FNDC1 Competitively Binds Gβ2 to Suppress the β-Catenin Destruction Complex and Enhance Wnt Signaling Pathway Activation

doi:10.21203/rs.3.rs-5333568/v1

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FNDC1 Competitively Binds Gβ2 to Suppress the β-Catenin Destruction Complex and Enhance Wnt Signaling Pathway Activation

https://doi.org/10.21203/rs.3.rs-5333568/v1

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Background: Elevated FNDC1 expression in gastric cancer (GC) cells activates the Wnt/β-catenin pathway, contributing to their malignant traits. However, the exact mechanism governing this process remains unclear.

Methods: Bioinformatics analyses were used to identify the expression of FDNC1 in pan-cancer, its correlation with clinical outcomes, and biological functions in GC. Co-immunoprecipitation assays and western blot elucidate the interaction between FDNC1 and Gβ2/Gγ2 and the expression of Axin1, GSK3β, APC, and Dvl. The specific binding sites of FNDC1 and Gβ2 were explored by co-immunoprecipitation.

Results: FNDC1 was highly expressed in GC tissue, and its expression level is positively correlated with poor prognosis of GC. Functional enrichment analysis shows that FNDC1-related genes may participate in regulating the Wnt signaling pathway. In vitro assays prove that FNDC1 competitively binds to the Gβ2 protein. This binding caused Dvl to separate from Gβγ. Subsequently, Dvl was released and recruited Axin1, facilitating the degradation of Axin1 and activating the Wnt/β-catenin signaling pathway. We further identified the WD5 amino acid segment (residues 224-254) as the specific binding region of FNDC1 on Gβ2.

Discussion: This study reveals a novel mechanism where FNDC1 competitively binds Gβ2, inhibiting β-catenin degradation and enhancing the Wnt/β-catenin signaling pathway.

Wnt/β-catenin signaling pathway

Gastric cancer (GC)

Fibronectin Type III Domain Containing 1(FNDC1)

Gβγ subunit

Dishevelled (Dvl)

Gastric cancer (GC) is a prevalent malignant tumor affecting the digestive tract, with a high incidence and mortality rate (1). While surgery coupled with perioperative treatment may enhance disease-free survival (DFS), close to 50% of GC patients encounter recurrence and metastasis within two years of radical resection (2). Hence, it is crucial to identify specific molecular markers linked to GC recurrence and metastasis.

The Fibronectin Type III Domain Containing 1(FNDC1) gene on human chromosome 6q25.3 is a receptor-independent activator of Guanine nucleotide-binding protein (G protein) signal transduction. It activates G protein signaling by binding to the Guanine nucleotide-binding protein beta/gamma (Gβγ) subunit (3). In the previous study, we discovered a link between peritoneal metastasis (PM) and FNDC1 by conducting whole exome sequencing (WES) of GC pathological tissue (4) and subsequently confirmed that FNDC1 promotes epithelial-mesenchymal transition (EMT) in GC cells by activating the Wnt/β-catenin signaling pathway (5). However, the mechanism by which FNDC1 activates the Wnt/β-catenin signaling pathway remains unclear.

The FNDC1 protein is mainly found in the nucleus and extracellular matrix of cells. In cardiac tissue, it has been discovered that the FNDC1 protein can activate the G protein signaling pathway by binding to the Gβγ subunit of the G protein (6). Gβγ, an essential factor in signal transduction, plays a vital role in the development of various malignant tumors such as breast and ovarian cancer (7, 8). Research has revealed that the Gβγ subunit plays a pivotal role in the regulation of the Wnt/β-catenin signaling pathway, influencing both its sustained activation and termination (9). When a Wnt ligand binds to the Frizzled (FDZ) and Low-density lipoprotein receptor-related protein 5/6 (LRP5/6) complex on the cell membrane, it recruits two intracellular proteins: Dishevelled (Dvl) and Axis Inhibition Protein (Axin). After this recruitment, Axin forms a complex with LRP5/6 and Gβγ. Then, Axin is tagged with ubiquitin, leading to its degradation. In the absence of Wnt ligands, the GSK3β-APC-Axin complex phosphorylates soluble β-catenin. This process results in the ubiquitination and degradation of β-catenin (10). Subsequently, Gβγ binds to Dvl, inducing Dvl's ubiquitination while inhibiting the degradation of Axin. This series of molecular events ultimately leads to the inhibition and deactivation of the Wnt/β-catenin signaling pathway (11, 12).

We explored its regulatory mechanisms and functional roles to understand better how FNDC1 activates the Wnt/β-catenin signaling cascade. Our study has discovered a new interaction between FNDC1 and the Gβ2 subunit. This interaction prevents the Gβγ-dependent inactivation of the Wnt/β-catenin pathway by obstructing the binding of Gβγ to Dvl, thereby maintaining the signaling pathway in an active state. These findings provide a deeper insight into the molecular basis of FNDC1's role in regulating the Wnt/β-catenin signaling and its potential implications in cellular processes and the development of diseases.

Bioinformatics analysis of FNDC1

The mRNA expression of FNDC1 in normal and tumor tissues was compared using TCGA samples, while protein levels were investigated via the HPA database. Kaplan-Meier analysis assessed the association between FNDC1 expression and clinical outcomes in GC, with survival curves showing p-values under 0.05. ROC curves were created for tumors influenced by FNDC1, and GEPIA2 identified the 100 most relevant genes for gene ontology (GO) analysis [include biological pathways (BP), cellular components (CC), and molecular functions (MF)] and KEGG analysis to explore FNDC1's functions. GSEA analysis followed based on differential FNDC1 expression in GC.

Cell Culture

The gastric cell line HGC-27 was obtained from the American Tissue Culture Collection (ATCC, Rockville, MD, USA). HGC-27 and HEK293T cell lines were cultured in Dulbecco’s modified Eagle’s medium (Gibco, NE, USA) supplemented with 10% fetal bovine serum (Gibco, NE, USA) and 100 U/L penicillin-streptomycin solution. The cultures were maintained at 37°C in a humidified atmosphere with 5% CO₂.

Plasmids and stable or transient transfections

The lentivirus vector shRNA-FNDC1 was constructed as previously described (5). The shRNA-Gβ2 sequence is 5-CCGGCGGCCATGAATCCGACATCAACTCGAGTTGATGTCGGATTCATGGCCGTTTTT-3, and the shRNA-Gγ2 sequence is 5-CCGGGCTTAAGATGGAAGCCAATATCTCGAGATATTGGCTTCCATCTTAAGCTTTTTTG-3". As previously described, these shRNAs were transfected into HGC-27 cells to establish HGC-27-shRNA-Gγ2-cells, HGC-27-shRNA-Gβ2 group cells, and HGC-27-shRNA-NC group cells. The transfection efficiency was subsequently verified by Western blot analysis.

The entire length of FNDC1-FLAG was chemically synthesized and cloned into vector pCMV-C-FLag using the Not I and Xba I sites. Then, the recombinant plasmid was transfected to HGC-27 cells as described (5). Specific primers for the CDS region of Gβ2 were designed, incorporating the enzyme cutting sites Nhe I and EcoR I at both ends by the multiple cloning site of the pcDNA3.1-HA vector. The CDS region of Gβ2 was amplified, and the PCR product containing the Nhe I and EcoR I cutting sites was purified. Gβ2 is divided into seven segments(WD1-WD7, Fig. 5. A). Synthetically obtained WD1 + WD2, WD2 + WD3, WD3 + WD4, WD4 + WD5, WD5 + WD6, WD6 + WD7, WD1 + WD7 with two enzyme cutting sites of Nhe I and EcoR I, △-WD5 sequence is directly inserted into the pcDNA3.1-HA vector through double enzyme digestion. Plasmids were transfected into HGC-27 cells when they reached 30 to 50% confluence, using Lipofectamine™ 3000 Transfection Reagent (Thermo Fisher Scientific, MA, US).

Cell co-culture model

We constructed a cell co-culture model using 0.4 µm transwell chambers. Briefly, HGC-27-shRNA-Gβ2 cells、HGC-27-shRNA-Gγ2 cells, and the control groups (5×10⁵ cells) were seeded into the lower layer of the culture system (6-well plate), and the Flag-FNDC1-HGC-27 cells (1×10⁵ cells) were seeded into the upper layer of the culture system. After 24 hours of culturing, the transwell chambers were removed. The cells in the lower layer were used for immunoprecipitation analysis.

Real-time qPCR

As previously described, total RNA was prepared for SYBR Green-based qPCR analysis (5). The mRNA levels of the target gene in each well were normalized to the mRNA levels of GAPDH using the 2 − ΔΔCq method. Primers Used in Real-Time qPCR are shown in Supplementary1.

Western blot analysis.

Proteins extracted from cell lines were subjected to WB analysis. The primary Abs used were Anti-GSK3β (ab2602), Anti-APC (ab40778), Anti-GAPDH (ab181602), Anti-LRP5(ab36121), Anti-LRP6 (ab75358), Anti-Ubiquitin (ab7780), Anti-Frizzled-1 (ab126262), Anti-Frizzled-2 (ab109094), Anti-Dvl1 (ab233003), Anti-Dvl2 (ab22616), Anti-Dvl3 (ab76081), Anti-GNB2 (ab81272), Anti-GNG2 (ab198225) were purchased from Abcam(Cambridge, UK); Anti-FNDC1 (HPA030963) was purchased from Sigma ( St. Louis, MO, USA); Anti- β-catenin(8480), Anti-Axin1 (2074), Anti-Flag (14793) was purchased from Cell Signaling Technology (Boston, USA); Anti-Dvl1 (sc-8025) was purchased from Santa Cruz Biotechnology (Inc. Delaware Ave, USA). HRP-conjugated secondary Ab (EarthOx) at room temperature for 1.5 hours.

Co-immunoprecipitation analysis

For co-immunoprecipitation analysis, cells were lysed using a cold lysis buffer, and the resulting supernatant was collected after centrifugation at 13,000 g for 10 minutes. Approximately 1000 µg of protein was incubated with a specific immunoprecipitation (IP) antibody (1:50) at 4°C on a rotating platform overnight. For the second immunoprecipitation, the Anti-Gβ2 antibody was mixed with the precipitate and incubated again. Pierce Protein A/G Magnetic Beads (25 µL) were added to the antigen-antibody mixture and incubated at room temperature for 1 hour. After washing, the target antigen-antibody complex was eluted with 100 µL of Elution Buffer and 10 µL of Neutralization Buffer. This was followed by Western blotting analysis.

1. FNDC1 facilitates the process of ubiquitination and subsequent degradation of Axin1.

FNDC1 is overexpressed in multiple cancer types (Supplementary Fig. 1) and promotes GC development and progression (Supplementary Fig. 2); GSEA shows that FNDC1-related genes may regulate the Wnt signaling pathway. In vitro assays (Supplementary Fig. 3). FNDC1 knockdown GC cells were achieved by infecting HGC-27 GC cells with lentivirus carrying short hairpin RNA (shRNA) targeting FNDC1(Fig. 1.A). As shown in Fig. 1.B-F, knocking down of FNDC1 significantly increases the protein expression level of Axin1, a critical scaffold protein in the Wnt/β-catenin signaling pathway; in contrast, there is no significant change in GSK3β, phos-GSK3β, and APC protein levels. Further investigation using qPCR revealed that FNDC1 does not significantly affect the mRNA transcription of Axin1 (Fig. 1. G). Blocking protein degradation with proteasome inhibitor showed that FNDC1 knockdown promotes the ubiquitination of Axin1, leading to its degradation (Fig. 1. H). Additionally, the co-immunoprecipitation assay demonstrated a significant increase in the association of Axin1 with GSK3β and GSK3β with APC in the absence of FNDC1 (Fig. 1. I). These findings suggest that FNDC1 modulates the stability of the GSK3β-APC-Axin1 complex and reduces Axin1 protein levels, which could ultimately lead to β-catenin accumulation.

2. FNDC1 blocks the degradation of Dvl

Next, we investigated the expression of the proteins that interact with Axin to form this complex. Western Blot shows that the downregulation of FNDC1 may reduce the protein levels of Dvl1, Dvl2, and Dvl3; however, the expression of LRP5/6 and Frizzled 1/2 remained unchanged (Fig. 2.A-H). The mRNA levels of Dvl1, Dvl2, and Dvl3 were unaffected (Fig. 2.I-K). To clarify how FNDC1 mediates Dvl overexpression, we intervened in the proteolytic pathway using the proteasome inhibitor MG132. The results demonstrated that MG132 effectively prevented the degradation of Dvl induced by FNDC1 knockdown (Fig. 2.L-O). This suggests that FNDC1 functions to suppress Dvl protein degradation.

3. FNDC1 enhanced Dvl accumulation at the cell membrane

We found no significant changes in the cytoplasmic protein levels of Dvl1, Dvl2, and Dvl3 in FNDC1-downregulated HGC-27 cells. However, we observed a notable reduction in their membrane expression levels, with Dvl1 showing the most significant decrease (Fig. 3.A-G). Our findings indicate that FNDC1 increases Dvl accumulation at the cell membrane. This accumulation facilitates the ubiquitin-dependent degradation of Axin, which may be a key mechanism for activating the Wnt/β-catenin signaling pathway. To explore the mechanism underlying FNDC1-induced Dvl accumulation at the membrane, we chose Dvl1 for further investigation because the classic Wnt/β-catenin signaling pathway responds most significantly to changes in the abundance of Dvl3 or Dvl1 (13).

4. Competitive binding of FNDC1 to Gβ2 leads to degradation of Dvl1

We investigated how FNDC1 inhibits Dvl degradation. Previous studies show that the Gβ and Gγ subunits of heterotrimeric G proteins interact with Dvl. This interaction leads to the ubiquitination and degradation of Dvl. As shown in Fig. 4A, FNDC1 knockdown enhanced the interaction between Dvl1 and Gβ2/Gγ2. Next, we created HGC-27-shRNA-Gβ2 and HGC-27-shRNA-Gγ2 cells (Fig. 4B-D). Using co-immunoprecipitation (Co-IP) assays, we confirmed the interaction between FNDC1 and Gβ2/Gγ2, but not with Dvl1 (Fig. 4E). Knockdown of Gβ2 abolished the interaction between FNDC1 and both Gβ2 and Gγ2. In contrast, the knockdown of Gγ2 did not affect the interaction between FNDC1 and Gβ2, indicating that FNDC1 primarily interacts directly with Gβ2 (Fig. 4F). Further investigation with secondary Co-IP assays in HGC-27 cells overexpressing FNDC1 revealed that, upon binding to FNDC1, Gβ2 showed no significant interaction with Dvl1 (Fig. 4G). These findings suggest that FNDC1 competes with Dvl1 for binding to Gβ2, which decreases Dvl1's binding to Gβ2 and consequently increases Dvl1 levels.

5. Investigating the precise binding location of FNDC1 on the G protein.

To better identify the binding site of FNDC1 on the G protein, we created several Gβ2 amino acid sequence fragments, labeled WD1 to WD7 (Fig. 5. A), each tagged with an HA epitope, along with a full-length Gβ2 sequence. The results showed that co-transfecting plasmids encoding HA-WD5 + WD6 and Flag-FNDC1, along with HA-WD4 + WD5 and Flag-FNDC1, into 293T cells led to detectable complex formation between the Flag and HA tags, confirming the interaction between FNDC1 and the WD5 domain of Gβ2 (Fig. 5. B). Subsequently, we constructed a Gβ2 plasmid lacking the WD5 sequence (HA-Δ-WD5) (Fig. 5. C) and co-transfected it with the Flag-FNDC1 plasmid into 293T cells. Compared to the full-length Gβ2, the deletion of WD5 resulted in the absence of detectable Flag and HA tag complexes in the immunoprecipitation assay (Fig. 5. D), suggesting that the WD5 sequence is critical for the interaction between Gβ2 and FNDC1. Collectively, these findings establish that the WD5 amino acid segment (residues 224 a.a. − 254 a.a.) is the binding region of FNDC1 on Gβ2. In the recovery experiment, we observed that following the deletion of the WD5 fragment in Gβ2, there was a significant reduction in the expression level of Axin1 within HGC-27 cells (Fig. 5. E-F), along with a marked upregulation of Dvl1 at the cell membrane (Fig. 5. J). Conversely, the protein levels of APC and pGSK-3β showed no significant changes (Fig. 5. E, G-I), indicating a selective impact on Axin1 expression. Concurrently, immunoprecipitation assays also confirmed that the interaction between GSK-3β and both Axin1 and APC was attenuated after the deletion of the WD5 fragment (Fig. 5. K), suggesting that the loss of the WD5 segment in Gβ2 inhibits the formation of the β-Catenin destruction complex. Similarly, the absence of WD5 led to increased ubiquitination of Axin1.

Despite the prevalence of gastric cancer, there is a current shortage of reliable biomarkers that can help predict prognosis and guide treatment decisions (15). Thus, it is crucial to find biomarkers that help with early detection and identify new treatment targets for GC.

FNDC1 is an emerging biomarker associated with the development of various malignant tumors. Elevated levels of FNDC1 expression have been correlated with a poorer prognosis in gastric cancer patients (16, 17). This protein has a unique localization pattern, expressed in the nucleus and secreted into the extracellular matrix. FNDC1's dual localization gives it characteristics of both an intracellular protein and a secretory factor. This dual role implies that FNDC1 may be crucial in cellular functions and tumorigenesis. Therefore, FNDC1 has significant potential as a biomarker for cancer detection and could open new avenues for therapeutic intervention.

Reddy et al.(18) found that high levels of FNDC1 expression in head and neck squamous cell carcinoma significantly affect patient prognosis. At the same time, Chen et al. (19) discovered that FNDC1 is overexpressed in breast cancer and acts as an oncogene. Their study showed that suppressing FNDC1 inhibits the PI3K/Akt signaling pathway, which is essential for cancer cells' survival and proliferation. Moreover, other studies have identified FNDC1 as a potential prognostic indicator in breast cancer, highlighting its significance as a biomarker for clinical outcomes (20). Recent research (3) has linked FNDC1 to VEGF-regulated cellular activities such as angiogenesis, migration, and proliferation.

Additionally, microRNA-1207-3p induces apoptosis in prostate cancer cells by targeting FNDC1 (21). Recent studies indicate that FNDC1 is upregulated in GC, which promotes EMT and is linked to poor patient prognosis (16, 17, 22). These findings highlight FNDC1's complex role in cancer development and its potential as a prognostic biomarker in GC. Nevertheless, the molecular mechanisms by which FNDC1 facilitates EMT in GC cells remain largely unexplored. Our previous research demonstrated that FNDC1 promotes EMT by activating the Wnt/β-catenin signaling pathway in laboratory and animal models. Further delineation of these mechanisms is crucial for a thorough understanding of FNDC1's role in GC progression and for developing targeted therapeutic strategies.

This study aims to clarify how FNDC1 activates the Wnt/β-catenin signaling pathway. In this pathway, the stability of cytosolic β-catenin acts as a crucial regulatory switch. This stability is controlled by the Axin-GSK3β-APC complex, which is essential for regulating β-catenin levels and the activation of Wnt signaling. The expression levels of the Axin protein are recognized as a critical factor that depends on concentration within the β-catenin destruction complex (23). This indicates that both the expression levels and the functional integrity of Axin adjust the cellular response to Wnt signaling. The Axin family consists of two paralogs, Axin1 and Conductin/Axin2. Recent studies show Axin2 has a weaker suppressive effect on canonical Wnt signaling than Axin1(24).

Our investigation reveals that FNDC1 promotes the ubiquitination and degradation of Axin1 and disrupts its interaction with GSK3β and APC. The Wnt signaling cascade is activated when Wnt ligands bind to Frizzled and LRP5/6 receptors on the cell membrane, which triggers Dvl protein activation. This activation recruits Axin to the plasma membrane, which is targeted for ubiquitination and degradation, thus relieving its inhibition of β-catenin activation (12). The above process underscores the dependency of Axin ubiquitination on Dvl protein activation. We found that FNDC1 does not alter the expression levels of Frizzled1/2 and LRP5/6, but it significantly increases the protein levels of Dvl1/2/3. The proteasome inhibitor MG132 confirmed that FNDC1 affects Dvl1/2/3 at the post-transcriptional level, meaning it influences protein levels rather than gene expression.

Dishevelled (Dvl) is a pivotal intracellular signaling molecule that positively modulates the Wnt signaling pathway (25). The activation of Dvl is controlled by the Gβγ subunit of the heterotrimeric G protein in this pathway. The heterotrimeric G protein is a complex comprised of three distinct subunits: α, β, and γ. This complex is integral to cellular signaling. Precisely, the Gβγ subunits form a non-covalent dimer. This dimer is often considered functionally monomeric due to its strong association and resistance to dissociation under non-denaturing conditions (7). The βγ subunit complex primarily localizes to the inner side of the plasma membrane, where it interacts with downstream effector molecules, transducing signals from the cell surface to the intracellular environment. Extant research has identified the Gβγ subunit, a critical mediator in signal transduction, as playing a significant role in the pathogenesis of various malignant tumors, including breast and ovarian cancers (8). Notably, the study by Nathalie et al. (26) has highlighted the interplay between Gβγ and Dvl as crucial in modulating the suppression of the Wnt/β-catenin signaling pathway. During Wnt signaling activation, the binding of Gβγ to Dvl is instrumental in preventing the phosphorylation of β-catenin by the Axin complex, thereby facilitating β-catenin stabilization and averting its degradation. Previous research found that high levels of FNDC1 in AGS and SGC7901 cell lines form a complex with Gβγ and VEGFR2. This complex promotes VEGFR phosphorylation and activates the RAS-MAPK or PI3K-AKT signaling pathways (27).

We performed a series of co-IP experiments to validate the proposed molecular mechanism depicted. Our results show that FNDC1 regulates Dvl1 expression by interacting with Dvl1 and Gβ2. FNDC1 can competitively bind to Dvl1, preventing Dvl1 from binding to Gβ2 on the inside of the cell membrane. This reduces the affinity of the Gβγ subunit for Dvl1. As a result of this competitive binding, the Gβγ subunit dissociates from Dvl1. This leads to increased levels of Dvl1 inside the cell and promotes the degradation of Axin1. To determine the interaction between FNDC1 and Gβ2, we created a series of Gβ2 protein deletion mutants to identify the exact binding site. Following a systematic analysis, we localized the primary interaction domain to the amino acid sequence spanning positions 224 to 254. Our mutagenesis study confirmed that this specific region, crucial for mitochondrial fusion and cellular signaling, is the critical binding domain. Prior literature supports the biological relevance of this fragment in cellular processes (28, 29).

In conclusion, our study shows that FNDC1 positively influences the Wnt/β-catenin signaling pathway. This research improves our understanding of FNDC1's role in the β-catenin destruction complex. We have demonstrated that FNDC1 disrupts the interaction between Gβγ and Dvl by competing with Gβ2 in GC cells. This disruption stabilizes Dvl, which promotes the continuous activation of the Wnt/β-catenin pathway. As a result, it enhances GC cells' invasive and metastatic potential. Our findings indicate that FNDC1 is a new oncogenic factor in GC, suggesting it could be a potential therapeutic target.

Disclosures. Tao Jiang, Hao Chen, Fangyu Lin,Jialin Liu,Xiaoyan Lin, and Wenyu Gao have nothing to disclose.

Data Availability. All data generated or analyzed during this study are included in this published article or supplementary information files.

Human Ethics and Consent to Participate declarations: Not applicable。

Declaration of Helsinki: Not applicable.

Funding.

This study was supported by the National Natural Science Foundation of China (NSFC), Young Scientists Fund (Grant Number: 82203777), Fujian Provincial Natural Science Foundation of China (Grant Number: 2021J01736), and Joint Funds for the Innovation of Science and Technology, Fujian province (Grant Number: 2021Y9045). Fujian Provincial Natural Science Foundation of China (Grant Number: 2022J05053)

Author Contribution

Tao Jiang and Hao Chen contributed equally to this work and were involved in the conception and design of the study, as well as the acquisition, analysis, and interpretation of data. They also drafted the manuscript and figures. Fangyu Lin and Jialin Liu were involved in the experimental work, data collection, and provided critical revisions to the manuscript. Xiaoyan Lin participated in the design of the study and performed the statistical analysis. Wenyu Gao, the corresponding author, was involved in the conception and design of the study, oversaw the experiments, and provided final approval of the version to be published. All authors read and approved the final manuscript.

ACKNOWLEDGEMENTS

We want to thank all the participants who made this study possible.

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No competing interests reported.

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FNDC1 Competitively Binds Gβ2 to Suppress the β-Catenin Destruction Complex and Enhance Wnt Signaling Pathway Activation

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Abstract

Figures

BACKGROUND

MATERIALS AND METHODS

Bioinformatics analysis of FNDC1

Cell Culture

Plasmids and stable or transient transfections

Cell co-culture model

Real-time qPCR

Co-immunoprecipitation analysis

RESULTS

2. FNDC1 blocks the degradation of Dvl

3. FNDC1 enhanced Dvl accumulation at the cell membrane

4. Competitive binding of FNDC1 to Gβ2 leads to degradation of Dvl1

DISCUSSION

Declarations

Funding.

Author Contribution

ACKNOWLEDGEMENTS

References

Additional Declarations

Supplementary Files

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