Animal Cells and Systems

ESCRT-III: a versatile membrane remodeling machinery and its implications in cellular processes and diseases
Park J, Kim J, Park H, Kim T and Lee S
The endosomal sorting complexes required for transport (ESCRT) machinery is an evolutionarily conserved cytosolic protein complex that plays a crucial role in membrane remodeling and scission events across eukaryotes. Initially discovered for its function in multivesicular body (MVB) formation, the ESCRT complex has since been implicated in a wide range of membrane-associated processes, including endocytosis, exocytosis, cytokinesis, and autophagy. Recent advances have elucidated the ESCRT assembly pathway and highlighted the distinct functions of the various ESCRT complexes and their associated partners. Among the ESCRT complexes, ESCRT-III stands out as a critical player in membrane remodeling, with its subunits assembled into higher-order multimers capable of bending and severing membranes. This review focuses on the ESCRT-III complex, exploring its diverse functions in cellular processes beyond MVB biogenesis. We delve into the molecular mechanisms underlying ESCRT-III-mediated membrane remodeling and highlight its emerging roles in processes such as viral budding, autophagosome closure, and cytokinetic abscission. We also discuss the implications of ESCRT-III dysregulation in neurodegenerative diseases. The versatile membrane remodeling capabilities of ESCRT-III across diverse cellular processes underscore its importance in maintaining proper cellular function. Furthermore, we highlight the promising potential of ESCRT-III as a therapeutic target for neurodegenerative diseases, offering insights into the treatments of the diseases and the technical applications in related research fields.
Reassessing the genetic lineage tracing of lingual and cells
Kim HJ, Seo DW, Shim J, Lee JS, Choi SH, Kim DH, Moon SJ, Jung HS and Jeong YT
Taste buds, the neuroepithelial organs responsible for the detection of gustatory stimuli in the oral cavity, arise from stem/progenitor cells among nearby basal keratinocytes. Using genetic lineage tracing, and were suggested as the specific markers for the stem/progenitor cells of taste buds, but recent evidence implied that taste buds may arise even in the absence of these markers. Thus, we wanted to verify the genetic lineage tracing of lingual - and -expressing cells. Unexpectedly, we found that antibody staining revealed more diverse -expressing cells inside and outside the taste buds of circumvallate papillae than was previously suggested. We also found that, while tamoxifen-induced genetic recombination occurred only in cells expressing the reporter GFP, we did not see any increase in the number of recombined daughter cells induced by consecutive injections of tamoxifen. Similarly, we found that cells expressing , another stem/progenitor cell marker candidate and an analog of , also do not generate recombined clones. In contrast, -expressing cells in fungiform papillae can transform into negative progeny. Together, our data indicate that lingual - and -expressing cells exhibit diversity in their capacity to transform into - and -negative cells, depending on their location. Our results complement previous findings that did not distinguish this diversity.
Licochalcone A attenuates NMDA-induced neurotoxicity
Kim JS, Kim MH, Kim MJ and Kim HJ
This study investigates the effect of Licochalcone A (Lico-A), a flavonoid from licorice roots known for its anti-inflammatory, anti-cancer, and antioxidant properties, on NMDA-induced neurotoxicity in primary cultured rat hippocampal neurons. The study measured cell survival following NMDA and Lico-A exposure, revealing that Lico-A at a 2.5 μg/ml significantly improved cell viability, countering the detrimental effects of NMDA. The study also analyzed synaptic changes by examining both postsynaptic density 95 (PSD95) and synaptophysin-targeted imaging, showing that Lico-A treatment resulted in a significant increase in synaptic puncta, contrasting with the reduction observed under NMDA exposure. Furthermore, levels of phosphorylated mixed lineage kinase domain-like pseudokinase (P-MLKL) and phosphorylated receptor-interacting serine/threonine-protein kinase 3 (P-RIP3), key necroptosis regulators, were measured using Western blotting. The results showed an increase in P-MLKL and P-RIP3 in neurons exposed to NMDA, which was reduced following Lico-A treatment. The response of astrocyte and microglia was also evaluated by immunostaining for glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor molecule 1 (IBA-1) and tumor necrosis factor alpha (TNF-α). These markers exhibited heightened expression in the NMDA group, which was substantially reduced by Lico-A treatment. These findings suggest that Lico-A has neuroprotective effects against NMDA-induced neurotoxicity, potentially contributing to synaptic preservation, inhibition of neuronal necroptosis, and modulation of glial activation. Therefore, Lico-A shows promise as a neuroprotective agent for conditions associated with NMDA-related neurotoxicity.
L. alleviates OVA-induced allergic asthma through NF-κB and MMP-9 pathways
Pak SW, Lee IS, Kim WI, Lee SJ, Kim JC, Shin IS and Kim T
Allergic asthma, a type of chronic airway inflammation, is a global health concern because of its increasing incidence and recurrence rates. L. yields a variety type of teas, which are also used as medicinal plants in East Asia and are known to have antioxidant, anti-inflammatory, and immune-potentiating properties. Here, we examined the constituents of L. extract (CSE) and evaluated the protective effects of CSE on allergic asthma by elucidating the underlying mechanism. To induce allergic asthma, we injected the sensitization solution (mixture of ovalbumin (OVA) and aluminum hydroxide) into mice intraperitoneally on days 0 and 14. Then, the mice were exposed to 1% OVA by a nebulizer on days 21 to 23, while intragastric administration of CSE (30 and 100 mg/kg) was performed each day on days 18 to 23. We detected five compounds in CSE, including (-)-epigallocatechin, caffeine, (-)-epicatechin, (-)-epigallocatechin gallate, and (-)-epicatechin gallate. Treatment with CSE remarkably decreased the airway hyperresponsiveness, OVA-specific immunoglobulin E level, and inflammatory cell and cytokine levels of mice, with a decrease in inflammatory cell infiltration and mucus production in lung tissue. Treatment with CSE also decreased the phosphorylation of nuclear factor-κB (NF-κB) and the expression of matrix-metalloproteinase (MMP)-9 in asthmatic mice. Our results demonstrated that CSE reduced allergic airway inflammation caused by OVA through inhibition of phosphorylated NF-κB and MMP-9 expression.
Cell-autonomous reduction of CYFIP2 changes dendrite length, dendritic protrusion morphology, and inhibitory synapse density in the hippocampal CA1 pyramidal neurons of 17-month-old mice
Kim Y, Ma R, Zhang Y, Kang HR, Kim US and Han K
The cytoplasmic FMR1-interacting protein 2 (CYFIP2) have diverse molecular functions in neurons, including the regulation of actin polymerization, mRNA translation, and mitochondrial morphology and function. Mutations in the gene are associated with early-onset epilepsy and neurodevelopmental disorders, while decreases in its protein levels are linked to Alzheimer's disease (AD). Notably, previous research has revealed AD-like phenotypes, such as dendritic spine loss, in the hippocampal CA1 pyramidal neurons of 12-month-old heterozygous mice but not of age-matched CA1 pyramidal neuron-specific conditional knock-out (cKO) mice. This study aims to investigate whether dendritic spine loss in cKO mice is merely delayed compared to heterozygous mice, and to explore further neuronal phenotypes regulated by CYFIP2 in aged mice. We characterized dendrite and dendritic protrusion morphologies, along with excitatory/inhibitory synapse densities in CA1 pyramidal neurons of 17-month-old cKO mice. Overall dendritic branching was normal, with a reduction in the length of basal, not apical, dendrites in CA1 pyramidal neurons of cKO mice. Furthermore, while dendritic protrusion density remained normal, alterations were observed in the length of mushroom spines and the head volume of stubby spines in basal, not apical, dendrites of cKO mice. Although excitatory synapse density remained unchanged, inhibitory synapse density increased in apical, not basal, dendrites of cKO mice. Consequently, a cell-autonomous reduction of CYFIP2 appears insufficient to induce dendritic spine loss in CA1 pyramidal neurons of aged mice. However, CYFIP2 is required to maintain normal dendritic length, dendritic protrusion morphology, and inhibitory synapse density.
Integrative transcriptomic profiling uncovers immune and functional responses to bisphenol a across multiple tissues in male mice
Park Y, Jang MJ, Ryu DY, Lim B, Pathak RK, Pang MG and Kim JM
Bisphenol A (BPA), an endocrine-disrupting substance commonly found in plastics and receipts, is associated with adverse effects, including endocrine disorders, reduced fertility, and metabolic issues. To gain insights into its effects on biological systems, we observed the adverse effects of BPA in male Institute of Cancer Research (ICR) mice exposed to BPA at the lowest observed adverse effect level for 6 weeks, in comparison with the control groups. We constructed a comprehensive transcriptome profile using 20 different tissues to analyze the changes in the whole-body systems. This involved employing differential gene expression, tissue-specific gene, and gene co-expression network analyses. The study revealed that BPA exposure led to significant differences in the transcriptome in the thymus, suggesting activation of T-cell differentiation and maturation in response to BPA treatment. Furthermore, various tissues exhibited immune response activation, potentially due to the migration of immune cells from the thymus. BPA exposure also caused immune-related functional changes in the colon, liver, and kidney, as well as abnormal signaling responses in the sperm. The transcriptome analysis serves as a valuable resource for understanding the functional impact of BPA, providing profound insights into the effects of BPA exposure and emphasizing the need for further research on potential associated health risks.
CXCL10 promotes melanoma angiogenesis and tumor growth
Kim B, Park YY and Lee JH
Upregulation of CXC motif chemokine 10 (CXCL10) in melanoma patients has been found to be associated with melanoma progression. However, the role of endogenous CXCL10 from the host in melanoma tumor growth remains unclear. In the present study, we found that host-derived endogenous CXCL10 production was dramatically augmented during subcutaneous B16F10 melanoma tumor growth and that host ablation of CXCL10 in mice showed a decrease in both angiogenesis and tumor growth of B16F10 melanoma . Several signaling pathways involved in production of pro-angiogenic factors and tumor growth were activated by CXCL10 in B16F10 melanoma cells. CXCL10 increased expression of pro-angiogenic factors, such as vascular endothelial growth factor (VEGF), platelet-derived growth factor subunit-B (PDGF-B), fibroblast growth factor 2 (FGF2), hepatocyte growth factor (HGF), and angiopoietin 2 (Angpt2), in B16F10 melanoma cells, resulting in enhanced tube formation and proliferation of human umbilical vein endothelial cells . In addition, CXCL10 directly enhanced B16F10 melanoma tumor growth in an three-dimensional cell culture system. Together, our findings reveal that amplified host-derived endogenous CXCL10 is critical for B16F10 melanoma angiogenesis and tumor growth. Therefore, CXCL10 might represent a therapeutic target for melanoma.
Establishment of a stress granule reporter system for evaluating colon toxicity
Cho N, Jung DM, Kim EM and Kim KK
Exposure to toxic molecules from food or oral medications induces toxicity in colon cells that cause various human diseases; however, monitoring systems for colon cell toxicity are not well established. Stress granules are nonmembranous foci that form in cells exposed to cellular stress. When cells sense toxic environments, they acutely and systemically promote stress granule formation, with Ras GTPase-activating protein-binding protein 1 (G3BP1) acting as a core component to protect their mRNA from abnormal degradation. Here, we knocked in green fluorescent protein (GFP)-coding sequences into the C-terminal region of the gene in a human colon cell line through CRISPR-Cas9-mediated homologous recombination and confirmed the formation of stress granules with the G3BP1-GFP protein in these cells under cellular stress exposure. We demonstrated the formation and dissociation of stress granules in G3BP1-GFP expressing colon cells through real-time monitoring using a fluorescence microscope. Furthermore, we validated the toxicity monitoring system in the established colon cell line by observing stress granule formation following exposure to dihydrocapsaicin, bisphenol A, and sorbitol. Taken together, we established a stress granule reporter system in a colon cell line, providing a novel assessment for the real-time monitoring of colon toxicity in response to various chemicals.
Gender-specific alteration of steroid metabolism and its impact on viral replication in a mouse model of hepatitis B virus infection
Park ES, Won J, Ahn SH, Lee AR, Lee D, Moon JY, Choi MH and Kim KH
Hepatitis B virus (HBV) is a sex-specific pathogen that is more severe in males than in females. Sex disparities in HBV infection have been attributed to hormonal differences between males and females. However, whether HBV infection affects the metabolic signatures of steroid hormones and how these influences viral replication remains unclear. In this study, we investigated whether HBV infection alters steroid metabolism and its effects on HBV replication. Serum samples from male and female mice obtained after the hydrodynamic injection of replication-competent HBV plasmids were subjected to quantitative steroid profiling. Serum steroid levels in mice were analyzed using an metabolism assay with the mouse liver S9 fraction. The alteration of steroids by HBV infection was observed only in male mice, particularly with significant changes in androgens, whereas no significant hormonal changes were observed in female mice. Among the altered steroids, dehydroepiandrosterone (DHEA) levels increased the most in male mice after HBV infection. An metabolism assay revealed that androgen levels were significantly reduced in HBV-infected male mice. Furthermore, the genes involved in DHEA biosynthesis were significantly upregulated in HBV-infected male mice. Interestingly, reduced dihydrotestosterone in male mice significantly inhibits viral replication by suppressing HBV promoter activity, suggesting a viral strategy to overcome the antiviral effects of steroid hormones in males. Our data demonstrated that HBV infection can cause sex-specific changes in steroid metabolism.
Effects of maternal nonylphenol exposure on the proliferation of glial cells in the brain of male offspring mice
Lee SH, Shin HS, So YH, Lee DH, Kim JY, Lee EH and Jung EM
Glial cells play a significant role in maintaining brain homeostasis and normal brain development, and their functions can be impaired by exposure to endocrine disruptors. 4-n-Nonylphenol (NP), a representative endocrine disruptor, is widely used in personal care products and industrial materials. NP accumulates in various organs, including the brain, of living organisms and adversely influences brain health. However, studies on the effects of NP on glial cells are limited. This study aims to investigate the effects of NP on glial cells using primary mixed glial cells and offspring mice exposed to NP during gestation and lactation. experiments revealed that NP exposure stimulated the astrocytes and microglia proliferation but not oligodendrocytes. NP exposure activated microglia and reduced myelin protein expression in oligodendrocytes. Moreover, maternal NP exposure increased the numbers of microglia and oligodendrocytes in the cerebral cortex of adult offspring. NP exposure caused anxiety- and depressive-like behaviors in adult mice. Collectively, these findings suggest that maternal NP exposure negatively affects the brain development in adult offspring mice.
Nitrogen-doped carbon quantum dot regulates cell proliferation and differentiation by endoplasmic reticulum stress
Song HH, Choi H, Kim S, Kim HG, An S, Kim S and Jang H
Quantum dots have diverse biomedical applications, from constructing biological infrastructures like medical imaging to advancing pharmaceutical research. However, concerns about human health arise due to the toxic potential of quantum dots based on heavy metals. Therefore, research on quantum dots has predominantly focused on oxidative stress, cell death, and other broader bodily toxicities. This study investigated the toxicity and cellular responses of mouse embryonic stem cells (mESCs) and mouse adult stem cells (mASCs) to nitrogen-doped carbon quantum dots (NCQDs) made of non-metallic materials. Cells were exposed to NCQDs, and we utilized a fluorescent ubiquitination-based cell system to verify whether NCQDs induce cytotoxicity. Furthermore, we validated the differentiation-inducing impact of NCQDs by utilizing embryonic stem cells equipped with the Oct4 enhancer-GFP reporter system. By analyzing gene expression including Crebzf, Chop, and ATF6, we also observed that NCQDs robustly elicited endoplasmic reticulum (ER) stress. We confirmed that NCQDs induced cytotoxicity and abnormal differentiation. Interestingly, we also confirmed that low concentrations of NCQDs stimulated cell proliferation in both mESCs and mASCs. In conclusion, NCQDs modulate cell death, proliferation, and differentiation in a concentration-dependent manner. Indiscriminate biological applications of NCQDs have the potential to cause cancer development by affecting normal cell division or to fail to induce normal differentiation by affecting embryonic development during pregnancy. Therefore, we propose that future biomedical applications of NCQDs necessitate comprehensive and diverse biological studies.
Emerging roles of cytoskeletal transport and scaffold systems in human viral propagation
Lim Y, Cho YB and Seo YJ
Viruses have long been recognized as significant pathogens, contributing to multiple global pandemics throughout human history. Recent examples include the 2009 influenza pandemic and the COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019. Despite ongoing experimental and clinical efforts, the development of effective antiviral treatments and vaccines remains challenging due to the high mutation rates of many human pathogenic viruses including influenza virus and SARS-CoV-2. As an alternative approach, antiviral strategies targeting host factors shared by multiple viruses could provide a more universally applicable solution. Emerging evidence suggests that viruses exploit the host cytoskeletal network to facilitate efficient viral replication and propagation. Therefore, a comprehensive understanding of the interactions between viral components and the cytoskeletal machinery may offer valuable insights for the development of broad-spectrum antiviral therapeutics. This review compiles and discusses current knowledge on the interactions between viruses and cytoskeletal elements, including kinesin, dynein, myosin, and vimentin, and explores their potential as therapeutic targets. The potential for these cytoskeletal components to serve as targets for new antiviral interventions is discussed in the context of diverse human viruses, including influenza virus, SARS-CoV-2, herpes simplex virus, human papillomavirus, and human immunodeficiency virus.
Ank-mediated pyrophosphate regulates shear stress-induced small extracellular vesicle production in 3D-cultured osteocytes
Lee SJ, Jung DK, Im S, You C, Kim JE, Bae JS, Kim MS, Yea K and Park EK
Osteocytes are located in the lacunae of fluid-filled bone and communicate with neighboring or distant cells by secreting small extracellular vesicles (sEVs) and growth factors as well as via dendrite-dendrite direct connections. However, the mechanism regulating sEV production in osteocytes is yet to be elucidated. In this study, we investigated sEV production and its underlying mechanism in osteocytes cultured on a three dimensional (3D) scaffold. We employed a perfusion system to apply shear stress stimulation to MLO-Y4 cells cultured on a 3D biphasic calcium phosphate (BCP) scaffold and analyzed sEV production and gene expression using RNA sequencing. We found that the expression of genes associated with sEV biogenesis and the secretory pathway were enhanced by fluid shear stress in MLO-Y4 cells cultured on a 3D BCP scaffold. In particular, fluid shear stress induced the expression of Ank, a pyrophosphate transporter, in 3D-cultured MLO-Y4 cells. The role of Ank in sEV production was further examined. Probenecid, an Ank inhibitor, significantly suppressed shear stress-induced sEV production, whereas Ank cDNA overexpression stimulated it. The inhibition of shear stress-induced sEV production by probenecid was recovered by the exogenous addition of pyrophosphate to MLO-Y4 cells. These findings suggest that shear stress-mediated sEV production in 3D-cultured osteocytes is regulated by extracellular pyrophosphate transported by Ank.
Anti-obesity and immunomodulatory effects of oil and fermented extract dried from larvae on aged obese mice
Mun SK, Jang CJ, Jo S, Park SH, Sim HB, Ramos SC, Kim H, Choi YJ, Park DH, Park KW, Jeong BG, Kim DH, Kang KY and Kim JJ
Preventing disease and maintaining the health of the elderly are crucial goals for an aging population, with obesity and immune function restoration being of paramount importance. Obesity, particularly visceral obesity characterized by excessive fat accumulation around the abdominal organs, is linked to chronic conditions such as diabetes, hypertension, cardiovascular diseases, and immune dysfunction. Globally, obesity is considered a disease, prompting significant research interest in its treatment. Therefore, it is essential to explore potential therapeutic and preventive strategies to address obesity and the decline in immune function brought about by aging. larvae (TML), commonly known as 'mealworms,' are rich in unsaturated fatty acids, including oleic and linoleic acids, and essential amino acids, such as isoleucine and tyrosine. In this study, we aimed to investigate the effects of the consumption of TML oil and mealworm fermented extract (MWF-1) on obesity and immunological changes in aged obese mice. Our data showed reduced body fat in 23-week-old C57BL/6 mice fed processed TML products for 6 weeks. Additionally, the characteristically high levels of serum triglycerides decreased by treating with TML oil. The immune responsiveness results confirmed an increase in B cells by treating with MWF-1, while cytokine levels (interferon-gamma, tumor necrosis factor-alpha, interleukin-2, and -6) were restored to levels similar to young mice. These results suggest that TML oil and MWF-1 are promising dietary supplements for addressing obesity and restoring immune function.
Low-temperature pulverization-specific extract accelerates wound healing and attenuates inflammation in a mouse burn model
Shin E, Kim HT, Lee H, Kim B, Park J, Park S, Yum S, Kim SK, Lee JM and Youn B
Burn injuries, affecting local skin disruption as well as inducing systemic inflammatory responses, are presented as a global public health problem. To enhance the effects of burn wound healing, treatment must simultaneously regulate both re-epithelialization and hyperinflammation. Extracts of () have shown a potential to enhance skin wound healing through antioxidative properties, immune enhancement, and modulation of inflammatory responses. However, despite its promising application for burn wound healing, specific investigation into -derived compounds for enhancing wound healing has not yet been conducted. In this research, we investigated the burn wound-healing effect of the low-temperature pulverization-specific extract (LPSHE), which could not be detected using the room-temperature grinding method. In a mouse burn model with third-degree burn injuries, LPSHE accelerated re-epithelialization by promoting the increase in F-actin formation and reduced burn-induced ROS levels. Additionally, LPSHE significantly regulated hyperinflammation by reducing pro-inflammatory cytokines. Further investigation into molecular mechanisms using HaCaT keratinocytes also demonstrated beneficial effects on burn wound healing. Taken together, our findings suggested that LPSHE is a promising therapeutic candidate for enhancing burn wound healing. Furthermore, this research underscored the importance of low-temperature pulverization in discovering novel natural compounds from marine organisms.
Piperlongumine regulates genes involved in the skin barrier in epidermal keratinocyte HaCaT cells
Lee KH, Kang DG, Kim DW, Do HK, Kim DY and Kim W
Given that the skin is the largest tissue in the human body, performing external barrier functions with innate and adaptive immunity and undergoing substantial changes during aging, it is under investigation as a major target of various bioactive molecules. In the present study, we examined the biological activity of the senolytic piperlongumine by analyzing alterations in mRNA expression of notable skin genes using transformed aneuploid immortal epidermal keratinocytes, HaCaT cells. We observed that piperlongumine increased the mRNA expression of genes playing critical roles in skin barrier function. In addition, piperlongumine increased expression enzymes involved in the synthesis of ceramide, a major component of intercellular lipids. Furthermore, we measured the protein levels of various cytokines secreted by epidermal keratinocytes and found changes in the release of GRO-αβγ, CCL5, and MCP1. Additionally, we observed that piperlongumine treatment modulated the expression of keratinocyte-specific aging markers and influenced telomerase activity. Based on these findings, piperlongumine could regulate the physiological activity of epidermal keratinocytes to induce beneficial effects in human skin by regulating important skin-related genes.
ECM stiffness regulates calcium influx into mitochondria via tubulin and VDAC1 activity
Kim M, Han K, Choi G, Ahn S, Suh JS and Kim TJ
Calcium ions (Ca) play pivotal roles in regulating numerous cellular functions, including metabolism and growth, in normal and cancerous cells. Consequently, Ca signaling is a vital determinant of cell fate and influences both cell survival and death. These intracellular signals are susceptible to modulation by various factors, including changes in the extracellular environment, which leads to mechanical alterations. However, the effect of extracellular matrix (ECM) stiffness variations on intracellular Ca signaling remains underexplored. In this study, we aimed to elucidate the mechanisms of Ca regulation through the mitochondria, which are crucial to Ca homeostasis. We investigated how Ca regulatory mechanisms adapt to different levels of ECM stiffness by simultaneously imaging the mitochondria and endoplasmic reticulum (ER) in live cells using genetically encoded biosensors. Our findings revealed that the uptake of mitochondrial Ca through Voltage-Dependent Anion Channel 1 (VDAC1), facilitated by intracellular tubulin, is influenced by ECM stiffness. Unraveling these Ca regulatory mechanisms under various conditions offers a novel perspective for advancing biomedical studies involving Ca signaling.
Generation of mouse and rat xenogeneic ovaries for production of mouse oocyte
Jang SW, Kim YR, Han JH, Jang H and Choi HW
The system forming ovarian follicles is developed to investigate folliculogenesis in a confined environment to obtain functional oocytes. Several studies have reported the successful generation of fully functional oocytes using mouse-induced pluripotent stem cells (iPSCs) and mouse female germline stem cells (fGSCs) as sources of stem cells for gametogenesis models. In addition, human oogonia have been generated through heterologous co-culture of differentiated human primordial germ cell-like cells (hPGCLCs) with mouse germline somatic cells, although oocyte formation remains challenging. Thus, studies on ovarian formation in other species are utilized as an introductory approach for mammalian gametogenesis by understanding the differences in culture systems between species and underlying mechanisms. In this study, we optimized the method of the entire oogenesis process from rat embryonic gonads. We identified well-maturated MII oocytes from rat gonads using our constructed method. Moreover, we generated the first successful reconstitution of xenogeneic follicles from mouse primordial germ cells (PGCs) and rat somatic cells. We also established an appropriate culture medium and incubation period for xenogeneic follicles. This method will be helpful in studies of xenogeneic follicular development and oocyte generation.
Lamin A/C facilitates DNA damage response by modulating ATM signaling and homologous recombination pathways
Kim SJ, Park SH, Myung K and Lee KY
Lamin A/C, a core component of the nuclear lamina, forms a mesh-like structure beneath the inner nuclear membrane. While its structural role is well-studied, its involvement in DNA metabolism remains unclear. We conducted sequential protein fractionation to determine the subcellular localization of early DNA damage response (DDR) proteins. Our findings indicate that most DDR proteins, including ATM and the MRE11-RAD50-NBS1 (MRN) complex, are present in the nuclease - and high salt-resistant pellet fraction. Notably, ATM and MRN remain stably associated with these structures throughout the cell cycle, independent of ionizing radiation (IR)-induced DNA damage. Although Lamin A/C interacts with ATM and MRN, its depletion does not disrupt their association with nuclease-resistant structures. However, it impairs the IR-enhanced association of ATM with the nuclear matrix and ATM-mediated DDR signaling, as well as the interaction between ATM and MRN. This disruption impedes the recruitment of MRE11 to damaged DNA and the association of damaged DNA with the nuclear matrix. Additionally, Lamin A/C depletion results in reduced protein levels of CtIP and RAD51, which is mediated by transcriptional regulation. This, in turn, impairs the efficiency of homologous recombination (HR). Our findings indicate that Lamin A/C plays a pivotal role in DNA damage repair (DDR) by orchestrating ATM-mediated signaling, maintaining HR protein levels, and ensuring efficient DNA repair processes.
HSPA5 and FGFR1 genes in the mesenchymal subtype of glioblastoma can improve a treatment efficacy
Lee JY, Park J and Hong D
Tyrosine kinase inhibitors (TKIs) have emerged as a potential treatment strategy for glioblastoma multiforme (GBM). However, their efficacy is limited by various drug resistance mechanisms. To devise more effective treatments for GBM, genetic characteristics must be considered in addition to pre-existing treatments. We performed an integrative analysis with heterogeneous GBM datasets of genomic, transcriptomic, and proteomic data from DepMap, TCGA and CPTAC. We found that poor prognosis was induced by co-upregulation of heat shock protein family A member 5 () and fibroblast growth factor receptor 1 (). Co-up regulation of these two genes could regulate the PI3K/AKT pathway. GBM cell lines with co-upregulation of these two genes showed higher drug sensitivity to PI3K inhibitors. In the mesenchymal subtype, the co-upregulation of FGFR1 and HSPA5 resulted in the most malignant subtype of GBM. Furthermore, we found this newly discovered subtype was correlated with homologous recombination deficiency (HRD) In conclusion, we discovered novel druggable candidates within the group exhibiting co-upregulation of these two genes in GBM, suggest potential strategies for combination therapy.
AP001885.4 promotes the proliferation of esophageal squamous cell carcinoma cells by histone lactylation- and NF-κB (p65)-dependent transcription activation and METTL3-mediated mRNA stability of c-myc
Fu C, Jiang W, Wang C, Song SJ, Tao H, Zhang XG, Li WT, Jin X, Yu BB, Hao JJ, Sun WJ, Bai J and Shi ZZ
Esophageal squamous cell carcinoma (ESCC) is an aggressive malignant neoplasm, and up to now, the role of long non-coding RNA (lncRNA) AP001885.4 in cancer, including ESCC, is absolutely unclear. The GEPIA database was applied to identify differentially expressed and prognosis-associated genes in esophageal cancer (ESCA). CCK-8, colony formation, Western blot, and qRT-PCR methods were harnessed to investigate the role and mechanism of AP001885.4 in esophageal carcinogenesis. By analyzing TCGA data in the GEPIA database, two lncRNAs were selected. AP001885.4 was overexpressed and positively associated with the unfavorable outcome of ESCC patients, and LINC001786 was under-expressed and negatively linked with the poor prognosis. Knockdown of AP001885.4 suppressed the proliferation and colony formation of ESCC cells. Importantly, the silence of AP001885.4 downregulated c-myc. Mechanically, the knockdown of AP001885.4 reduced METTL3 expression and m6A modification in c-myc mRNA, and METTL3 positively regulated c-myc. Furthermore, the knockdown of AP001885.4 diminished histone lactylation and NF-κB (p65) expression, and the protein lactylation inhibitors (2-DG, 2-deoxy-D-glucose and oxamate) and the NF-κB inhibitor (JSH-23) also lessened c-myc expression. Consequently, our findings suggested that AP001885.4 promoted the proliferation of esophageal squamous cell carcinoma cells by histone lactylation- and NF-κB (p65)-dependent transcription activation and METTL3-mediated mRNA stability of c-myc.