Search Results (199)

The Ataxin-2-like (ATXN2L) protein is required to survive embryonic development, as documented in mice with the constitutive absence of the ATXN2L Lsm, LsmAD, and PAM2 domains due to knock-out (KO) of exons 5–8 with a frameshift. Its less abundant paralog, Ataxin-2 (ATXN2), has an extended N-terminus, where a polyglutamine domain is prone to expansions, mediating vulnerability to the polygenic adult motor neuron disease ALS (Amyotrophic Lateral Sclerosis) or causing the monogenic neurodegenerative processes of Spinocerebellar Ataxia Type 2 (SCA2), depending on larger mutation sizes. Here, we elucidated the physiological function of ATXN2L by deleting the LsmAD and PAM2 motifs via loxP-mediated KO of exons 10–17 with a frameshift. Crossing heterozygous floxed mice with constitutive Cre-deleter animals confirmed embryonic lethality among offspring. Crossing with CamK2a-CreERT2 mice and injecting tamoxifen for conditional deletion achieved chimeric ATXN2L absence in CamK2a-positive frontal cortex neurons and reduced spontaneous horizontal movement. Global proteome profiling of frontal cortex homogenate showed ATXN2L levels decreased to 75% and dysregulations enriched in the alternative splicing pathway. Nuclear proteins with Sm domains are critical to performing splicing; therefore, our data suggest that the Like-Sm (Lsm, LsmAD) domains in ATXN2L serve a role in splice regulation, despite their perinuclear location. Full article

Transformer 2 beta (TRA2β) is a critical RNA-binding protein that regulates gene alternative splicing and is involved in cell cycle progression, neuronal differentiation, and cytoskeletal organization. It plays an essential role in embryonic development, particularly neurogenesis, where its deletion leads to severe cortical malformations and perinatal lethality. Dysregulation of TRA2β has been implicated in a range of diseases, including neurological, oncological, and immune-related disorders. Given its broad influence, TRA2β is a compelling candidate for targeted therapies and diagnostic biomarkers. This review highlights recent advances in our understanding of TRA2β regulation and its role in modulating alternative splicing across diverse cell types. It emphasizes TRA2β’s dual function as both a developmental regulator and a disease modulator and explores emerging insights into its therapeutic potential and future research directions. A deeper understanding of the cell-specific regulation of TRA2β may accelerate the development of innovative therapeutic strategies targeting this versatile protein. Full article

SLC35A2-CDG is a congenital disorder of glycosylation caused by mutations in the SLC35A2 gene encoding a Golgi-localized UDP-galactose transporter. This transporter plays an essential role in glycan synthesis by transporting UDP-galactose from the cytoplasm into the Golgi lumen. Its dysfunction leads to impaired galactose-containing glycans and various neurological symptoms, although the underlying mechanisms remain largely unknown. We identified a novel SLC35A2-CDG patient carrying a pathogenic variant (c.617_620del, p.(Gln206ArgfsTer45)) who exhibited neurological abnormalities including bilateral ventriculomegaly. To investigate the disease mechanism, we established the first Drosophila model of SLC35A2-CDG. Knockout of Ugalt, the fly ortholog of SLC35A2, resulted in embryonic lethality, indicating its essential role. Knockdown of Ugalt reduced mucin-type O-glycans on muscles and neuromuscular junctions (NMJs), without affecting N-glycans. Ugalt knockdown larvae exhibited mislocalized NMJ boutons accompanied by a deficiency in basement membrane components on muscles. This phenotype resembles that of mutants of dC1GalT1 and dGlcAT-P, both involved in mucin-type O-glycosylation. Genetic interaction between Ugalt and dC1GalT1 was confirmed through double knockdown and double heterozygous analyses. Given that Drosophila NMJs are widely used as a model for mammalian central synapses, our findings suggest that Ugalt regulates NMJ architecture via mucin-type O-glycosylation and provide insights into the molecular basis of neurological abnormalities in SLC35A2-CDG. Full article

Background/Objectives: Fish eggs activated with UV-irradiated spermatozoa and exposed to the High Hydrostatic Pressure (HHP) shock to inhibit first cell cleavage develop as gynogenetic Doubled Haploids (DHs) that are fully homozygous individuals. Due to the expression of the recessive genes and side effects of the gamete treatment, survival of fish DHs is rather low, and most of the mitotic gynogenotes die before hatching. Nevertheless, as maternal gene products provided during oogenesis control the initial steps of embryonic development in fish, a maternal effect on the survival of gynogenotes needs to be also considered to affect efficiency of gynogenesis. Thus, the objective of this research was to apply an RNA-seq approach to discriminate transcriptional differences between rainbow trout (Oncorhynchus mykiss) eggs with varied abilities to develop after gynogenetic activation. Methods: Gynogenetic development of rainbow trout was induced in eggs originated from eight females. Maternal RNA was isolated and sequenced using RNA-Seq approach. Survival rates of gynogenotes and transcriptome profiles of eggs from different females were compared. Results: RNA-seq analysis revealed substantial transcriptional differences between eggs originated from different females, and a significant correlation between the ability of the eggs for gynogenesis and their transcriptomic profiles was observed. Genes whose expression was altered in eggs with the increased survival of DHs were mostly associated (GO BP) with the following biological processes: development, cell differentiation, cell migration and protein transport. Some of the genes are involved in the oocyte maturation (RASL11b), apoptosis (CASPASE 6, PGAM5) and early embryogenesis, including maternal to zygotic transition (GATA2). Conclusions: Inter-individual variation of the transcription of maternal genes correlated with the competence of eggs for gynogenesis suggest that at least part of the mortality of the rainbow trout DHs appear before activation of zygotic genome and expression of the lethal recessive traits. Full article

Casein Kinase II (CK2) is a ubiquitously present serine/threonine kinase essential for mammalian development. CK2 holoenzyme is a tetramer with two highly related catalytic subunits (α or α’) and two regulatory ß subunits. Global deletion of the α or β subunit in mice is embryonically lethal. We and others have shown that CK2 is overexpressed in leukemia cells and plays an important role in cell cycle, survival, and resistance to the apoptosis of leukemia stem cells (LSCs). To study the role of CK2α in adult mouse hematopoiesis, we generated hematopoietic cell-specific CK2α-conditional knockout mice (Vav-iCreCK2 ^f/f). Here we report the generation and validation of a novel mouse model that lacks CK2α in the hematopoietic compartment. Vav-iCreCK2α ^f/f mice were viable without dysmorphic features and showed a mild phenotype under baseline conditions. In Vav-iCreCK2α ^f/f mice, the blood count showed a significant decrease in total red blood cells and platelets. The spleen was enlarged in Vav-iCreCK2α ^f/f mice with evidence of extramedullary hematopoiesis. HSC and early progenitor cell compartments showed expansion in CK2α-null bone marrow, suggesting that the absence of CK2α impaired their proliferation and differentiation. Given the established roles of CK2 in cell cycle regulation and the findings reported here, further functional studies are warranted to investigate the role of CK2α in HSC self-renewal and differentiation. This mouse model serves as a valuable tool for understanding the role of CK2α in normal and malignant hematopoiesis. Full article

Background: Ovarian cancer remains the most lethal gynecological cancer, primarily due to its asymptomatic nature in early stages and consequent late diagnosis. Early detection improves survival, but current biomarkers lack sensitivity and specificity. Cell-free DNA (cfDNA) released from tumor cells captures tumor-associated epigenetic alterations and represents a promising source for minimally invasive biomarkers. Among these, aberrant DNA methylation occurs early in tumorigenesis and may reflect underlying disease biology. This study aimed to investigate genome-wide cfDNA methylation profiles in patients with ovarian cancer, benign ovarian conditions, and healthy controls to identify cancer-associated methylation patterns that may inform future biomarker development. Results: We performed genome-wide cfDNA methylation profiling using cell-free methylated DNA immunoprecipitation sequencing (cfMeDIP-seq) on plasma samples from 40 patients with high-grade serous ovarian carcinoma, 38 patients with benign ovarian conditions, and 38 healthy postmenopausal women. A total of 536 differentially methylated regions (DMRs) were identified between ovarian cancer and controls (n = 76), with 97% showing hypermethylation in ovarian cancer. DMRs were enriched in CpG islands and gene bodies and depleted in repetitive elements, consistent with known cancer-associated methylation patterns. Fifteen genes showed robust hypermethylation across analyses. These genes exhibited methylation across intronic, exonic, and upstream regulatory regions. Separate comparisons of ovarian cancer to each control group (benign and healthy) supported the reproducibility of these findings. Gene Ontology enrichment analysis revealed enrichment in gland development, embryonic morphogenesis, and endocrine regulation, suggesting biological relevance to ovarian tumorigenesis. Conclusions: This study identifies consistent cfDNA hypermethylation patterns in ovarian cancer, affecting genes involved in developmental regulation and hormone-related processes. Our findings underscore the potential of cfMeDIP-seq for detecting tumor-specific methylation signatures in plasma and highlight these 15 hypermethylated genes as biologically relevant targets for future studies on cfDNA methylation in ovarian cancer. Full article

The conversion of carbohydrates into fatty acids is central for energy storage and the development and functioning of organs. Our previous study revealed that Hacd2 deficiency alleviates the fatty liver and diabetes induced by HFD. This study aimed to explore the roles of Hacd2 in organ development and metabolic homeostasis under an LFHCD, which still need to be more deeply explored. We found that the germline deletion of Hacd2 impairs long-chain fatty acid synthesis, which caused embryonic abnormalities after 7.5 days and led to embryonic lethality, as confirmed via photograph and hematoxylin-eosin staining. We next constructed Hacd2LKO mice and found that Hacd2LKO mice were largely normal when fed a chow diet, except for reduced inguinal white adipose tissue formation and glucose metabolism. Meanwhile, under an LFHCD, Hacd2 deletion markedly controlled body weight and white adipose tissue formation, leading to lower cholesterol and triglycerides in serum; however, it unexpectedly resulted in enlarged liver volume, hepatocyte swelling and nuclear abnormalities, and infiltration of inflammatory cells, including macrophages, neutrophils and dendritic cells. Furthermore, inhibition of Hacd2 also reduced triglyceride levels and the expression of related lipogenic genes during adipocyte differentiation, as confirmed via RNA interference analysis. These findings highlight the critical roles of Hacd2 in embryonic development and metabolic diseases, revealing its protective function in maintaining liver homeostasis under an LFHCD. Therefore, targeted interventions involving Hacd2 for metabolic diseases must take into account dietary changes and the functioning of the liver. Full article

The presence of pesticides in surface waters has been widely reported worldwide and represents a significant problem that raises concerns on local, regional, national, and international scales. Among these, metolachlor is one of the most widely used herbicides to control annual grasses and broadleaf weeds in various crops. Despite the existing research, data on the effects of metolachlor on the nervous system of fishes, remain limited. The present study aims to investigate the impact of metolachlor during embryonic development on the formation of the nervous system and the subsequent inflammatory response in zebrafish (Danio rerio), focusing specifically on larvae at 24 h post-fertilization (hpf). To achieve this, transgenic zebrafish lines marking neuronal populations Tg(Hu:GFP), glial cells Tg(gfap:GFP), and circulating macrophages Tg(mpeg:GFP) were employed. Following exposure to sub-lethal doses of metolachlor, we observed a significant decrease in GPF-positive cells marking the neuronal population, accompanied by an increase in apoptotic cells within the brain region. Additionally, treated embryos exhibited a marked neuroinflammatory response, characterized by astrogliosis and the specific accumulation of microglia/macrophage-positive cells in the head region. In situ hybridization and real-time PCR analyses revealed a significant downregulation of the neurogenin-1 (ngn1) transcript and a noticeable upregulation of the pro-inflammatory cytokine interleukin-1 beta (il1b). Our findings contribute to the growing body of evidence suggesting that metolachlor, even at early developmental stages, can have detrimental effects on both the formation of the nervous system and the regulation of immune responses. Full article

During the 2009 H1N1 pandemic (pdm09), the poor replication of PR8-derived vaccine strains in embryonated chicken eggs (ECEs) delayed vaccine production, necessitating costly adjuvants. To improve egg-based yield, we generated PB2-substituted H1N1 strains via reverse genetics, replacing PR8 PB2 with a PB2 lacking mammalian-adaptive mutations (dtxPB2), cognate pdm09 PB2 (19PB2), or avian PB2. All PB2-substituted strains achieved over tenfold higher titers than the conventional PR8 PB2-containing strain (rGD19), with rGD19/dtxPB2 and rGD19/19PB2 exhibiting significantly higher titers and reduced murine virulence. Among these, rGD19/19PB2 produced the highest hemagglutinin (HA) yield and, when administered intranasally as a binary ethyleneimine (BEI)-inactivated whole-virion vaccine, elicited a significantly stronger broncho-alveolar IgA response than rGD19. Both rGD19 and rGD19/19PB2 provided comparable protection against a homologous H1N1 challenge, yet only rGD19/19PB2 conferred full survival protection after a lethal heterologous H3N2 challenge. These findings show that incorporation of cognate PB2 enhances H1N1 replication in ECEs and antigen yield, reduces murine virulence, and confers robust homo- and heterosubtypic protection via intranasal immunization, underscoring the promise of PB2-modified H1N1 strains as inactivated mucosal whole-virion vaccines for future vaccine development. Full article

STRAP (serine-threonine kinase receptor-associated protein), a WD domain-containing 38.5 kDa protein, was first identified in TGF-ß signaling and participates in scaffold formation in numerous cellular multiprotein complexes. It is involved in the regulation of several oncogenic biological processes, including cell proliferation, apoptosis, migration/invasion, tumor initiation and progression, and metastasis. STRAP upregulation in epithelial tumors regulates several signaling pathways, such as TGF-ß, MEK/ERK, Wnt/β-Catenin, Notch, PI3K, NF-κB, and ASK-1 in human cancers, including colon, breast, lung, osteosarcoma, and neuroblastoma. The upregulation of STRAP expression is correlated with worse survival in colorectal cancer following post-adjuvant therapy. Strap knockout sensitizes colon tumors to chemotherapy, delays APC-induced tumor progression, and reduces cancer cell stemness. The loss of Strap disrupts lineage differentiation, delays neural tube closure, and alters exon skipping, resulting in early embryonic lethality in mice. Collectively, the purpose of this review is to update and describe the diversity of targets functionally interacting with STRAP and to rationalize the involvement of STRAP in a variety of signaling pathways and biological processes. Therefore, these in vitro and in vivo studies provide a proof of concept that lowering STRAP expression in solid tumors decreases tumorigenicity and metastasis, and targeting STRAP provides strong translational potential to develop pre-therapeutic leads. Full article

ESS2 (ess-2 splicing factor homolog, also known as DGCR14 or DGS-I) is a member of the deletion gene cluster in the 22q11.2 deletion syndrome (22q11.2DS, also known as DiGeorge syndrome or CATCH 22 syndrome). The ESS2 gene is not part of a gene family, and the coded protein has a coiled-coil structure (Es domain), which is conserved from yeast to humans. Recent studies have shown that ESS2 is involved in splicing C and C* complex, but other interactants, such as transcription factors and U1 snRNP, are also reported. Although the molecular mechanism is still under investigation, ESS2 plays a pivotal role in cell differentiation and proliferation. ESS2 knockout mice show embryonic lethal in the early stage, and recent studies show the association of ESS2 with cancer, autoimmune disease, and neurodevelopmental disorders. ESS2 can regulate mRNA splicing and transcriptional activity through interactions with other proteins, and ESS2-dependent gene expression regulation seems to be cell type-selective. In this review, we summarized the cloning history and functions of ESS2, including recent findings. Full article

Background/Objectives: The inhibitor of growth family member 3 (ING3) acts as an epigenetic reader through physical interactions with histone-modifying enzymes and subsequent chromatin remodelling processes. It is involved in various cellular functions, such as cell cycle control, cell growth, and apoptosis. Although ING3 was assigned tumour suppressor candidate status in some types of cancers, including prostate cancer, some studies suggest it acts to promote growth. To address these contradictory reports regarding its role in the initiation and progression of prostate cancer, we specifically addressed the question of whether ablation of ING3 in the mouse prostate is sufficient to initiate malignant transformation of the prostate and support its (candidate) tumour suppressor status. Methods: To generate the prostate-specific Ing3 knockout mouse, paternal inheritance of the PB-Cre4 transgene was used, while for the generation of a global knockout control, a female mouse harbouring the PB-Cre4 transgene was utilized. To determine the recombination efficiency of the Cre-LoxP system in the prostate at the Ing3 locus, a duplex probe-based digital PCR assay capable of counting undisrupted Ing3 copies was designed. The impact of DNA recombination on the protein level was investigated by immunohistochemical staining of prostate tissue samples. Results: In the prostate-specific knockout, digital PCR analysis revealed mosaic gene deletion. We found recombination efficiencies in the anterior, dorsolateral, and ventral prostate lobes ranging from approximately 15 to 30%. ING3 staining in the prostate was faint with no detectable differences in signal intensity between the knockout specimen and wild-type controls. This low ING3 expression in the prostate is consistent with observations of X-gal staining of an Ing3-LacZ reporter allele. Immunohistochemistry showed increased expression of DNA-damage-associated markers γH2AX and 53BP1. However, no gross anatomical abnormalities or prostate intraepithelial neoplasia (PIN) lesions in the prostate of tissue-specific knockout animals compared to wild-type controls were observed. Conclusions: Altogether, our data provide evidence that disruption of ING3 expression in prostate cells does not lead to malignant transformation and challenges the idea that ING3 acts primarily in a tumour-suppressive manner. Furthermore, this work supports the crucial role of ING3 in maintaining genomic stability, and we confirmed the embryonic lethal phenotype of homozygous Ing3 null mice that is rescued by ectopic expression of ING3. Full article

Filamin C (FLNC) is a structural protein of muscle fibers. Mutations in the FLNC gene are known to cause myopathies and cardiomyopathies in humans. Here we report the generation by a CRISPR/Cas9 editing system injected into zygote pronuclei of two mouse strains carrying filamin C mutations—one of them (AGA) has a deletion of three nucleotides at position c.7418_7420, causing E>>D substitution and N deletion at positions 2472 and 2473, respectively. The other strain carries a deletion of GA nucleotides at position c.7419_7420, leading to a frameshift and a premature stop codon. Homozygous animals (Flnc^AGA/AGA and Flnc^GA/GA) were embryonically lethal. We determined that Flnc^GA/GA embryos died prior to the E12.5 stage and illustrated delayed development after the E9.5 stage. We performed histological analysis of heart tissue and skeletal muscles of heterozygous strains carrying mutations in different combinations (Flnc^GA/wt, Flnc^AGA/wt, and Flnc^GA/AGA). By performing physiological tests (grip strength and endurance tests), we have shown that heterozygous animals of both strains (Flnc^GA/wt, Flnc^AGA/wt) are functionally indistinguishable from wild-type animals. Interestingly, compound heterozygous mice (Flnc^GA/AGA) are viable, develop normally, reach puberty and it was verified by ECG and Eco-CG that their cardiac muscle is functionally normal. Intriguingly, Flnc^GA/AGA mice demonstrated better results in the grip strength physiological test in comparison to WT animals. We also propose a structural model that explains the complementary interaction of two mutant variants of filamin C. Full article

ADAM10 is a multi-functional proteinase that can cleave approximately 100 different substrates. Previously, it was demonstrated that ADAM10 is expressed by ameloblasts, which are required for enamel formation. The goal of this study was to determine if ADAM10 is necessary for enamel development. Deletion of Adam10 in mice is embryonically lethal and deletion of Adam10 from epithelia is perinatally lethal. We therefore deleted Adam10 from ameloblasts. Ameloblast-specific expression of the Tg(Amelx-iCre)872pap construct was confirmed. These mice were crossed with Adam10 floxed mice to generate Amelx-iCre; Adam10^fl/fl mice (Adam10 cKO). The Adam10 cKO mice had discolored teeth with softer than normal enamel. Notably, the Adam10 cKO enamel density and volume were significantly reduced in both incisors and molars. Moreover, the incisor enamel rod pattern became progressively more disorganized, moving from the DEJ to the outer enamel surface, and this disorganized rod structure created gaps and S-shaped rods. ADAM10 cleaves proteins essential for cell signaling and for enamel formation such as RELT and COL17A1. ADAM10 also cleaves cell-cell contacts such as E- and N-cadherins that may support ameloblast movement necessary for normal rod patterns. This study shows, for the first time, that ADAM10 expressed by ameloblasts is essential for proper enamel formation. Full article