| Claim category | Specific finding | Experimental system/assay | Quantitative/statistical detail (if present) | Citation context ID(s) | Publication (author, year, DOI/URL) |
|---|---|---|---|---|---|
| Identity/domains | FBXL13 is the human gene/protein corresponding to UniProt Q8NEE6; it is an F-box protein with leucine-rich repeats and has also been annotated as DRC6. | Gene/protein annotation and literature synthesis in primary paper and reviews. | Human F-box family context: approximately 69 human F-box proteins; FBXL13 belongs to the FBXL subgroup. | (pqac-00000002, pqac-00000003) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Complex/biochemistry | FBXL13 forms a functional SCF ubiquitin ligase complex; SKP1 binding depends on the F-box domain, and FBXL13 was detected with SCF components including SKP1/CUL1. | Co-immunoprecipitation; WT versus ΔF-box mutant analysis; affinity purification/proteomics. | Functional loss with ΔF-box mutant indicates requirement for SCF assembly. | (pqac-00000001, pqac-00000005, pqac-00000006) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Interacting partners | FBXL13 interacts with Centrin-2, Centrin-3, CEP152, and CEP192; Centrin binding maps to the amino-terminal region, whereas CEP192 binding requires the carboxy-terminus. | LC-MS interactome analysis; co-immunoprecipitation; interaction mapping with truncation constructs; in vitro reconstitution. | Proteomics identified 25 unique interactors for FBXL13 isoform 1 and 21 for isoform 3; control compendium comprised 30 datasets and 2,850 agarose-binding proteins. | (pqac-00000001, pqac-00000004, pqac-00000006, pqac-00000007) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Substrates | CEP192 isoform 3 is the key experimentally supported ubiquitylation substrate of SCF^FBXL13; Centrin-2/3 bind FBXL13 but are not detectably degraded by it. | In vivo ubiquitylation assays; co-expression with HA-ubiquitin; knockdown/rescue; immunoblotting. | CEP192 polyubiquitylation is reduced/abolished by FBXL13 depletion and promoted by FBXL13 WT but not ΔF-box. | (pqac-00000001, pqac-00000004, pqac-00000005) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Substrate-binding region | FBXL13 directly binds the amino-terminal region of CEP192; the mapped CEP192 interaction region is reported as aa 1–602/630 depending on construct usage. | CEP192 fragment mapping with Myc-tagged constructs; endogenous and ectopic co-IP; in vitro reconstitution. | CEP192 fragments used included aa 1–630 and aa 631–2537; direct interaction supported for aa 1–602/630 region. | (pqac-00000003, pqac-00000006, pqac-00000007) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Localization | FBXL13 is diffusely cytoplasmic but enriched at centrosomes. | Immunofluorescence microscopy in U2OS cells using centrosomal markers (including γ-tubulin/centrin-3). | Qualitative centrosomal enrichment reported; fluorescence quantified with ImageJ ROIs in later assays. | (pqac-00000002, pqac-00000006, pqac-00000007, pqac-00000008) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Biological function | FBXL13 fine-tunes CEP192 abundance to maintain centrosome homeostasis and steady-state centrosomal microtubule nucleation activity. | Overexpression and knockdown studies; centrosome immunofluorescence; microtubule regrowth assays. | Overexpression lowers centrosomal CEP192/γ-tubulin and suppresses microtubule regrowth; depletion increases centrosomal CEP192 and γ-tubulin. | (pqac-00000001, pqac-00000002, pqac-00000003, pqac-00000005) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Protein stability / proteolysis | FBXL13 overexpression accelerates CEP192 proteolysis, while proteasome inhibition (MG132) rescues CEP192 reduction and FBXL13 knockdown stabilizes/increases CEP192. | Cycloheximide chase; MG132 rescue; immunoblotting with ImageJ quantification. | CHX chase (CEP192/β-actin values normalized to 0 h vector control) reported as: 1.00, 0.54, 0.44, 0.30, 0.19, 0.05, 0.08, 0.08 across vector/FBXL13 time-course lanes shown in Fig. 4D. | (pqac-00000003, pqac-00000004, pqac-00000009) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Centrosome phenotype | FBXL13 depletion causes increased centrosomal CEP192 and a significant increase in centrosomal γ-tubulin intensity; overexpression causes the opposite effect. | Centrosomal fluorescence quantification by immunofluorescence microscopy. | Numeric values are not present in extracted text; figure locations for quantification are Fig. 6D (overexpression) and Fig. 6G (knockdown). | (pqac-00000002, pqac-00000003, pqac-00000005, pqac-00000009) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Microtubule nucleation phenotype | FBXL13 overexpression reduces the ability of cells to regrow centrosomal microtubules after complete depolymerization. | Nocodazole depolymerization followed by 1 min microtubule regrowth assay. | Assay conditions reported: nocodazole 10 µM for 2 h at 4°C, then 1 min recovery; exact regrowth percentages require figure extraction. | (pqac-00000001, pqac-00000003, pqac-00000008, pqac-00000009) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Cell migration phenotype | FBXL13 depletion markedly reduces cell motility in a 2-D scratch assay; the defect is rescued by siRNA-resistant FBXL13 WT but not ΔF-box, and also rescued by co-depletion of CEP192-3. | Scratch-wound migration assay with knockdown/rescue. | Exact wound-closure values are not in extracted text; relevant quantification panels are Fig. 7B and Fig. 7E. | (pqac-00000002, pqac-00000005, pqac-00000009) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Additional phenotype | FBXL13 depletion causes a minor yet significant centrosome overduplication phenotype. | RNAi depletion followed by centrosome phenotyping. | Reported qualitatively as minor but significant; exact percentage requires figure extraction. | (pqac-00000005) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Methods / datasets / URLs | Proteomics and microscopy datasets support the FBXL13 interactome and centrosome biology conclusions. | LC-MS interactome, confocal IF, ubiquitylation assays, CHX chase, qPCR, microtubule regrowth. | PRIDE proteomics dataset accession PXD008310; MLN4924 used at 2 µM in interactome prep; MG132 10 µM for 5 h; CHX 100 µg/ml; qPCR reported as mean ± SD from three triplicates. | (pqac-00000006, pqac-00000008) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |
| Review context / interpretation | Available review context treats FBXL13 as a relatively understudied FBXL-family member; the strongest direct functional evidence remains the centrosome/CEP192 study rather than a firmly established role in ciliary N-DRC biology in human cells. | Narrative review context cross-referenced against primary data. | No direct quantitative data beyond the primary paper. | (pqac-00000002, pqac-00000006) | Fung et al., 2018, EMBO Reports, https://doi.org/10.15252/embr.201744799 |


*Table: This table summarizes the main experimentally supported facts about human FBXL13/Q8NEE6 from the key primary study by Fung et al. It highlights validated interactions, substrate evidence, localization, phenotypes, and the limited but important quantitative details available from the extracted evidence.*