Cfd1 subunit of the Nbp35-Cfd1 scaffold controls nucleotide binding order: ATP must bind to Cfd1 before it can bind to Nbp35 in the heterodimer. Although the Cfd1 homodimer has no ATPase activity, Cfd1 becomes hydrolysis competent when bound to Nbp35 in the heterodimer. All forms of the CIA scaffold are specific for adenosine nucleotides and not guanosine nucleotides. |
Fluorescence nucleotide titrations, site-directed mutagenesis, ATPase assays |
Biochemistry |
Medium |
30785732
|
| 2019 |
Conditional ablation of Nubp2 in the neural crest lineage (Wnt1-Cre) in mice recapitulates the dorothy craniofacial phenotype (severe midfacial clefting) caused by a missense mutation in Nubp2. The phenotype results from markedly increased apoptosis in craniofacial mesenchyme rather than from altered ciliogenesis or SHH/FGF/BMP signaling pathway changes, demonstrating that Nubp2 is required for cranial neural crest cell survival. |
ENU forward genetic screen, exome sequencing, complementation assay with null allele, conditional Cre-lox knockout, immunofluorescence, apoptosis assays, signaling pathway marker analysis |
Developmental biology |
High |
31733190
|
| 2006 |
KIFC5A (a minus-end-directed motor protein) physically interacts with both Nubp1 and Nubp2, and Nubp1 and Nubp2 interact with each other. Knockdown of Nubp1 alone or double knockdown of Nubp1 and Nubp2 phenocopies KIFC5A silencing, causing centrosome amplification via centriole reduplication and cytokinesis defects, implicating Nubp2 in a KIFC5A-dependent pathway controlling centrosome duplication. |
Co-immunoprecipitation, RNAi knockdown, centrosome counting, cell cycle analysis, immunofluorescence |
Journal of cell science |
Medium |
16638812
|
| 2024 |
ISP I (isovalerylspiramycin I) directly targets NUBP2, and through this interaction increases the cell-membrane levels of VNN1 (vascular non-inflammatory molecule-1), which inhibits oxidative stress and fibrosis. NUBP2 knockdown or drug-mediated targeting reduced liver fibrosis markers in LX-2 cells and in BDL rat and CCl4 mouse models. |
Drug-target binding assay, VNN1 membrane fractionation, cell-based knockdown, in vivo fibrosis models |
Journal of pharmaceutical analysis |
Low |
40177065
|
| 2025 |
Conditional deletion of Nubp2 from the mouse forebrain (Emx1-Cre) causes severe primary microcephaly beginning at E18.5, associated with increased canonical and non-canonical cell death, altered neuronal proliferation and migration, and supernumerary centrosomes and cilia. Loss of p53 failed to rescue microcephaly, indicating a p53-independent mechanism. Human patients with homozygous NUBP2 variants display profound primary microcephaly, implicating NUBP2's role in centrosome and cilia regulation as critical for proper neurogenesis. |
Conditional Cre-lox knockout mouse model, patient variant identification and neurosphere complementation, immunofluorescence, cell death assays, centrosome/cilia counting, genetic epistasis (p53 rescue experiment) |
medRxivpreprint |
Medium |
39867373
|