Search Results (177)

Congenital Anomalies of the Kidney and Urinary Tract (CAKUT) are among the most common congenital malformations and the leading cause of chronic kidney disease in children. They arise when key steps in kidney development are disrupted, including ureteric bud induction, branching morphogenesis and nephron progenitor differentiation. These processes depend on coordinated transcriptional programs, signaling pathways, ciliary function and proper extracellular matrix (ECM) organization. Advances in whole exome and whole genome sequencing, as well as copy number variation analysis, have expanded the spectrum of known monogenic causes. Pathogenic variants have now been identified in major transcriptional regulators and multiple ciliopathy-related genes. Evidence also points to defects in central signaling pathways and changes in ECM composition as contributors to CAKUT pathogenesis. Clinical presentations vary widely, shaped by modifying effects of genetic background, epigenetic regulation and environmental influences such as maternal diabetes and fetal hypoxia. Emerging tools, including human kidney organoids, gene-editing approaches and single-cell or spatial transcriptomics, allow detailed exploration of developmental mechanisms and validation of candidate pathways. Overall, CAKUT reflects a multifactorial condition shaped by interacting genetic, epigenetic and environmental determinants. Integrating genomic data with experimental models is essential for improving diagnosis, deepening biological insight and supporting the development of targeted therapeutic strategies. Full article

Sesquiterpene lactones (SLs) are plant-derived metabolites with recognized pharmacological properties. Dysfunction of the primary cilium (PC), a solitary sensory organelle essential for development, is associated with disorders such as ciliopathies and tumors. While previous studies have shown that certain SLs can alter PC structure in human retinal cells, their influence on ciliary signaling pathways remains unclear. In this study, we examined the effect of four SLs—grosheimin, costunolide, α-cyclocostunolide (α-C), and β-cyclocostunolide (β-C)—on ciliary function in human primary fibroblasts. Using immunofluorescence and qPCR to assess cilia structure and Hedgehog (Hh) pathway activation, we found that grosheimin enhanced ciliogenesis without affecting Hh signaling. In contrast, costunolide, α-C, and β-C disrupted ciliary structure and suppressed the Hh pathway transcripts Gli1 and Ptch1. RNA sequencing revealed that grosheimin upregulated genes related to microtubule binding and ciliogenesis, whereas α-C downregulated tubulin subunit transcripts. These findings suggest distinct molecular mechanisms through which SLs affect ciliary structure and function. Collectively, this study highlights the potential of specific SLs as modulators of ciliary signaling, offering promising leads for therapeutic strategies targeting ciliopathies and tumors. Full article

Primary ciliary dyskinesia (PCD) is a rare hereditary disorder belonging to the group of ciliopathies, with autosomal recessive, autosomal dominant, and, less frequently, X-linked inheritance patterns. The aim of this study was to investigate the genetic heterogeneity of the Russian population of PCD patients based on national registry data. The study included patients with PCD confirmed by molecular genetic testing. Quantitative data were analyzed using non-parametric statistical methods. Differences were considered statistically significant at p < 0.05. The study included 109 patients with PCD. Molecular genetic testing identified pathogenic variants in 29 autosomal recessive genes. The analysis of pathogenic variant distribution in the Russian PCD cohort revealed the highest number of changes in the DNAH5 and DNAH11 genes. 26 genetic variants in 13 genes were identified for the first time in the Russian population. Variants in the DNAH5 gene were significantly more frequent in Kartagener’s syndrome (KS) patients (32/55%) compared to those without KS (11/21.5%) (χ² = 12.8; p = 0.0004; OR = 4.48). Preliminary data indicate that the frequency spectrum of DNAH5 and DNAH11 genes in Russian patients is similar to international trends. Additionally, there is an accumulation of pathogenic variants in the DNAH5, DNAH11, CCDC39, and CFAP300 genes. Full article

Alström (ALMS) and Bardet-Biedl syndromes (BBS) are rare ciliopathies characterized by obesity and hyperglycemia that lead to type 2 diabetes, but also other disorders, including neurodegeneration. However, isolated clinical manifestations can be observed in carriers of heterozygous mutations in the ALMS1 and BBS genes. Recently, the influence of oral bacteria on the presence of obesity, type 2 diabetes, and neurodegenerative processes has been widely discussed. The purpose of the research project was to analyze the profile of the microbiome in the oral cavity by sequencing the 16S rRNA gene in ALMS/BBS patients and carriers of causative variants in these genes. Oral mucosal swabs were taken from 8 ALMS/BBS patients, 24 family members, 20 obese patients, and 29 healthy individuals. Streptococcus (30.7%), Haemophilus (18.9%), and Prevotella (11%) were the most common bacteria in the study group. Comparison between groups showed a higher abundance of Prevotella, Enterococcus, Eikenella, Capnocytophaga, Parvimonas, Selenomonas, and Corynobacterium, and a lower abundance of Lactobacillus in the study group compared to other groups. The specific profile of the oral microbiome found in patients with variants in the ALMS1 and BBS genes may enable the identification of the modulatory role of the oral microbiome in these disorders and point to new directions for additional therapy for these patients and heterozygous family members in the future. Full article

The primary cilium is generally viewed as a sensory organelle that transduces chemical and mechanical stimuli from the environment. In the adult hippocampus, primary cilia mediate the effects of sonic hedgehog (Shh) and other signals on neurogenesis and hippocampal function, and loss of cilia leads to cognitive and behavioral deficits. The secreted peptide noggin is a bone morphogenetic protein (BMP) antagonist and plays a critical role in regulating adult hippocampal neurogenesis (AHN) and hippocampus-dependent behavior. Here, we show that noggin is expressed by mature granule cell neurons, that it is apically targeted and localized intracellularly near the pocket region of primary cilia, and that cilia regulate noggin release through Shh and somatostatin (SST) pathways. Further, granule cell activation modulates noggin dynamics both in vitro and in vivo. Together, these findings demonstrate synergy between Shh and noggin and the positive regulatory action of neuronal activity on regulating BMP antagonism within the neurogenic niche. Thus, the primary cilium is not only an organelle that transduces signals to neurons but also one that mediates extracellular signaling. Significance statement: Primary cilia are organelles that protrude from the surface of most vertebrate cell types. Defects in primary ciliary structure and function are associated with human disease. Primary cilia are generally viewed as exclusively sensory organelles that respond to environmental signals to regulate both cell development and adult cell function. This study demonstrates that the primary cilia in hippocampal granule cell neurons mediate the release of the BMP antagonist, noggin. These observations expand the current understanding of ciliary signaling and may inform future studies exploring the connection between hippocampal activity and cognition in ciliopathies. Full article

Given that type 2 diabetes mellitus is common in several ciliopathies, the NME7 gene (non-metastatic cells 7), encoding a recognized member of the ciliome, was studied in connection with glucose metabolism. The aim was to find out whether the variability in the gene is associated with the response to administered glucose during the 3 h oral glucose tolerance test. The study included 1262 individuals with different levels of glucose tolerance. Glycemic curves were categorized according to their shape as monophasic, biphasic, triphasic, and more complex multiphasic. The analysis showed a significant association of five linked NME7 polymorphisms with the biphasic course of the glycemic curve, a shape that has been shown to be metabolically protective. Specifically, minor alleles of rs4656659 and rs2157597 in combination with wild-type alleles of rs10732287, rs4264046, and rs10800438 were more frequent within the biphasic category. Moreover, haplotype analysis confirmed higher insulin sensitivity in carriers of this specific haplotype. In conclusion, a cluster of five linked NME7 polymorphisms showed an association with a biphasic glycemic curve. Considering the health benefits of the biphasic curve in terms of glycoregulation and taking into account the demonstrated link of the NME7 haplotype with insulin sensitivity, variability in the NME7 gene represents another piece of the complex mosaic influencing healthy energy processing. Full article

The Never-in-Mitosis A-Related Kinase (NEK) family is an important, yet largely understudied, family of protein kinases involved in the regulation of a variety of critical cellular processes. Consequently, dysregulation of NEK function has been linked to the etiology and progression of several disorders, including cancer, ciliopathies, neurodegenerative disorders, inflammatory disorders, and other pervasive diseases. In this review, we have summarized recent findings to provide an overview of the NEK family and their diverse functions within various cellular contexts. In parallel, we have highlighted the emerging roles of NEK family members in human health, identifying potential therapeutic targets within the NEK family and exploring their potential for future clinical applications. Finally, we have addressed ongoing challenges and emerging research directions in this rapidly evolving field, aiming to pave the way for future discoveries and innovations. Full article

Smell dysfunction affects quality of life and is considered an early clinical sign of Alzheimer’s and Parkinson’s diseases. Olfactory loss increases with age and is associated with certain ciliopathies, a group of genetic disorders characterized by a wide spectrum of multisystemic disturbances. The dysfunction of mature olfactory sensory neurons (OSNs) in the olfactory neuronal pathway remains poorly understood. Previous evidence suggests that primary cilia proteins are involved in the maturation of olfactory sensory neurons (OSNs). In this study, we obtained olfactory neuronal precursors (ONPs) from the olfactory mucosa of young and older healthy volunteers who reported smell impairment (hyposmia) without neurological deficits or underlying airflow issues (conductive olfactory loss) and from normosmic individuals. In vitro analysis of ONPs showed that these cells can form primary cilia in normosmic individuals, while in hyposmic participants, there is a reduction in cilia frequency and a shorter length. In addition, ONPs from hyposmic individuals had a decrease in proliferation and cell differentiation. Our data indicate that alterations in molecular pathways related to primary cilia formation and the proliferation of ONPs lead to defects in neuronal maturation. These changes may hinder the differentiation of olfactory sensory neurons OSNs and contribute, at least in part, to olfactory loss. Full article

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a systemic ciliopathy resulting from loss-of-function mutations in the PKD1 and PKD2 genes, which encode polycystin-1 (PC1) and polycystin-2 (PC2), respectively. PC1 and PC2 regulate mechanosensation, calcium signaling, and key pathways controlling tubular epithelial structure and function. Loss of PC1/PC2 disrupts calcium homeostasis, elevates cAMP, and activates proliferative cascades such as PKA–B-Raf–MEK–ERK, mTOR, and Wnt, driving cystogenesis via epithelial proliferation, impaired apoptosis, fluid secretion, and fibrosis. Recent evidence also implicates novel signaling axes in ADPKD progression including, the Hippo pathway, where dysregulated YAP/TAZ activity enhances c-Myc-mediated proliferation; the stimulator of interferon genes (STING) pathway, which is activated by mitochondrial DNA release and linked to NF-κB-driven inflammation and fibrosis; and the TWEAK/Fn14 pathway, which mediates pro-inflammatory and pro-apoptotic responses via ERK and NF-κB activation in tubular cells. Mitochondrial dysfunction, oxidative stress, and maladaptive extracellular matrix remodeling further exacerbate disease progression. A refined understanding of ADPKD’s complex signaling networks provides a foundation for precision medicine and next-generation therapeutics. This review gathers recent molecular insights and highlights both established and emerging targets to guide targeted treatment strategies in ADPKD. Full article

Sperm flagellum defects are tightly associated with male infertility. Centriolar satellites are small multiprotein complexes that recruit satellite proteins to the centrosome and play an essential role in sperm flagellum biogenesis, but the precise mechanisms underlying this role remain unclear. Serologically defined colon cancer autoantigen protein 8 (SDCCAG8), which encodes a protein containing eight coiled-coil (CC) domains, has been associated with syndromic ciliopathies and male infertility. However, its exact role in male infertility remains undefined. Here, we used an Sdccag8 mutant mouse carrying a CC domains 5–8 truncated mutation (c.1351–1352insG p.E451GfsX467) that models the mutation causing Senior–Løken syndrome (c.1339–1340insG p.E447GfsX463) in humans. The homozygous Sdccag8 mutant mice exhibit male infertility characterized by multiple morphological abnormalities of the flagella (MMAF) and dysmorphic structures in the sperm manchette. A mechanistic study revealed that the SDCCAG8 protein is localized to the manchette and centrosomal region and interacts with PCM1, the scaffold protein of centriolar satellites, through its CC domains 5–7. The absence of the CC domains 5–7 in mutant spermatids destabilizes PCM1, which fails to recruit satellite components such as Bardet–Biedl syndrome 4 (BBS4) and centrosomal protein of 131 kDa (CEP131) to satellites, resulting in defective sperm flagellum biogenesis, as BBS4 and CEP131 are essential to flagellum biogenesis. In conclusion, this study reveals the central role of SDCCAG8 in maintaining centriolar satellite integrity during sperm flagellum biogenesis. Full article

Centriole duplication is a vital process for cellular organisation and function, underpinning essential activities such as cell division, microtubule organisation and ciliogenesis. This review summarises the latest research on the mechanisms and regulatory pathways that control this process, focusing on important proteins such as polo-like kinase 4 (PLK4), SCL/TAL1 interrupting locus (STIL) and spindle assembly abnormal protein 6 (SAS-6). This study examines the complex steps involved in semi-conservative duplication, from initiation in the G1–S phase to the maturation of centrioles during the cell cycle. Additionally, we will explore the consequences of dysregulated centriole duplication. Dysregulation of this process can lead to centrosome amplification and subsequent chromosomal instability. These factors are implicated in several cancers and developmental disorders. By integrating recent study findings, this review emphasises the importance of centriole duplication in maintaining cellular homeostasis and its potential as a therapeutic target in disease contexts. The presented findings aim to provide a fundamental understanding that may inform future research directions and clinical interventions related to centriole biology. Full article

Sensenbrenner syndrome, or cranioectodermal dysplasia (CED), is a rare autosomal recessive ciliopathy characterized by craniofacial, skeletal, ectodermal, and renal abnormalities. Ocular involvement, though infrequent, can include retinal dystrophy with early-onset visual impairment. We report a case of a 2-year-old boy with classic clinical features of CED and significant ocular findings. Genetic testing revealed two novel compound heterozygous variants in the WDR19 gene—c.1778G>T and c.3536T>G—expanding the known mutational spectrum associated with this condition. Ophthalmologic evaluation demonstrated bilateral optic nerve hypoplasia, high hyperopia, and severely reduced ERG responses, consistent with global retinal dysfunction. Fundoscopy revealed optic disk pallor, vessel attenuation, and peripheral pigment changes. Multisystem findings included postaxial polydactyly, brachydactyly, short stature, hypotonia, and stage 2 chronic kidney disease. This case highlights the importance of early ophthalmologic screening in suspected CED and underscores the utility of ERG in detecting early retinal involvement. The identification of two previously undescribed WDR19 variants contributes to genotype–phenotype correlation in CED and emphasizes the need for ongoing documentation to guide diagnosis, management, and genetic counseling. Full article

Bardet–Biedl syndrome (BBS) is a rare multisystem ciliopathy characterized by early-onset retinal degeneration and other vision-threatening ophthalmologic manifestations. This review synthesizes current knowledge on the ocular phenotype of BBS as well as emerging therapeutic approaches aimed at preserving visual function. Retinal degeneration, particularly early macular involvement and rod–cone dystrophy, remains the hallmark of BBS-related vision loss. Additional ocular manifestations, such as refractive errors, nystagmus, optic nerve abnormalities, and cataracts further contribute to visual morbidity. Experimental therapies—including gene-based interventions and pharmacologic strategies such as nonsense suppression and antioxidant approaches—have shown promise in preclinical models but require further validation. Early ophthalmologic care, including routine visual assessments, refractive correction, and low-vision rehabilitation, remains the standard of management. However, there are currently no effective therapies to halt or reverse retinal degeneration, which underscores the importance of emerging molecular and genetic interventions. Timely recognition and comprehensive ophthalmologic evaluation are essential to mitigate visual decline in BBS. Future efforts should focus on translating these approaches into clinical practice, enhancing early diagnosis, and promoting multidisciplinary collaboration to improve long-term outcomes for patients with BBS. Full article

Background: Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterized by recurrent sinopulmonary infections due to motile cilia defects. The disease is genetically heterogeneous, with abnormalities in structural ciliary proteins. Zinc finger MYND-type containing 10 (ZMYND10) is essential for the assembly of outer dynein arms (ODA), with chaperones like Glucose-regulated protein 78 (GRP78) facilitating protein folding. This study investigates ZMYND10 and Dynein axonemal heavy chain 5 (DNAH5) mutations in individuals with PCD. Methods: Eight individuals aged 14–22 with clinical PCD symptoms and confirmed DNAH5 mutations were included. We analyzed the correlation between DNAH5 abnormalities and preassembly/chaperone proteins using immunofluorescence labeling. Nasal swabs were double-labeled (DNAH5–β-tubulin, β-tubulin–ZMYND10, β-tubulin–GRP78) and examined via fluorescence microscopy. Serum metabolomics and proteomics were also assessed. Results: The corrected total cell fluorescence (CTCF) levels of DNAH5, ZMYND10, and GRP78 were significantly different between PCD individuals and controls. Metabolomic analysis showed reduced valine, leucine, and isoleucine biosynthesis, with increased malate and triacylglycerol biosynthesis, malate-aspartate and glycerol phosphate shuttles, and arginine/proline metabolism, suggesting mitochondrial and ER stress. Conclusions: The altered expression of DNAH5, ZMYND10, and GRP78, along with metabolic shifts, points to a complex link between ciliary dysfunction and cellular stress in PCD. Further studies are needed to clarify the underlying mechanisms. Full article

Autism spectrum disorder (ASD) is a neurodevelopmental impairment that occurs due to mutations related to the formation of the nervous system, combined with the impact of various epigenetic and environmental factors. This necessitates the identification of the genetic variations involved in ASD pathogenesis. We performed whole exome sequencing (WES) in a cohort of 22 Bulgarian male and female individuals showing ASD features alongside segregation analyses of their families. A targeted panel of genes was chosen and analyzed for each case, based on a detailed examination of clinical data. Gene analyses revealed that specific variants concern key neurobiological processes involving neuronal architecture, development, and function. These variants occur in a number of genes, including SHANK3, DLG3, NALCN, and PACS2 which are critical for synaptic signaling imbalance, CEP120 and BBS5 for ciliopathies, SPTAN1 for spectrins structure, SPATA5, TRAK1, and VPS13B for neuronal organelles trafficking and integrity, TAF6, SMARCB1, DDX3X, MECP2, and SETD1A for gene expression, CDK13 for cell cycle control, ALDH5A1, DPYD, FH, and PDHX for mitochondrial function, and PQBP1, HUWE1, and WDR45 for neuron homeostasis. Novel single nucleotide variants in the SPATA5, CEP120, BBS5, SETD1A, TRAK1, VPS13B, and DDX3X genes have been identified and proposed for use in ASD diagnostics. Our data contribute to a better understanding of the complex neurobiological features of autism and are applicable in the diagnosis and development of personalized therapeutic approaches. Full article