Dishevelled Binding Antagonist Of Beta Catenin 1 Research Articles

Heterozygous variants in the DVL2 interaction region of DACT1 cause CAKUT and features of Townes–Brocks syndrome 2

Most patients with congenital anomalies of the kidney and urinary tract (CAKUT) remain genetically unexplained. In search of novel genes associated with CAKUT in humans, we applied whole-exome sequencing in a patient with kidney, anorectal, spinal, and brain anomalies, and identified a rare heterozygous missense variant in the DACT1 (dishevelled binding antagonist of beta catenin 1) gene encoding a cytoplasmic WNT signaling mediator. Our patient’s features overlapped Townes–Brocks syndrome 2 (TBS2) previously described in a family carrying a DACT1 nonsense variant as well as those of Dact1-deficient mice. Therefore, we assessed the role of DACT1 in CAKUT pathogenesis. Taken together, very rare (minor allele frequency ≤ 0.0005) non-silent DACT1 variants were detected in eight of 209 (3.8%) CAKUT families, significantly more frequently than in controls (1.7%). All seven different DACT1 missense variants, predominantly likely pathogenic and exclusively maternally inherited, were located in the interaction region with DVL2 (dishevelled segment polarity protein 2), and biochemical characterization revealed reduced binding of mutant DACT1 to DVL2. Patients carrying DACT1 variants presented with kidney agenesis, duplex or (multi)cystic (hypo)dysplastic kidneys with hydronephrosis and TBS2 features. During murine development, Dact1 was expressed in organs affected by anomalies in patients with DACT1 variants, including the kidney, anal canal, vertebrae, and brain. In a branching morphogenesis assay, tubule formation was impaired in CRISPR/Cas9-induced Dact1−/− murine inner medullary collecting duct cells. In summary, we provide evidence that heterozygous hypomorphic DACT1 variants cause CAKUT and other features of TBS2, including anomalies of the skeleton, brain, distal digestive and genital tract.

Rapid semen identification from mixed body fluids using methylation-sensitive high-resolution melting analysis of the DACT1 gene.

In forensic genetics, a suspect is assigned to a component of a DNA mixture profile, and a probabilistic interpretation is then usually performed. However, it is difficult to determine what types of body fluid the component is from. Previous studies have reported that the fourth exon of the Dishevelled binding antagonist of beta catenin 1 (DACT1) gene is hypomethylated in a semen DNA-specific manner. In the present study, we evaluated whether the DACT1 gene could be effectively used to identify semen in body fluid mixtures and were able to semi-quantify the semen DNA content in mixed fluids. Our results showed that the DACT1 gene was useful in discriminating semen from venous blood and saliva. However, the amount of sperm in semen can affect semen identification. In addition, SI (the semen DNA content index), which we developed, was useful to determine whether the semen compromised majority, almost half, or was in the minority of the components in a mixed fluid. This technique is based on the methylation-sensitive high-resolution melting (MS-HRM) technology, which is time-, cost-, and labour-effective, and could be adopted in routine criminal investigations.

DACT1 Involvement in the Cytoskeletal Arrangement of Cardiomyocytes in Atrial Fibrillation by Regulating Cx43.

ObjectiveTo determine the role of the dishevelled binding antagonist of beta catenin 1 (DACT1) in the cytoskeletal arrangement of cardiomyocytes in atrial fibrillation (AF).MethodsThe DACT1 expression and its associations with the degree of fibrosis and β-catenin in valvular disease patients were analyzed by immunohistochemistry and Masson’s staining. DACT1 was overexpressed in the atrial myocyte cell line (HL-1) and the cardiac cell line (H9C2) by adenoviral vectors. Alterations in the fibrous actin (F-actin) content and organization and the expression of β-catenin were detected by flow cytometry, immunofluorescence, and Western blotting. Additionally, the association of DACT1 with gap junctions connexin 43 (Cx43) was detected by immunohistochemistry, immunofluorescence, and Western blotting.ResultsDecreased cytoplasmic DACT1 expression in the myocardium was associated with AF (P=0.037) and a high degree of fibrosis (weak vs. strong, P=0.028; weak vs. very strong, P=0.029). A positive association was observed between DACT1 and β-catenin expression in clinical samples (P=0.028, Spearman’s rho=0.408). Furthermore, overexpression of DACT1 in HL-1 and H9C2 cells induced an increase in β-catenin and subsequent partial colocalization of DACT1 and β-catenin. In addition, F-actin content and organization were enhanced. Interestingly, DACT1 was positively correlated with the Cx43 expression in clinical samples (P=0.048, Spearman’s rho=0.370) and changed the Cx43 distribution in cardiac cell lines.ConclusionDACT1 proved to be a novel AF-related gene by regulating Cx43 via cytoskeletal organization induced by β-catenin accumulation in cardiomyocytes. DACT1 could thus serve as a potential therapeutic marker for AF.

MiR-124 promotes proliferation and neural differentiation of neural stem cells through targeting DACT1 and activating Wnt/β-catenin pathways.

Neural stem cells (NSCs) are multipotent and undifferentiated cells with the potential to differentiate into neuronal lineages and gliocytes. NSCs have the ability to generate and regenerate the brain, indicating the possibility of cell-based therapies for neurological disorders. miR-124 has been demonstrated as a modulator in the survival, expansion, and differentiation of NSCs. However, the underlying molecular mechanisms of miR-124 in NSC development are still far from being understood. The expressions of miR-124, dishevelled binding antagonist of beta-catenin 1 (DACT1), ki-67, Nestin, β-tubulin III, glial fibrillary acidic protein (GFAP), β-catenin, cyclinD1, and glycogen synthase kinase-3β (GSK-3β) were examined by qRT-PCR or western blot. Bioinformatics and Dual-Luciferase reporter assay were used to identify the interaction between miR-124 and DACT1. MTS analysis was performed to measure the viability of NSCs. Enhanced expression of miR-124 and lowered expression of DACT1 were observed during a 14-day NSC differentiation period. DACT1 was verified as a direct target of miR-124. Moreover, overexpression of miR-124 promoted NSC proliferation and induced neuron-specific differentiation, presented as increased cell viability, higher neurosphere number, elevated ki-67, Nestin, β-tubulin III expressions, and decreased GFAP expression. Similarly, DACT1 downregulation facilitated proliferation and neuronal differentiation of NSCs. Furthermore, DACT1 overexpression impaired miR-124-induced proliferation and differentiation of NSCs. Additionally, miR-124 stimulated Wnt/β-catenin signaling via suppressing DACT1 expression. miR-124 promoted proliferation and induced NSC differentiation to neurons by activation of Wnt/β-catenin pathway via targeting DACT1, providing a potential target and aiding the development of cell-based therapies for neurological disorders.

MiR-324-3p promotes tumor growth through targeting DACT1 and activation of Wnt/β-catenin pathway in hepatocellular carcinoma.

Recently, it has been reported that miR-324-3p participates in regulation of the carcinogenesis and tumor progression in various cancers. However, the expression and function of miR-324-3p in hepatocellular carcinoma (HCC) remain unclear. In the current study, miR-324-3p expression was significantly up-regulated in HCC tissues and cell lines. HCC patients with high miR-324-3p level showed poor prognostic features and shorter overall survival and disease-free survival. And in vitro and in vivo experiments revealed that miR-324-3p promoted cell viability, colony formation, proliferation and cell cycle progression of HCC cells. Further studies demonstrated that miR-324-3p could directly target DACT1 (dishevelled binding antagonist of beta catenin 1) and negatively regulated its expression in HCC cells. And rescue experiments revealed that DACT1 could reverse the effects of miR-324-3p on HCC cells. Furthermore, the accumulation of both cytoplasmic and nuclear β-catenin as well as its downstream targets including c-Myc and cyclin D1 could be positively regulated by miR-324-3p. The regulatory effects of miR-324-3p on β-catenin, c-Myc and cyclin D1 levels could be reversed by DACT1. Overall, we concluded that miR-324-3p could promote tumor growth through targeting DACT1 and activation of Wnt/β-catenin pathway in HCC. MiR-324-3p may be a ponderable and promising therapeutic target for HCC.