Enhanced canonical Wnt signaling during early zebrafish development perturbs the interaction of cardiac mesoderm and pharyngeal endoderm and causes thyroid specification defects

AbstractBackgroundCongenital hypothyroidism (CH) due to thyroid dysgenesis is a frequent congenital endocrine disorder for which the molecular mechanisms remain unresolved in the far majority of cases. This situation reflects in part our still limited knowledge about the mechanisms involved in the early steps of thyroid specification from the endoderm, in particular the extrinsic signaling cues that regulate foregut endoderm patterning. In this study, we used small molecules and genetic zebrafish models to characterize the role of various signaling pathways in thyroid specification.MethodsWe treated zebrafish embryos during different developmental periods with small molecule compounds known to modulate the activity of Wnt signaling pathway and observed effects in thyroid, endoderm and cardiovascular development using whole mount in situ hybridization and transgenic fluorescent reporter models. We used an antisense morpholino to create a zebrafish acardiac model. For thyroid rescue experiments, BMP pathway induction in zebrafish embryos was obtained by using heatshock inducible transgenic lines.ResultsInterestingly, combined analyses of thyroid and cardiovascular development revealed that overactivation of Wnt signaling during early development leads to impaired thyroid specification concurrent with severe defects in the cardiac specification. When using a model of morpholino-induced blockage of cardiomyocyte differentiation, a similar correlation was observed, suggesting that defective signaling between cardiac mesoderm and endodermal thyroid precursors contributes to thyroid specification impairment. Rescue experiments through transient overactivation of BMP signaling could partially restore thyroid specification in models with defective cardiac development.ConclusionCollectively, our results indicate that BMP signaling is critically required for thyroid cell specification and identify cardiac mesoderm as a likely source of BMP signals.

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Small Molecule Screening in Zebrafish Embryos Identifies Signaling Pathways Regulating Early Thyroid Development

10.1101/551861 ◽

2019 ◽

Cited By ~ 1

Author(s):

Benoit Haerlingen ◽

Robert Opitz ◽

Isabelle Vandernoot ◽

Achim Trubiroha ◽

Pierre Gillotay ◽

...

Keyword(s):

Signaling Pathways ◽

Small Molecule ◽

Molecular Mechanisms ◽

Model Organisms ◽

Thyroid Cell ◽

Zebrafish Embryos ◽

Cardiovascular Development ◽

Drug Induced ◽

Thyroid Development

AbstractBackgroundDefects in embryonic development of the thyroid gland are a major cause for congenital hypothyroidism in human newborns but the underlying molecular mechanisms are still poorly understood. Organ development relies on a tightly regulated interplay between extrinsic signaling cues and cell intrinsic factors. At present, however, there is limited knowledge about the specific extrinsic signaling cues that regulate foregut endoderm patterning, thyroid cell specification and subsequent morphogenetic processes in thyroid development.MethodsTo begin to address this problem in a systematic way, we used zebrafish embryos to perform a series of in vivo phenotype-driven chemical genetic screens to identify signaling cues regulating early thyroid development. For this purpose, we treated zebrafish embryos during different developmental periods with a panel of small molecule compounds known to manipulate the activity of major signaling pathways and scored phenotypic deviations in thyroid, endoderm and cardiovascular development using whole mount in situ hybridization and transgenic fluorescent reporter models.ResultsSystematic assessment of drugged embryos recovered a range of thyroid phenotypes including expansion, reduction or lack of the early thyroid anlage, defective thyroid budding as well as hypoplastic, enlarged or overtly disorganized presentation of the thyroid primordium after budding. Our pharmacological screening identified BMP and FGF signaling as key factors for thyroid specification and early thyroid organogenesis, highlight the importance of low Wnt activities during early development for thyroid specification and implicate drug-induced cardiac and vascular anomalies as likely indirect mechanisms causing various forms of thyroid dysgenesis.ConclusionsBy integrating the outcome of our screening efforts with previously available information from other model organisms including Xenopus, chicken and mouse, we conclude that signaling cues regulating thyroid development appear broadly conserved across vertebrates. We therefore expect that observations made in zebrafish can inform mammalian models of thyroid organogenesis to further our understanding of the molecular mechanisms of congenital thyroid diseases.

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Equine Genital Squamous Cell Carcinoma Associated with EcPV2 Infection: RANKL Pathway Correlated to Inflammation and Wnt Signaling Activation

Biology ◽

10.3390/biology10030244 ◽

2021 ◽

Vol 10 (3) ◽

pp. 244

Author(s):

Samanta Mecocci ◽

Ilaria Porcellato ◽

Federico Armando ◽

Luca Mechelli ◽

Chiara Brachelente ◽

...

Keyword(s):

Gene Expression ◽

Wnt Signaling ◽

Squamous Cell ◽

Molecular Mechanisms ◽

Animal Health ◽

Wnt Signaling Pathway ◽

Nuclear Factor ◽

Nuclear Factor Kappa ◽

Signaling Activation ◽

Expression Evaluation

Equine genital squamous cell carcinomas (egSCCs) are among the most common equine tumors after sarcoids, severely impairing animal health and welfare. Equus caballus papillomavirus type 2 (EcPV2) infection is often related to these tumors. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with EcPV2 infection, investigating receptor activator of nuclear factor-kappa B ligand (RANKL) signaling in NF-kB pathway, together with the Wnt and IL17 signaling pathways. We analyzed the innate immune response through gene expression evaluation of key cytokines and transcription factors. Moreover, Ki67 index was assessed with immunohistochemistry. EcPV2-E6 DNA was checked, and viral presence was confirmed in 21 positive out to 23 cases (91%). Oncogene expression was confirmed in 14 cases (60.8%) for E6 and in 8 (34.7%) for E2. RANKL, nuclear factor kappa-light-chain-enhancer of activated B cells (NFKB)-p50, NFKBp65, interleukin (IL)-6, IL17, IL23p19, IL8, IL12p35, IL12p40, β-catenin (BCATN1), FOS like 1 (FOSL1), and lymphoid enhancer binding factor 1 (LEF1) showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the activation of RANKL/RANK and IL17 with the relative downstream pathways, and a positive modulation of inflammatory cytokines genes such as IL6 and IL8. Moreover, the increase of BCATN1, FOSL1, and LEF1 gene expression suggests an activation of both canonical and non-canonical Wnt signaling pathway that could be critical for carcinogenesis and tumor progression.

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DNA methylation mediated RSPO2 to promote follicular development in mammals

Cell Death and Disease ◽

10.1038/s41419-021-03941-z ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Xiaofeng Zhou ◽

Yingting He ◽

Nian Li ◽

Guofeng Bai ◽

Xiangchun Pan ◽

...

Keyword(s):

Dna Methylation ◽

Wnt Signaling ◽

Signaling Pathway ◽

Methylation Level ◽

Molecular Mechanisms ◽

Cpg Island ◽

Wnt Signaling Pathway ◽

Follicular Development ◽

Expression Level

AbstractIn female mammals, the proliferation, apoptosis, and estradiol-17β (E2) secretion of granulosa cells (GCs) have come to decide the fate of follicles. DNA methylation and RSPO2 gene of Wnt signaling pathway have been reported to involve in the survival of GCs and follicular development. However, the molecular mechanisms for how DNA methylation regulates the expression of RSPO2 and participates in the follicular development are not clear. In this study, we found that the mRNA and protein levels of RSPO2 significantly increased during follicular development, but the DNA methylation level of RSPO2 promoter decreased gradually. Inhibition of DNA methylation or DNMT1 knockdown could decrease the methylation level of CpG island (CGI) in RSPO2 promoter and upregulate the expression level of RSPO2 in porcine GCs. The hypomethylation of −758/−749 and −563/−553 regions in RSPO2 promoter facilitated the occupancy of transcription factor E2F1 and promoted the transcriptional activity of RSPO2. Moreover, RSPO2 promoted the proliferation of GCs with increasing the expression level of PCNA, CDK1, and CCND1 and promoted the E2 secretion of GCs with increasing the expression level of CYP19A1 and HSD17B1 and inhibited the apoptosis of GCs with decreasing the expression level of Caspase3, cleaved Caspase3, cleaved Caspase8, cleaved Caspase9, cleaved PARP, and BAX. In addition, RSPO2 knockdown promoted the apoptosis of GCs, blocked the development of follicles, and delayed the onset of puberty with decreasing the expression level of Wnt signaling pathway-related genes (LGR4 and CTNNB1) in vivo. Taken together, the hypomethylation of −758/−749 and −563/−553 regions in RSPO2 promoter facilitated the occupancy of E2F1 and enhanced the transcription of RSPO2, which further promoted the proliferation and E2 secretion of GCs, inhibited the apoptosis of GCs, and ultimately ameliorated the development of follicles through Wnt signaling pathway. This study will provide useful information for further exploration on DNA-methylation-mediated RSPO2 pathway during follicular development.

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Evaluation of MACF1-regulatory non-coding RNA as a potential therapeutic target in Colorectal Cancer

QJM ◽

10.1093/qjmed/hcab088.011 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Rowaida Mohammed Reda M. M Aboushahba ◽

Fayda Ibrahim Abdel Motaleb ◽

Ahmed Abdel Aziz Abou-Zeid ◽

Enas Samir Nabil ◽

Dalia Abdel-Wahab Mohamed ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Proliferation ◽

Wnt Signaling ◽

Cell Line ◽

Signaling Pathway ◽

Therapeutic Target ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Control Group ◽

Potential Therapeutic Target

ABSTRACT Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths world-wide. There is an increasing need for the identification of novel biomarkers/targets for early diagnosis and for the development of novel chemopreventive and therapeutic agents for CRC. Recently, MACF1 gene has emerged as a potential therapeutic target in cancer as it involved in processes critical for tumor cell proliferation, invasion and metastasis. It is suggested that MACF1 may function in cancers through Wnt signaling. MiR-34a is a well-known tumor suppressor miRNA.miR-34a targets MACF1 gene as a part of the wnt signaling pathway. In this study, 40 colonic tissues were collected from CRC patients (20) and control subjects (20). miR-34a-5p was assessed by real time PCR in all study groups. The results showed highly significant decrease (P < 0.01) in miR-34a relative expression in the CRC group (median RQ 0.13) when compared to the benign group (median RQ 5.3) and the healthy control group (median RQ 19.63). miR-34a mimic and inhibitor were transfected in CaCo-2 cell line and proliferation was assessed. The transfection of the cell line with miR-34a mimic decreased cell proliferation. Our study suggests that miR-34a-5p targets MACF1 gene as a part of the wnt signaling pathway leading to the involvement in the molecular mechanisms of CRC development and progression.

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Generating a Wnt switch: it’s all about the right dosage

The Journal of Cell Biology ◽

10.1083/jcb.201103167 ◽

2011 ◽

Vol 193 (3) ◽

pp. 431-433 ◽

Cited By ~ 20

Author(s):

Hans A. Kestler ◽

Michael Kühl

Keyword(s):

Wnt Signaling ◽

Signaling Pathway ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Wnt Proteins ◽

Cell Biol ◽

Tissue Patterning ◽

Wnt Ligands ◽

The Right

Wnt proteins can activate different branches of the Wnt signaling pathway, raising the question of specificity. In this issue, Nalesso et al. (2011. J. Cell Biol. doi:10.1083/jcb.201011051) provide an answer to this conundrum by showing that different concentrations of Wnt ligands can elicit different intracellular responses. These findings not only provide new insights into the molecular mechanisms underlying Wnt signaling, but also indicate how Wnt gradients might contribute to tissue patterning during embryogenesis.

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Folic Acid Exerts Dose-Dependent Biphasic Effects on Cardiac Development of Zebrafish Embryos

10.20944/preprints202109.0250.v1 ◽

2021 ◽

Author(s):

Xuhui Han ◽

Bingqi Wang ◽

Hongjie Wang ◽

Yao Zu

Keyword(s):

Folic Acid ◽

Methylenetetrahydrofolate Reductase ◽

Cardiac Development ◽

Mthfr Gene ◽

Folate Metabolism ◽

Marker Genes ◽

Zebrafish Embryos ◽

Cardiovascular Development ◽

Knock Out ◽

Dose Dependent

Folic acid, one of the 13 essential vitamins, plays an important role in cardiovascular development. Mutations in folic acid synthesis gene 5,10-methylenetetrahydrofolate reductase (MTHFR) is significantly associated with the occurrence of congenital heart disease. However, the mechanisms underlying the regulation of cardiac development by mthfr gene are poorly understood. Here, we exposed zebrafish embryos to excessive folate or folate metabolism inhibitors. And we established a knock-out mutant of mthfr gene in zebrafish by using CRISPR/Cas9. The zebrafish embryos of insufficient or excessive folic acid, and mthfr-/- mutant all gave rise to early pericardial edema and cardiac defect at 3 days after fertilization(dpf). Furthermore, the folic acid treated embryos showed abnormal movement at 5dpf. The expression levels of cardiac marker genes hand2, gata4 and nppa changed in the abnormality of folate metabolism embryos and mthfr-/- mutant, and there is evidence that they are related to the change of methylation level caused by the change of folate metabolism. In conclusion, our study provides a novel model for the in-depth study of MTHFR gene and folate metabolism. And our results reveal that folic acid has a dose-dependent biphasic effect on early cardiac development.

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Autophagy Is Required for Hepatic Differentiation of Hepatic Progenitor Cells via Wnt Signaling Pathway

BioMed Research International ◽

10.1155/2021/6627506 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Jianxing Zeng ◽

Yingying Jing ◽

Qionglan Wu ◽

Jinhua Zeng ◽

Lixin Wei ◽

...

Keyword(s):

Wnt Signaling ◽

Signaling Pathways ◽

Progenitor Cells ◽

Signaling Pathway ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Hepatic Progenitor Cells ◽

Hepatic Differentiation ◽

Development And Differentiation ◽

Progenitor Cell Line

The molecular mechanisms regulating differentiation of hepatic progenitor cells (HPCs), which play pivotal roles in liver regeneration and development, remain obscure. Autophagy and Wnt signaling pathways regulate the development and differentiation of stem cells in various organs. However, the roles of autophagy and Wnt signaling pathways in hepatic differentiation of HPCs are not well understood. Here, we describe the effects of autophagy and Wnt signaling pathways during hepatic differentiation of HPCs. We used a well-established rat hepatic progenitor cell line called WB-F344, which was treated with differentiation medium to promote differentiation of WB-F344 cells along the hepatic phenotype. Firstly, autophagy was highly activated in HPCs and gradually decreased during hepatic differentiation of HPCs. Induction of autophagy by rapamycin or starvation suppressed hepatic differentiation of HPCs. Secondly, Wnt3a signaling pathway was downregulated, and Wnt5a signaling pathway was upregulated in hepatic differentiation of HPCs. At last, Wnt3a signaling pathway was enhanced, and Wnt5a signaling pathway was inhibited by activation of autophagy during hepatic differentiation of HPCs. In summary, these results demonstrate that autophagy regulates hepatic differentiation of hepatic progenitor cells through Wnt signaling pathway.

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Striatal Synapse Degeneration and Dysfunction Are Reversed by Reactivation of Wnt Signaling

Frontiers in Synaptic Neuroscience ◽

10.3389/fnsyn.2021.670467 ◽

2021 ◽

Vol 13 ◽

Author(s):

Soledad Galli ◽

Stefka H. Stancheva ◽

Tom Dufor ◽

Alasdair J. Gibb ◽

Patricia C. Salinas

Keyword(s):

Wnt Signaling ◽

Wnt Pathway ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Complete Recovery ◽

Adult Brain ◽

Inhibitory Synapses ◽

Medium Spiny Neurons ◽

Dkk1 Expression ◽

Synapse Degeneration

Synapse degeneration in the striatum has been associated with the early stages of Parkinson’s and Huntington’s diseases (PD and HD). However, the molecular mechanisms that trigger synaptic dysfunction and loss are not fully understood. Increasing evidence suggests that deficiency in Wnt signaling triggers synapse degeneration in the adult brain and that this pathway is affected in neurodegenerative diseases. Here, we demonstrate that endogenous Wnt signaling is essential for the integrity of a subset of inhibitory synapses on striatal medium spiny neurons (MSNs). We found that inducible expression of the specific Wnt antagonist Dickkopf-1 (Dkk1) in the adult striatum leads to the loss of inhibitory synapses on MSNs and affects the synaptic transmission of D2-MSNs. We also discovered that re-activation of the Wnt pathway by turning off Dkk1 expression after substantial loss of synapses resulted in the complete recovery of GABAergic and dopamine synapse number. Our results also show that re-activation of the Wnt pathway leads to a recovery of amphetamine response and motor function. Our studies identify the Wnt signaling pathway as a potential therapeutic target for restoring neuronal circuits after synapse degeneration.

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Targeting Wnt Signaling through Small molecules in Governing Stem Cell Fate and Diseases

Endocrine Metabolic & Immune Disorders - Drug Targets ◽

10.2174/1871530319666190118103907 ◽

2019 ◽

Vol 19 (3) ◽

pp. 233-246 ◽

Cited By ~ 1

Author(s):

Antara Banerjee ◽

Ganesan Jothimani ◽

Suhanya Veronica Prasad ◽

Francesco Marotta ◽

Surajit Pathak

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Wnt Signaling ◽

Small Molecules ◽

Signaling Pathway ◽

Cell Fate ◽

Wnt Pathway ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Stem Cell Fate

Background:The conserved Wnt/β-catenin signaling pathway is responsible for multiple functions including regulation of stem cell pluripotency, cell migration, self-renewability and cell fate determination. This signaling pathway is of utmost importance, owing to its ability to fuel tissue repair and regeneration of stem cell activity in diverse organs. The human adult stem cells including hematopoietic cells, intestinal cells, mammary and mesenchymal cells rely on the manifold effects of Wnt pathway. The consequences of any dysfunction or manipulation in the Wnt genes or Wnt pathway components result in specific developmental defects and may even lead to cancer, as it is often implicated in stem cell control. It is absolutely essential to possess a comprehensive understanding of the inhibition and/ or stimulation of the Wnt signaling pathway which in turn is implicated in determining the fate of the stem cells.Results:In recent years, there has been considerable interest in the studies associated with the implementation of small molecule compounds in key areas of stem cell biology including regeneration differentiation, proliferation. In support of this statement, small molecules have unfolded as imperative tools to selectively activate and inhibit specific developmental signaling pathways involving the less complex mechanism of action. These compounds have been reported to modulate the core molecular mechanisms by which the stem cells regenerate and differentiate.Conclusion:This review aims to provide an overview of the prevalent trends in the small molecules based regulation of stem cell fate via targeting the Wnt signaling pathway.

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Regulation of BMP7 expression during kidney development

Development ◽

10.1242/dev.125.17.3473 ◽

1998 ◽

Vol 125 (17) ◽

pp. 3473-3482 ◽

Cited By ~ 8

Author(s):

R.E. Godin ◽

N.T. Takaesu ◽

E.J. Robertson ◽

A.T. Dudley

Keyword(s):

Wnt Signaling ◽

Kidney Development ◽

Tooth Development ◽

Expression Patterns ◽

Wnt Signaling Pathway ◽

Sodium Chlorate ◽

Bmp Signaling ◽

Proteoglycan Synthesis ◽

Metanephric Mesenchyme ◽

Ureteric Bud

Members of the Bone Morphogenetic Protein (BMP) family exhibit overlapping and dynamic expression patterns throughout embryogenesis. However, little is known about the upstream regulators of these important signaling molecules. There is some evidence that BMP signaling may be autoregulative as demonstrated for BMP4 during tooth development. Analysis of BMP7 expression during kidney development, in conjunction with studies analyzing the effect of recombinant BMP7 on isolated kidney mesenchyme, suggest that a similar mechanism may operate for BMP7. We have generated a beta-gal-expressing reporter allele at the BMP7 locus to closely monitor expression of BMP7 during embryonic kidney development. In contrast to other studies, our analysis of BMP7/lacZ homozygous mutant embryos, shows that BMP7 expression is not subject to autoregulation in any tissue. In addition, we have used this reporter allele to analyze the expression of BMP7 in response to several known survival factors (EGF, bFGF) and inducers of metanephric mesenchyme, including the ureteric bud, spinal cord and LiCl. These studies show that treatment of isolated mesenchyme with EGF or bFGF allows survival of the mesenchyme but neither factor is sufficient to maintain BMP7 expression in this population of cells. Rather, BMP7 expression in the mesenchyme is contingent on an inductive signal. Thus, the reporter allele provides a convenient marker for the induced mesenchyme. Interestingly LiCl has been shown to activate the Wnt signaling pathway, suggesting that BMP7 expression in the mesenchyme is regulated by a Wnt signal. Treatment of whole kidneys with sodium chlorate to disrupt proteoglycan synthesis results in the loss of BMP7 expression in the mesenchyme whereas expression in the epithelial components of the kidney are unaffected. Heterologous recombinations of ureteric bud with either limb or lung mesenchyme demonstrate that expression of BMP7 is maintained in this epithelial structure. Taken together, these data indicate that BMP7 expression in the epithelial components of the kidney is not dependent on cell-cell or cell-ECM interactions with the metanephric mesenchyme. By contrast, BMP7 expression in the metanephric mesenchyme is dependent on proteoglycans and possibly Wnt signaling.

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