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Keratin 17 (K17) is a stress-responsive intermediate filament protein that is upregulated in chronic skin diseases and in several carcinomas. We previously showed that K17 is induced in epidermal keratinocytes following exposure to DNA-damaging agents, promoting keratinocyte survival and chemically induced papilloma formation in mouse skin. Molecularly, K17 is recruited to the nucleus, where it impacts nuclear architecture, gene expression, and the DNA damage response (DDR). Here, we report on efforts to delineate K17-dependent processes during DDR by focusing on its interacting partners. Using mass spectrometry, we identified a network of K17-interacting Rho GTPase signaling proteins, including Rac1 and its activator Dock7. Biochemically, we confirmed that Rac1 and K17 interact directly in vitro and in A431 tumor keratinocytes, both at baseline and after ionizing radiation. We show that Show less

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired communication, abnormal social interactions, and restricted, repetitive behaviors. Pathogenic mutations in UBE3B result in neurodevelopmental disease, including intellectual disability, lack of speech, and ASD. UBE3B is an E3 ubiquitin ligase that tags substrate proteins with ubiquitin, marking them for proteasomal degradation. The ubiquitin-proteasome system (UPS) regulates several signaling pathways critical for neurodevelopment, including neurogenesis and synaptogenesis, and mutations in various UPS genes have been identified in ASD and related neurodevelopmental disorders. To investigate the function of UBE3B in the brain and how its disruption gives rise to neurodevelopmental abnormalities, we generated a central nervous system-specific conditional Ube3b knockout (cKO) mouse model and evaluated the resulting neurobehavioral phenotypes. We found that Ube3b cKO mice exhibit severe deficits in vocalization, social behavior, learning and memory, and motor skills. Assessment of in vivo neuronal phenotypes revealed defects in dendritic morphogenesis, reduced excitatory synapse density, diminished spontaneous cortical circuit activity, decreased AMPA receptor surface expression, and hyperexcitability of excitatory cortical neurons. Using quantitative proteomics, we profiled the proteome and ubiquitome of neural stem cells and identified 116 proteins that exhibited increased protein levels and reduced ubiquitination following loss of UBE3B. These proteins were highly enriched for ones involved in synaptic processes, and we confirmed interaction of UBE3B with several key synaptic proteins, including ATP1A1, DOCK7, NLGN2, and STX12. Collectively, our findings identify a role for UBE3B in regulating social, cognitive, and motor functions, and neuronal morphogenesis and activity by fine-tuning the synaptic proteome. Show less

Characterized by social communication deficits and the presence of restricted and repetitive behaviors, autism spectrum disorder (ASD) is a significant neurodevelopmental condition. Genetic studies have revealed a strong association between ASD and numerous mutations that alter the function of key proteins, either through activation or inactivation. These alterations are widely hypothesized to affect neuronal morphogenesis; however, a comprehensive understanding of the specific molecular cascades driving these cellular and symptomatic changes remains lacking. In this study, we report for the first time that signaling through the atypical Rho family guanine-nucleotide exchange factor (GEF) Dock7 and ErbB2, an activator acting upstream of Dock7, drives the excessive elongation of neuronal processes observed in association with the ASD- and intellectual disability (ID)-linked semaphorin-5A (Sema5A) Arg676Cys variant (p.Arg676Cys). Knockdown of Dock7 using short hairpin RNA or inhibition of ErbB2 kinase signaling with a specific chemical inhibitor reduced this excessive process elongation in primary cortical neurons. Similar results were obtained in the N1E-115 cell line, a neuronal cell model that undergoes neuronal morphological differentiation. Moreover, inhibition of ErbB2-Dock7 signaling specifically decreased the overactivation of the downstream molecules Rac1 and Cdc42. These findings indicate that the ErbB2-Dock7 signaling axis plays a role in mediating the aberrant neuronal morphology associated with the ASD- and ID-linked Sema5A p.Arg676Cys. Targeting this pathway may therefore offer a potential approach to addressing the molecular and cellular developmental challenges observed in ASD. Show less

Diabetes is a leading cause of death, affecting nearly half a billion adults worldwide. With projections indicating a significant increase in prevalence, understanding the genetic factors that contribute to diabetes, particularly type 2, is crucial. This study investigated the association of specific polymorphisms with type 2 diabetes (T2D) in the Uzbek population. A total of 165 individuals, including 125 patients with T2D and 40 controls, were genotyped for variants located in the The analysis revealed significant associations between these polymorphisms and T2D under various genetic models. The distribution of the genotype frequencies was consistent with the Hardy-Weinberg equilibrium. The findings of this study underscore the importance of ethnic and geographical diversity in genetic studies and contribute to the understanding of T2D in the Uzbek population. Further research is needed to explore the clinical implications of these genetic associations. Show less

Calcium-sensing receptor (CaSR), a G protein-coupled receptor, is overexpressed in certain breast cancer tumors where it drives cell migration and secretion of chemotactic agonists, likely contributing to metastatic dissemination. Since CaSR activates breast cancer cell migration via the Gβγ-PI3K-mTORC2/Rac-1 pathway, we hypothesized that PKCζ and perhaps other protein kinase C (PKC) isoforms, known as mTORC2-regulated effectors, are involved in migratory and invasive signaling elicited by CaSR. We analyzed the effect of PKC inhibitors and siRNAs which pointed to PKCζ as effector of CaSR in cell migration and invasion. In breast cancer phosphoproteomic CPTAC datasets, we identified a group of Luminal A subtype cancer patients having active PKCζ, according to its phosphorylation status at the turn motif. In addition, various phosphorylated RacGEFs, including TRIO, ARHGEF26, DOCK1 and DOCK7, clustered as phosphoproteins with active PKCζ. We therefore introduce atypical PKCζ as an effector component of the CaSR-Gβγ-PI3K-mTORC2 pathway in the activation of the promigratory small GTPase Rac. These results support ongoing initiatives to establish critical elements of the CaSR signaling pathway as potential targets in metastatic breast cancer. Show less

Cervical Squamous Cell Carcinoma and Endocervical Adenocarcinoma (CESC) is a highly prevalent female malignancy. As the epigenomic characteristics of immune cells and cancer cells can serve as predictive indicators for the response to cancer immunotherapy, analysis of epigenetically modified genes (EpiGenes) could contribute to CESC treatment. The ssGSEA algorithm was employed to compute EpiGenes scores. Core genes that exhibited significant module association and a close correlation with EpiGenes scores were identified via the WGCNA package. Univariate Cox proportional hazards regression was performed on the core genes using the survival package, followed by gene set reduction via LASSO Cox regression. Ultimately, key genes were determined through multivariate Cox regression to establish a RiskScore model. Further, the optimal risk cutoff was determined using the survminer package to stratify CESC patients into high- and low-risk subgroups. For enrichment analysis, clusterProfiler and GSEA were utilized. Immune infiltration across risk groups was evaluated via ssGSEA, the MCPcounter algorithm, and the ESTIMATE algorithm. TIDE was employed to compare immunotherapeutic responses between the risk groups, while the pRRophetic software was utilized to predict patients' chemotherapeutic drug sensitivity. The biomarkers identified were validated by performing in vitro experiments. CEP78, DOCK7, DPY19L4, and POM121 were identified by computational analyses as the key genes for CESC and further validated through in vitro experiments. Pathway enrichment analysis revealed predominant enrichment in immune-related pathways in the high-risk group, whereas the low-risk group was more enriched in energy and metabolic pathways. A significant negative correlation was observed between CD8+ T cell abundance and RiskScore, with higher ESTIMATEScores and StromalScores in high-risk patients. Notably, the high-risk group also demonstrated lower potential sensitivity to immunotherapy but more active responsiveness to a broader spectrum of chemotherapeutic agents. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that module genes are significantly enriched in cell cycle regulatory pathways, and these genes, in conjunction with Human Papillomavirus (HPV) infection-induced cell cycle dysregulation, jointly participate in CESC pathogenesis, providing a mechanistic basis for understanding the disease. This study provided novel theoretical evidence for immunotherapy and chemotherapy selection in the management of CESC. Show less

Chromatin accessibility and transcription levels during oocyte growth are important for oocyte maturation and subsequent development. However, chromatin accessibility changes in porcine oocytes during growth are unclear. The present study demonstrated that porcine oocytes derived from large follicles (LFO) exhibited higher developmental capacity than those derived from small follicles (SFO). Assay for transposase-accessible chromatin using sequencing (ATAC-seq) analysis identified 1117 and 1694 uniquely accessible chromatin peaks in LFO and SFO, respectively. Motif analysis of differential peaks revealed the top 10 significantly enriched transcription factor (TF)-binding motifs in LFO versus SFO, with only one increased peak (Spi1 binding site) and nine decreased peaks (NFYA, ATOH1, ZNF549, Foxn1, HAND2, THRB, NHLH2, FoxP1, and FoxP2 binding sites). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified key processes in the regulation of oocyte growth and maturation. Integration of ATAC-seq and RNA sequencing data revealed the top 10 hub genes involved in chromatin remodeling (MYSM1 and EZH2), histone modification (MYSM1, RNF2, USP1, EZH2, and MIER1), and transcription regulation (MYSM1, ASXL3, and MIER1), as well as those involved in metabolic processes and signal transduction (DOCK7, FGGY, DTL, and DNAJC6). All these genes exhibited increased expression levels in LFO versus SFO. In conclusion, the study demonstrated the dynamic nature of chromatin accessibility during porcine oocyte growth and revealed the TFs and genes closely associated with oocyte growth and maturation. These findings provide new insight into porcine oocyte growth and offer a potential strategy to enhance the in vitro developmental ability of SFO. Show less

Clinical studies have indicated a comorbidity between sepsis and kidney diseases. Individuals with specific mutations that predispose them to kidney conditions are also at an elevated risk for developing sepsis, and vice versa. This suggests a potential shared genetic etiology that has not been fully elucidated. Summary statistics data on exposure and outcomes were obtained from genome-wide association meta-analysis studies. We utilized these data to assess genetic correlations, employing a pleiotropy analysis method under the composite null hypothesis to identify pleiotropic loci. After mapping the loci to their corresponding genes, we conducted pathway analysis using Generalized Gene-Set Analysis of GWAS Data (MAGMA). Additionally, we utilized MAGMA gene-test and eQTL information (whole blood tissue) for further determination of gene involvement. Further investigation involved stratified LD score regression, using diverse immune cell data, to study the enrichment of SNP heritability in kidney-related diseases and sepsis. Furthermore, we employed Mendelian Randomization (MR) analysis to investigate the causality between kidney diseases and sepsis. In our genetic correlation analysis, we identified significant correlations among BUN, creatinine, UACR, serum urate, kidney stones, and sepsis. The PLACO analysis method identified 24 pleiotropic loci, pinpointing a total of 28 nearby genes. MAGMA gene-set enrichment analysis revealed a total of 50 pathways, and tissue-specific analysis indicated significant enrichment of five pairs of pleiotropic results in kidney tissue. MAGMA gene test and eQTL information (whole blood tissue) identified 33 and 76 pleiotropic genes, respectively. Notably, genes This study lays the groundwork for shared etiological factors between kidney and sepsis. The confirmed pleiotropic loci, shared pathogenic genes, and enriched pathways and immune cells have enhanced our understanding of the multifaceted relationships among these diseases. This provides insights for early disease intervention and effective treatment, paving the way for further research in this field. Show less

Metastasis accounts for the majority of deaths among patients with colorectal cancer (CRC). Here, the regulatory role of tumour-associated macrophages (TAMs) in CRC metastasis was explored. Immunohistochemical (IHC) analysis of the TAM biomarker CD163 was conducted to evaluate TAM infiltration in CRC. Transwell assays and an ectopic liver metastasis model were established to evaluate the metastatic ability of tumour cells. RNA sequencing (RNA-seq) and liquid chromatography-mass spectrometry (LC-MS) were applied to identify the differentially expressed genes and proteins in CRC cells and in TAM-derived extracellular vesicles (EVs). Cholesterol content measurement, a membrane fluidity assay and filipin staining were performed to evaluate cholesterol efflux in CRC cells. Our results showed that TAM infiltration is positively correlated with CRC metastasis. TAMs can facilitate the migration and invasion of MC-38 and CT-26 cells via EVs. According to the RNA-seq data, TAM-EVs increase cholesterol efflux and enhance membrane fluidity in CRC cells by regulating ABCA1 expression, thus affecting the motility of CRC cells. Mechanistically, DOCK7 packaged in TAM-EVs can activate RAC1 in CRC cells and subsequently upregulate ABCA1 expression by phosphorylating AKT and FOXO1. Moreover, IHC analysis of ABCA1 in patients with liver-metastatic CRC indicated that ABCA1 expression is significantly greater in metastatic liver nodules than in primary CRC tumours. Overall, our findings suggest that DOCK7 delivered via TAM-EVs could regulate cholesterol metabolism in CRC cells and CRC cell metastasis through the RAC1/AKT/FOXO1/ABCA1 axis. DOCK7 could thus be a new therapeutic target for controlling CRC metastasis. Show less

Aging is influenced by genetic determinants and comorbidities, among which diabetes increases the risk for heart failure with preserved ejection fraction. There is no therapy to prevent heart dysfunction in aging and diabetic individuals. In previous studies, a single administration of the longevity-associated variant (LAV) of the human BPIFB4 gene halted heart decline in older and type 2 diabetic mice. Here, we asked whether orally administered LAV-BPIFB4 protein replicates these benefits. In two controlled, randomized studies, 18-month-old male C57BL/6 J mice and 9-week-old C57BLKS/J-Leprdb/Leprdb/Dock7 + [db/db] mice of both sexes underwent baseline echocardiography. They then received a recombinant purified LAV-BPIFB4 protein (3 µg/animal, every three days) or vehicle by gavage. After 30 days, the animals underwent echocardiography, and the hearts were collected post-termination for histology. All the animals completed the study except one female diabetic mouse, which was culled prematurely because tooth malocclusion caused eating problems. There was no effect of the LAV-BPIFB4 protein on body weight in the two studies or glycosuria in the diabetic study. In aging mice, LAV-BPIFB4 increased myocardial Bpifb4 expression, improving heart contractility and capillarity while reducing perivascular fibrosis and senesce. In male diabetic mice, LAV-BPIFB4 therapy improved systolic function, microvascular density, and senescence, whereas the benefit was limited to systolic function in females. This study shows the feasibility and efficacy of a variant protein associated with human longevity in contrasting pivotal risk factors for heart failure in animal models. The diabetic study revealed that sex influences the treatment efficacy. Show less

The ability of cancer cells to survive microenvironmental stresses is critical for tumor progression and metastasis; however, how they survive these challenges is not fully understood. Here, we describe a novel multiprotein complex (DockTOR) essential for the survival of cancer cells under stress, triggered by the GTPase Cdc42 and a signaling partner Dock7, which includes AKT, mTOR, and the mTOR regulators TSC1, TSC2, and Rheb. DockTOR enables cancer cells to maintain a low but critical mTORC2-dependent phosphorylation of AKT during serum deprivation by preventing AKT dephosphorylation through an interaction between phospho-AKT and the Dock7 DHR1 domain. This activity stimulates a Raptor-independent but Rapamycin-sensitive mTOR/S6K activity necessary for survival. These findings address long-standing questions of how Cdc42 signals result in mTOR activation and demonstrate how cancer cells survive conditions when growth factor-dependent activation of mTORC1 is off. Determining how cancer cells survive stress conditions could identify vulnerabilities that lead to new therapeutic strategies. Show less

Tissue fluidification and collective motility are pivotal in regulating embryonic morphogenesis, wound healing and tumor metastasis. These processes frequently require that each cell constituent of a tissue coordinates its migration activity and directed motion through the oriented extension of lamellipodia cell protrusions, promoted by RAC1 activity. While the upstream RAC1 regulators in individual migratory cells or leader cells during invasion or wound healing are well characterized, how RAC1 is controlled in follower cells remains unknown. Here, we identify a novel MYO6-DOCK7 axis that is critical for spatially restriction of RAC1 activity in a planar polarized fashion in model tissue monolayers. The MYO6-DOCK7 axis specifically controls the extension of cryptic lamellipodia required to drive tissue fluidification and cooperative mode motion in otherwise solid and static carcinoma cell collectives. Collective motion of jammed epithelia requires myosin VI activityThe MYO6-DOCK7 axis is critical to restrict the activity of RAC1 in a planar polarized fashionMYO6-DOCK7-RAC1 activation ensures long-range coordination of movements by promoting orientation and persistence of cryptic lamellipodiaMyosin VI overexpression is exploited by infiltrating breast cancer cells. Show less

RAB3GAP1 is GTPase activating protein localized to the ER and Golgi compartments. In humans, mutations in RAB3GAP1 are the most common cause of Warburg Micro syndrome, a neurodevelopmental disorder associated with intellectual disability, microcephaly, and agenesis of the corpus callosum. We found that downregulation of RAB3GAP1 leads to a reduction in neurite outgrowth and complexity in human stem cell derived neurons. To further define the cellular function of RAB3GAP1, we sought to identify novel interacting proteins. We used a combination of mass spectrometry, co-immunoprecipitation and colocalization analysis and identified two novel interactors of RAB3GAP1: the axon elongation factor Dedicator of cytokinesis 7 (DOCK7) and the TATA modulatory factor 1 (TMF1) a modulator of Endoplasmic Reticulum (ER) to Golgi trafficking. To define the relationship between RAB3GAP1 and its two novel interactors, we analyzed their localization to different subcellular compartments in neuronal and non-neuronal cells with loss of RAB3GAP1. We find that RAB3GAP1 is important for the sub-cellular localization of TMF1 and DOCK7 across different compartments of the Golgi and endoplasmic reticulum. In addition, we find that loss of function mutations in RAB3GAP1 lead to dysregulation of pathways that are activated in response to the cellular stress like ATF6, MAPK, and PI3-AKT signaling. In summary, our findings suggest a novel role for RAB3GAP1 in neurite outgrowth that could encompass the regulation of proteins that control axon elongation, ER-Golgi trafficking, as well as pathways implicated in response to cellular stress. Show less

Pinpointing genetic impacts on DNA methylation can improve our understanding of pathways that underlie gene regulation and disease risk. We report heritability and methylation quantitative trait locus (meQTL) analysis at 724,499 CpGs profiled with the Illumina Infinium MethylationEPIC array in 2358 blood samples from three UK cohorts. Methylation levels at 34.2% of CpGs are affected by SNPs, and 98% of effects are cis-acting or within 1 Mbp of the tested CpG. Our results are consistent with meQTL analyses based on the former Illumina Infinium HumanMethylation450 array. Both SNPs and CpGs with meQTLs are overrepresented in enhancers, which have improved coverage on this platform compared to previous approaches. Co-localisation analyses across genetic effects on DNA methylation and 56 human traits identify 1520 co-localisations across 1325 unique CpGs and 34 phenotypes, including in disease-relevant genes, such as USP1 and DOCK7 (total cholesterol levels), and ICOSLG (inflammatory bowel disease). Enrichment analysis of meQTLs and integration with expression QTLs give insights into mechanisms underlying cis-meQTLs (e.g. through disruption of transcription factor binding sites for CTCF and SMC3) and trans-meQTLs (e.g. through regulating the expression of ACD and SENP7 which can modulate DNA methylation at distal sites). Our findings improve the characterisation of the mechanisms underlying DNA methylation variability and are informative for prioritisation of GWAS variants for functional follow-ups. The MeQTL EPIC Database and viewer are available online at https://epicmeqtl.kcl.ac.uk . Show less

Tissue fluidification and collective motility are pivotal in regulating embryonic morphogenesis, wound healing, and tumor metastasis. These processes frequently require that each cell constituent of a tissue coordinates its migration activity and directed motion through the oriented extension of lamellipodium cell protrusions, promoted by RAC1 activity. While the upstream RAC1 regulators in individual migratory cells or leader cells during invasion or wound healing are well characterized, how RAC1 is controlled in follower cells remains unknown. Here, we identify a MYO6-DOCK7 axis essential for spatially restricting RAC1 activity in a planar polarized fashion in model tissue monolayers. The MYO6-DOCK7 axis specifically controls the extension of cryptic lamellipodia required to drive tissue fluidification and cooperative-mode motion in otherwise solid and static carcinoma cell collectives. Show less

Childhood epilepsy is a common neurological disorder with a prevalence of 300-600 cases per 100,000 people. It is associated with refractory epilepsies, global developmental delay, and epileptic encephalopathies, causing epileptic syndromes characterized by cognitive and behavioral disorders. In this retrospective cohort study, patients with refractory epilepsy and global developmental delay, defined as epileptic encephalopathy, who applied to the Aydın 7Maternity and Children's Hospital Genetic Diagnosis Center and were followed in the pediatric neurology clinic of our hospital, between July 2018 and July 2021, were included. Targeted next-generation sequencing molecular genetics results were reviewed, and 3 ALDH7A1, 1 AARS, 3 CACNA1A, 1 CTNNB1, 1 DCX, 2 DBH, 2 DOCK7, 1 FOLR1, 2 GABRB3, 2 GCH1, 1 VGRIN2B, 1 GUF1, 3 KCNQ2, 2 KCNT1, 1 NECAP1, 1 PCDH19, 1 PNPO, 1 SCN8A, 1 SCN9A, 4 SCN1A, 2 SLC25A22, 1 SLC2A1, 2 SPTAN1, 2 SZT2, 4 TBC1D24, 2 TH, and 1 PCDH19 (X chromosome) mutations were detected in three of the patients using the next-generation sequencing method. Although the development of gene panels aids in diagnosis, there are still unidentified disorders in this illness category, which is highly variable in genotype and phenotype. Understanding the genetic etiology is vital for genetic counseling and, maybe, the future development of remedies for the etiology. Show less

The classical swine fever virus (CSFV) particle consists of three glycoproteins, all of which have been shown to be important proteins involved in many virus functions, including interaction with several host proteins. One of these proteins, E2, has been shown to be directly involved with adsorption to the host cell and important for virus virulence. Using the yeast two-hybrid system, we have previously shown that CSFV E2 specifically interacts with the (DOCK7) dedicator of cytokinesis, a scaffolding protein. In this report, the interaction between E2 and DOCK7 was evaluated. To confirm the yeast two-hybrid results and to determine that DOCK7 interacts in swine cells with E2, we performed co-immunoprecipitation and proximity ligation assay (PLA). After demonstrating the protein interaction in swine cells, E2 amino acid residues Y65, V283, and T149 were determined to be critical for interaction with Dock7 by using a random mutated library of E2 and a reverse yeast two-hybrid approach. That disruption of these three residues with mutations Y65F, V283D, and T149A abrogated the Dock7-E2 protein interaction. These mutations were then introduced into a recombinant CSFV, E2DOCK7v, by a reverse genomics approach using the highly virulent CSFV Brescia isolate as a backbone. E2DOCKv was shown to have similar growth kinetics in swine primary macrophages and SK6 cell cultures to the parental Brescia strain. Similarly, E2DOCK7v demonstrated a similar level of virulence to the parental Brescia when inoculated in domestic pigs. Animals intranasally inoculated with 10 Show less

Lysophosphatidic acid (LPA) species accumulate in the ascites of ovarian high-grade serous cancer (HGSC) and are associated with short relapse-free survival. LPA is known to support metastatic spread of cancer cells by activating a multitude of signaling pathways via G-protein-coupled receptors of the LPAR family. Systematic unbiased analyses of the LPA-regulated signal transduction network in ovarian cancer cells have, however, not been reported to date. Show less

Abdominal fat deposition depends on both the proliferation of preadipocytes and their maturation into adipocytes, which is a well-orchestrated multistep process involving many regulatory molecules. Circular RNAs (circRNAs) have emergingly been implicated in mammalian adipogenesis. However, circRNA-mediated regulation in chicken adipogenesis remains unclear. Our previous circRNA sequencing data identified a differentially expressed novel circRNA, 8:27,886,180|27,889,657, during the adipogenic differentiation of chicken abdominal preadipocytes. This study aimed to investigate the regulatory role of circDOCK7 in the proliferation and adipogenic differentiation of chicken abdominal preadipocytes, and explore its molecular mechanisms of competing endogenous RNA underlying chicken adipogenesis. Our results showed that 8:27,886,180|27,889,657 is an exonic circRNA derived from the head-to-tail splicing of exons 19-22 of the dedicator of cytokinesis 7 (DOCK7) gene, abbreviated as circDOCK7. CircDOCK7 is mainly distributed in the cytoplasm of chicken abdominal preadipocytes and is stable because of its RNase R resistance and longer half-life. CircDOCK7 is significantly upregulated in the abdominal fat tissues of fat chickens compared to lean chickens, and its expression gradually increases during the proliferation and adipogenic differentiation of chicken abdominal preadipocytes. Functionally, the gain- and loss-of-function experiments showed that circDOCK7 promoted proliferation, G0/G1- to S-phase progression, and glucose uptake capacity of chicken abdominal preadipocytes, in parallel with adipogenic differentiation characterized by remarkably increased intracellular lipid droplet accumulation and triglyceride and acetyl coenzyme A content in differentiated chicken abdominal preadipocytes. Mechanistically, a pull-down assay and a dual-luciferase reporter assay confirmed that circDOCK7 interacted with gga-miR-301b-3p, which was identified as an inhibitor of chicken abdominal adipogenesis. Moreover, the ACSL1 gene was demonstrated to be a direct target of gga-miR-301b-3p. Chicken ACSL1 protein is localized in the endoplasmic reticulum and mitochondria of chicken abdominal preadipocytes and acts as an adipogenesis accelerator. Rescue experiments showed that circDOCK7 could counteract the inhibitory effects of gga-miR-301b-3p on ACSL1 mRNA abundance as well as the proliferation and adipogenic differentiation of chicken abdominal preadipocytes. CircDOCK7 serves as a miRNA sponge that directly sequesters gga-miR-301b-3p away from the ACSL1 gene, thus augmenting adipogenesis in chickens. These findings may elucidate a new regulatory mechanism underlying abdominal fat deposition in chickens. Show less

Diabetes is known to delay wound healing, and this delay is attributed to prolonged inflammation. We found that microRNAs (miRNAs) might be involved in the dysfunction of diabetic-derived neutrophils, and dynamics of neutrophil and chronic inflammation might be initiated by miRNA-regulated genes. Moreover, studies of miRNA function in nephropathy have suggested that circular RNAs (circRNAs), which function as sponges of miRNA to regulate their expression, are potential biomarkers and new therapeutic targets for the diagnosis of diabetic nephropathy. Accordingly, to investigate the molecular mechanism of the regulation of inflammation in diabetic-derived neutrophils, we identified circRNAs in diabetic-derived neutrophils obtained from BKS.Cg- Show less

The epidermal growth factor receptor (EGFR) is a prime oncogene that is frequently amplified in glioblastomas. Here we demonstrate a new tumour-suppressive function of EGFR in EGFR-amplified glioblastomas regulated by EGFR ligands. Constitutive EGFR signalling promotes invasion via activation of a TAB1-TAK1-NF-κB-EMP1 pathway, resulting in large tumours and decreased survival in orthotopic models. Ligand-activated EGFR promotes proliferation and surprisingly suppresses invasion by upregulating BIN3, which inhibits a DOCK7-regulated Rho GTPase pathway, resulting in small hyperproliferating non-invasive tumours and improved survival. Data from The Cancer Genome Atlas reveal that in EGFR-amplified glioblastomas, a low level of EGFR ligands confers a worse prognosis, whereas a high level of EGFR ligands confers an improved prognosis. Thus, increased EGFR ligand levels shift the role of EGFR from oncogene to tumour suppressor in EGFR-amplified glioblastomas by suppressing invasion. The tumour-suppressive function of EGFR can be activated therapeutically using tofacitinib, which suppresses invasion by increasing EGFR ligand levels and upregulating BIN3. Show less

Early infantile epileptic encephalopathy (EIEE) is a severe neurologic and neurodevelopmental disease that manifests in the first year of life. It shows a high degree of genetic heterogeneity, but the genetic origin is only identified in half of the cases. We report the case of a female child initially diagnosed with Leber congenital amaurosis (LCA), an early-onset retinal dystrophy due to photoreceptor cell degeneration in the retina. The first examination at 9 months of age revealed no reaction to light or objects and showed wandering eye movements. Ophthalmological examination did not show any ocular abnormalities. The patient displayed mildly dysmorphic features and a global developmental delay. Brain MRI demonstrated pontine hypo-/dysplasia. The patient developed myoclonic epileptic seizures and epileptic spasms with focal and generalized epileptiform discharges on electroencephalogram (EEG) at the age of 16 months. Genetic screening for a potentially pathogenic DNA sequence variant by whole-exome sequencing (WES) revealed a novel, conserved, homozygous frameshift variant (c.5391delA, p.(Ala1798Leu Show less

Reading Disability (RD) is often characterized by difficulties in the phonology of the language. While the molecular mechanisms underlying it are largely undetermined, loci are being revealed by genome-wide association studies (GWAS). In a previous GWAS for word reading (Price, 2020), we observed that top single-nucleotide polymorphisms (SNPs) were located near to or in genes involved in neuronal migration/axon guidance (NM/AG) or loci implicated in autism spectrum disorder (ASD). A prominent theory of RD etiology posits that it involves disturbed neuronal migration, while potential links between RD-ASD have not been extensively investigated. To improve power to identify associated loci, we up-weighted variants involved in NM/AG or ASD, separately, and performed a new Hypothesis-Driven (HD)-GWAS. The approach was applied to a Toronto RD sample and a meta-analysis of the GenLang Consortium. For the Toronto sample (n = 624), no SNPs reached significance; however, by gene-set analysis, the joint contribution of ASD-related genes passed the threshold (p~1.45 × 10 Show less

Conjugated linoleic acid (CLA) can prevent fatty acid accumulation induced by a high-fructose diet and improve lipid metabolism disorders in patients. We aimed to investigate the effect of CLA on obesity and lipid metabolism and its possible mechanism. Eight-month-old male BKS.Cg-Dock7 CLA treatment notably reduced the dietary and water intake of db/db mice, effectively reduced body weight, and decreased serum TG and TC levels (p < 0.05). Increased expression of PPARα (p < 0.05) and decreased expression of CD36 (p < 0.001) were observed in the liver of mice that were fed CLA. CLA increased PPARα expression (p < 0.001) and decreased PPARγ (p < 0.001) and CD36 expression (p < 0.01) in HepG2 cells. Our results showed that CLA can improve lipid metabolism in obese mice through upregulation of PPARα expression and downregulation of CD36 expression. Show less

Diabetic wounds account for 25 to 50 percent of total diabetic health care costs annually, and present overall healing rates of less than 50 percent. Because delayed diabetic wound healing is associated with impaired fibroblast function, the authors hypothesize that tyrosine kinase Met (cMet) agonistic monoclonal antibody will promote diabetic wound healing by means of stable activation of hepatocyte growth factor/cMet signaling. Two 6-mm dorsal wounds were created in each mouse (6-week-old, male BKS.Cg-Dock7 m +/+Lepr db /J; n = 5). After subcutaneous injections of agonist (20 mg/kg) at 0 and 72 hours, the wound sizes were measured at days 0, 1, 3, 6, and 10. Histologic and immunohistochemical analyses were performed at day 10 (cMet, α-smooth muscle actin, CD68, and transforming growth factor-β). In vitro cytotoxicity and migration tests with diabetic fibroblasts were performed with or without agonist treatment (1 or 10 nM). cMet pathway activation of fibroblasts was confirmed through p-p44/42 mitogen-activated protein kinase, p-mTOR, p-cMet, and ROCK-1 expression. The cMet agonistic monoclonal antibody-treated group showed 1.60-fold lower wound area ( p = 0.027), 1.54-fold higher collagen synthesis ( p = 0.001), and 1.79-fold lower inflammatory cell infiltration ( p = 0.032) than the saline-treated control. The agonist increased cMet (1.86-fold; p = 0.029), α-smooth muscle actin (1.20-fold; p = 0.018), and vascular endothelial growth factor (1.68-fold, p = 0.029) expression but suppressed CD68 (1.25-fold; p = 0.043), transforming growth factor-β (1.25-fold; p = 0.022), and matrix metalloproteinase-2 (2.59-fold; p = 0.029) expression. In vitro agonist treatment (10 nM) of diabetic fibroblasts increased their migration by 8.98-fold ( p = 0.029) and activated the hepatocyte growth factor/cMet pathway. Tyrosine kinase Met agonistic monoclonal antibody treatment improved diabetic wound healing in mice and reduced wound-site inflammatory cell infiltration. These results need to be validated in large animals before piloting human trials. Although further clinical studies are necessary to evaluate its therapeutic efficacy, our study suggested that cMet agonistic monoclonal antibody can be the alternative modality in order to improve wound healing cascade in diabetic foot patients. Show less

ANGPTL3 is an important regulator of lipid metabolism. Its inhibition in people with hypercholesteremia reduces plasma lipid levels dramatically. Genome-wide association studies have associated ANGPTL3 variants with lipid traits. Irisin, an exercise-modulated protein, has been associated with lipid metabolism. Intracellular accumulation of lipids impairs insulin action and contributes to metabolic disorders. In this study, we evaluate the impact of ANGPTL3 variants on levels of irisin and markers associated with lipid metabolism and insulin resistance. ANGPTL3 rs1748197 and rs12130333 variants were genotyped in a cohort of 278 Arab individuals from Kuwait. Levels of irisin and other metabolic markers were measured by ELISA. Significance of association signals was assessed using Bonferroni-corrected Show less

RPA is a critical factor for DNA replication and replication stress response. Surprisingly, we found that chromatin RPA stability is tightly regulated. We report that the GDP/GTP exchange factor DOCK7 acts as a critical replication stress regulator to promote RPA stability on chromatin. DOCK7 is phosphorylated by ATR and then recruited by MDC1 to the chromatin and replication fork during replication stress. DOCK7-mediated Rac1/Cdc42 activation leads to the activation of PAK1, which subsequently phosphorylates RPA1 at S135 and T180 to stabilize chromatin-loaded RPA1 and ensure proper replication stress response. Moreover, DOCK7 is overexpressed in ovarian cancer and depleting DOCK7 sensitizes cancer cells to camptothecin. Taken together, our results highlight a novel role for DOCK7 in regulation of the replication stress response and highlight potential therapeutic targets to overcome chemoresistance in cancer. Show less