The incre asing interest in RNA modifications has signifcantly advanced epigenomic and epitranscriptomic technologies.This study focuses on the immuno oncological impact of ALYREF in human cancer through a pan-cancer ...The incre asing interest in RNA modifications has signifcantly advanced epigenomic and epitranscriptomic technologies.This study focuses on the immuno oncological impact of ALYREF in human cancer through a pan-cancer analysis,enhancing understanding of this gene's role in cancer.We observed differential ALYREF expression between tumor and normal samples,correl ating strongly with prognosis in various cancers,particularly kidney renal papillary cell carcinoma(KIRP)and liver hepatocellular carcinoma(LIHC).ALYREF showed a negative correlation with most tumor-infitrating cells in lung squamous cell carcinoma(LUSC)and lymphoid neoplasm difuse large B-cell lymphoma(DLBC),while positive correlations were noted in IIHC,kidney chromophobe(KICH),mesothelioma(MESO),KIRP,pheochromocytoma and paraganglioma(PARD),and glioma(GBMLGG).Aditionally,ALYREF expression was closely associated with tumor heterogeneity,stemness indices,and a high mutation rate in TP53 across these cancers.In conclusion,ALYREF may serve as an oncogenic biomarker in numerous cancers,meriting further research attention.展开更多
5-Methylcytosine (m^5C) is a well-characterized DNA modification, and is also predominantly reported in abundant non-coding RNAs in both prokaryotes and eukaryotes. However, the distribution and biological functions...5-Methylcytosine (m^5C) is a well-characterized DNA modification, and is also predominantly reported in abundant non-coding RNAs in both prokaryotes and eukaryotes. However, the distribution and biological functions of m^5C in plant mRNAs remain largely unknown. Here, we report transcriptome-wide profiling of RNA m^5C in Arabidopsis thaliana by applying m^5C RNA immunoprecipitation followed by a deep- sequencing approach (m^5C-RIP-seq). LC-MS/MS and dot blot analyses reveal a dynamic pattern of m^5C mRNA modification in various tissues and at different developmental stages, m^5C-RIP-seq analysis identified 6045 m^5C peaks in 4465 expressed genes in young seedlings. We found that m^5C is enriched in coding sequences with two peaks located immediately after start codons and before stop codons, and is associated with mRNAs with low translation activity. We further demonstrated that an RNA (cytosine-5)-methyl- transferase, tRNA-specific methyltransferase 4B (TRM4B), exhibits m^5C RNA methyltransferase activity. Mutations in TRM4B display defects in root development and decreased m^5C peaks. TRM4B affects the transcript levels of the genes involved in root development, which is positively correlated with their mRNA stability and m^5C levels. Our results suggest that m^5C in mRNA is a new epitranscriptome marker inArabidopsis, and that regulation of this modification is an integral part of gene regulatory networks underlying plant development.展开更多
Aberrant DNA methylation has raised widespread attention in tumorigenesis. In this study, we aimed to investigate the changes of global DNA methylation and hydroxymethylation from normal to tumor tissues in colorectal...Aberrant DNA methylation has raised widespread attention in tumorigenesis. In this study, we aimed to investigate the changes of global DNA methylation and hydroxymethylation from normal to tumor tissues in colorectal cancer(CRC) and their association with the prognosis. The levels of genomic 5-hydroxymethylcytosine(5hmC) and 5-methylcytosine(5mC) in cancerous tissues were significantly lower than those in corresponding adjacent normal tissues. The genomic levels of 5mC were significantly positively correlated with 5hmC in normal and cancerous tissues(all P<0.05). The ratio of 5mC in cancerous tissues to matched normal tissues(C/N-5mC) was also significantly positively correlated with the ratio of 5hmC in cancerous tissues to matched normal tissues(C/N-5hmC)(P=0.01). The 5mC levels and C/N-5mC ratios decreased with age(all P<0.05). Higher 5mC and 5hmC levels were found in rectal than in colon tissues(all P<0.05). High levels of 5mC in cancerous tissues and high C/N-5hmC ratios were each associated with lymph node metastasis(all P<0.05). Survival analysis indicated that the C/N-5mC ratio(P=0.04) is an independent protective factor for overall survival. The data showed that patients with a combination of high C/N-5hmC and low C/N-5mC ratios tended to have a worse prognosis(P<0.01). Our findings showed that the C/N-5mC ratio may be an independent prognostic factor for CRC outcome. Patients with both a high C/N-5hmC ratio and a low C/N-5mC ratio exhibited the worst survival, suggesting that 5mC and 5hmC can be used as critical markers in tumorigenesis and prognosis estimation.展开更多
背景:溶质载体家族1成员5(solute carrier family 1 member 5,SLC1A5)在多种疾病中发挥了潜在作用,但确切作用机制尚不清楚。构建稳定的SLC1A5过表达和敲低细胞模型可为深入研究SLC1A5在疾病中的确切作用机制以及发现潜在治疗靶点提供...背景:溶质载体家族1成员5(solute carrier family 1 member 5,SLC1A5)在多种疾病中发挥了潜在作用,但确切作用机制尚不清楚。构建稳定的SLC1A5过表达和敲低细胞模型可为深入研究SLC1A5在疾病中的确切作用机制以及发现潜在治疗靶点提供有力的实验工具。目的:构建小鼠SLC1A5过表达和敲低的慢病毒载体,以建立稳定转染的RAW264.7细胞株,为深入探讨SLC1A5在炎症中的作用提供实验基础。方法:根据SLC1A5基因序列设计合成引物并使用聚合酶链反应扩增该基因片段。将目的基因定向接入经Age I/Nhe I酶切的载体质粒GV492中构建重组慢病毒质粒,对阳性克隆进一步筛选后测序比对结果;pHelper1.0质粒载体、pHelper2.0质粒载体、目的质粒载体与293T细胞共同培养并转染,获得慢病毒原液进行包装和滴度测定;在此基础上,通过体外培养RAW264.7细胞,确定嘌呤霉素工作质量浓度;不同滴度的慢病毒分别与RAW264.7细胞共同培养,根据荧光强度确定转染效率;用嘌呤霉素挑选出稳定转染细胞,实时荧光定量聚合酶链反应和蛋白免疫印迹方法检测稳定转染细胞株的SLC1A5基因和蛋白表达水平。结果与结论:(1)测序序列与目的序列一致提示重组慢病毒载体构建成功;(2)过表达SLC1A5慢病毒的滴度为1×10~9 TU/mL,敲低SLC1A5慢病毒的滴度为3×10~9 TU/mL;(3)确定RAW264.7细胞嘌呤霉素工作质量浓度为3μg/mL;(4)过表达/敲低SLC1A5慢病毒转染RAW264.7细胞的最佳条件皆为HiTransG P转染增强液且感染复数值等于50;(5)过表达SLC1A5稳转细胞株中SLC1A5基因和蛋白的表达量明显上调,而敲低SLC1A5稳转细胞株中SLC1A5基因和蛋白的表达量显著下调。结果表明,成功构建了小鼠SLC1A5过表达和敲低的慢病毒载体并获得稳定转染的RAW264.7细胞株。展开更多
Exposure of airborne particulate matter(PM)with an aerodynamic diameter less than 2.5μm(PM2.5)is epidemiologically associated with lung dysfunction and respiratory symptoms,including pulmonary fibrosis.However,whethe...Exposure of airborne particulate matter(PM)with an aerodynamic diameter less than 2.5μm(PM2.5)is epidemiologically associated with lung dysfunction and respiratory symptoms,including pulmonary fibrosis.However,whether epigenetic mechanisms are involved in PM2.5-induced pulmonary fibrosis is currently poorly understood.Herein,using a PM2.5-induced pulmonary fibrosis mouse model,we found that PM2.5 exposure leads to aberrant mRNA5-methylcytosine(m5C)gain and loss in fibrotic lung tissues.Moreover,we showed the m5C-mediated regulatory map of gene functions in pulmonary fibrosis after PM2.5 exposure.Several genes act as m5C gain-upregulated factors,probably critical for the development of PM2.5-induced fibrosis in mouse lungs.These genes,including Lcn2,Mmp9,Chi3l1,Adipoq,Atp5j2,Atp5l,Atpif1,Ndufb6,Fgr,Slc11 a1,and Tyrobp,are highly related to oxidative stress response,inflammatory responses,and immune system processes.Our study illustrates the first epitranscriptomic RNA m5C profile in PM2.5-induced pulmonary fibrosis and will be valuable in identifying biomarkers for PM2.5 exposure-related lung pathogenesis with translational potential.展开更多
Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles an...Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles and their fusion with the cellular membrane. Rab5 has been reported to play an important role in the development of the zebrafish embryo;however, its role in axonal regeneration in the central nervous system remains unclear. In this study, we established a zebrafish Mauthner cell model of axonal injury using single-cell electroporation and two-photon axotomy techniques. We found that overexpression of Rab5 in single Mauthner cells promoted marked axonal regeneration and increased the number of intra-axonal transport vesicles. In contrast, treatment of zebrafish larvae with the Rab kinase inhibitor CID-1067700markedly inhibited axonal regeneration in Mauthner cells. We also found that Rab5 activated phosphatidylinositol 3-kinase(PI3K) during axonal repair of Mauthner cells and promoted the recovery of zebrafish locomotor function. Additionally, rapamycin, an inhibitor of the mechanistic target of rapamycin downstream of PI3K, markedly hindered axonal regeneration. These findings suggest that Rab5 promotes the axonal regeneration of injured zebrafish Mauthner cells by activating the PI3K signaling pathway.展开更多
BACKGROUND C-X-C chemokine receptor type 5(CXCR5)+CD8+T cells represent a unique immune subset with dual roles,functioning as cytotoxic cells in persistent viral infections while promoting B cell responses.Despite the...BACKGROUND C-X-C chemokine receptor type 5(CXCR5)+CD8+T cells represent a unique immune subset with dual roles,functioning as cytotoxic cells in persistent viral infections while promoting B cell responses.Despite their importance,the specific role of CXCR5+CD8+T cells in chronic hepatitis B(CHB),particularly during interferon-alpha(IFN-α)treatment,is not fully understood.This study aims to elucidate the relationship between CXCR5+CD8+T cells and sustained serologic response(SR)in patients undergoing 48 weeks of pegylated IFN-α(peg-IFN-α)treatment for CHB.AIM To elucidate the relationship between CXCR5+CD8+T cells and sustained SR in patients undergoing 48 weeks of peg-IFN-αtreatment for CHB.METHODS This study enrolled 60 patients with hepatitis Be antigen(HBeAg)-positive CHB undergoing 48 weeks of peg-IFN-αtreatment.Participants were assessed for eligibility based on criteria such as persistent HBsAg-positive status for at least six months,HBeAb-negative,hepatitis B virus DNA levels exceeding 2×104 copies/mL,and alanine aminotransferase(ALT)levels between 2 and 10 times the upper limit of normal.Blood samples were collected at baseline and at weeks 12,24,48,and a 24-week treatment-free follow-up(week 72)to measure serum interleukin(IL)-21 concentration via ELISA and to analyze CXCR5 and programmed death-ligand 1(PD-L1)expression on CD8+T cells by flow cytometry,CXCR5 is a chemokine receptor that directs immune cells to specific tissues,while PD-L1 is a protein that regulates immune responses by inhibiting T cell activity.RESULTS Patients with CHB exhibited significantly lower levels of circulating CXCR5+CD8+T cells compared to healthy controls(P<0.01).Notably,CXCR5+CD8+T cells were prominently expressed in patients who achieved sustained SR compared to non-SR(NSR).A significant correlation was observed between CXCR5 and PD-L1 expression(r=-0.189,P=0.002).However,there was no significant correlation between serum IL-21 levels and CXCR5+CD8+lymphocytes(r=-0.03,P=0.625)or serum ALT levels(r=0.026,P=0.678).CONCLUSION The enhanced expression of CXCR5+CD8+T cells in patients achieving HBeAg seroconversion during IFN-αtreatment suggests that these cells play a crucial role in antiviral immune responses against hepatitis B.This study highlights the potential of CXCR5+CD8+T cells as immune regulators in CHB,which may inform future therapeutic strategies to optimize antiviral treatments.展开更多
Microglia,the resident monocyte of the central nervous system,play a crucial role in the response to spinal cord injury.However,the precise mechanism remains unclear.To investigate the molecular mechanisms by which mi...Microglia,the resident monocyte of the central nervous system,play a crucial role in the response to spinal cord injury.However,the precise mechanism remains unclear.To investigate the molecular mechanisms by which microglia regulate the neuroinflammatory response to spinal cord injury,we performed single-cell RNA sequencing dataset analysis,focusing on changes in microglial subpopulations.We found that the MG1 subpopulation emerged in the acute/subacute phase of spinal cord injury and expressed genes related to cell pyroptosis,sphingomyelin metabolism,and neuroinflammation at high levels.Subsequently,we established a mouse model of contusive injury and performed intrathecal injection of siRNA and molecular inhibitors to validate the role of ceramide synthase 5 in the neuroinflammatory responses and pyroptosis after spinal cord injury.Finally,we established a PC12-BV2 cell co-culture system and found that ceramide synthase 5 and pyroptosis-associated proteins were highly expressed to induce the apoptosis of neuron cells.Inhibiting ceramide synthase 5 expression in a mouse model of spinal cord injury effectively reduced pyroptosis.Furthermore,ceramide synthase 5-induced pyroptosis was dependent on activation of the NLRP3 signaling pathway.Inhibiting ceramide synthase 5 expression in microglia in vivo reduced neuronal apoptosis and promoted recovery of neurological function.Pla2g7 formed a“bridge”between sphingolipid metabolism and ceramide synthase 5-mediated cell death by inhibiting the NLRP3 signaling pathway.Collectively,these findings suggest that inhibiting ceramide synthase 5 expression in microglia after spinal cord injury effectively suppressed microglial pyroptosis mediated by NLRP3,thereby exerting neuroprotective effects.展开更多
5-Methylcytosine(m^(5)C)is one of the most prevalent internal modifications of messenger RNA(mRNA)in higher eukaryotes.Here we report that Y box protein 2(YBX2)serves as a novel mammalian m^(5)C binding protein to und...5-Methylcytosine(m^(5)C)is one of the most prevalent internal modifications of messenger RNA(mRNA)in higher eukaryotes.Here we report that Y box protein 2(YBX2)serves as a novel mammalian m^(5)C binding protein to undergo liquid-liquid phase separation(LLPS)both in vivo and in vitro,and this YBX2-dependent LLPS is enhanced by m^(5)C marked RNA.Furthermore,the crystal structure assay revealed that W100,as a distinct m^(5)C binding site of YBX2,is critical in mediating YBX2 phase separation.Our study resolved the relationship between RNA m^(5)C and phase separation,providing a clue for a new regulatory layer of epigenetics.展开更多
基金the Chinese Scholarship Council(Grant No.202206240086)the National Natural Science Foundation of China(Grant No.82170432)programs from Science and Technology Department of Sichuan Province(Grant No.2020YFSY0024).
文摘The incre asing interest in RNA modifications has signifcantly advanced epigenomic and epitranscriptomic technologies.This study focuses on the immuno oncological impact of ALYREF in human cancer through a pan-cancer analysis,enhancing understanding of this gene's role in cancer.We observed differential ALYREF expression between tumor and normal samples,correl ating strongly with prognosis in various cancers,particularly kidney renal papillary cell carcinoma(KIRP)and liver hepatocellular carcinoma(LIHC).ALYREF showed a negative correlation with most tumor-infitrating cells in lung squamous cell carcinoma(LUSC)and lymphoid neoplasm difuse large B-cell lymphoma(DLBC),while positive correlations were noted in IIHC,kidney chromophobe(KICH),mesothelioma(MESO),KIRP,pheochromocytoma and paraganglioma(PARD),and glioma(GBMLGG).Aditionally,ALYREF expression was closely associated with tumor heterogeneity,stemness indices,and a high mutation rate in TP53 across these cancers.In conclusion,ALYREF may serve as an oncogenic biomarker in numerous cancers,meriting further research attention.
文摘5-Methylcytosine (m^5C) is a well-characterized DNA modification, and is also predominantly reported in abundant non-coding RNAs in both prokaryotes and eukaryotes. However, the distribution and biological functions of m^5C in plant mRNAs remain largely unknown. Here, we report transcriptome-wide profiling of RNA m^5C in Arabidopsis thaliana by applying m^5C RNA immunoprecipitation followed by a deep- sequencing approach (m^5C-RIP-seq). LC-MS/MS and dot blot analyses reveal a dynamic pattern of m^5C mRNA modification in various tissues and at different developmental stages, m^5C-RIP-seq analysis identified 6045 m^5C peaks in 4465 expressed genes in young seedlings. We found that m^5C is enriched in coding sequences with two peaks located immediately after start codons and before stop codons, and is associated with mRNAs with low translation activity. We further demonstrated that an RNA (cytosine-5)-methyl- transferase, tRNA-specific methyltransferase 4B (TRM4B), exhibits m^5C RNA methyltransferase activity. Mutations in TRM4B display defects in root development and decreased m^5C peaks. TRM4B affects the transcript levels of the genes involved in root development, which is positively correlated with their mRNA stability and m^5C levels. Our results suggest that m^5C in mRNA is a new epitranscriptome marker inArabidopsis, and that regulation of this modification is an integral part of gene regulatory networks underlying plant development.
基金Project supported by the 111 Project(No.B13026)the National High-Tech R&D Program(863)of China(No.2012AA02A601)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Zhejiang Provincial Program for the Cultivation of High-Level Innovative Health Talents
文摘Aberrant DNA methylation has raised widespread attention in tumorigenesis. In this study, we aimed to investigate the changes of global DNA methylation and hydroxymethylation from normal to tumor tissues in colorectal cancer(CRC) and their association with the prognosis. The levels of genomic 5-hydroxymethylcytosine(5hmC) and 5-methylcytosine(5mC) in cancerous tissues were significantly lower than those in corresponding adjacent normal tissues. The genomic levels of 5mC were significantly positively correlated with 5hmC in normal and cancerous tissues(all P<0.05). The ratio of 5mC in cancerous tissues to matched normal tissues(C/N-5mC) was also significantly positively correlated with the ratio of 5hmC in cancerous tissues to matched normal tissues(C/N-5hmC)(P=0.01). The 5mC levels and C/N-5mC ratios decreased with age(all P<0.05). Higher 5mC and 5hmC levels were found in rectal than in colon tissues(all P<0.05). High levels of 5mC in cancerous tissues and high C/N-5hmC ratios were each associated with lymph node metastasis(all P<0.05). Survival analysis indicated that the C/N-5mC ratio(P=0.04) is an independent protective factor for overall survival. The data showed that patients with a combination of high C/N-5hmC and low C/N-5mC ratios tended to have a worse prognosis(P<0.01). Our findings showed that the C/N-5mC ratio may be an independent prognostic factor for CRC outcome. Patients with both a high C/N-5hmC ratio and a low C/N-5mC ratio exhibited the worst survival, suggesting that 5mC and 5hmC can be used as critical markers in tumorigenesis and prognosis estimation.
基金supported by the State Key Program of the National Natural Science Foundation of China(Grant No.91643206)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB14030300)the Chinese Academy of Sciences/State Administration of Foreign Experts Affairs(CAS/SAFEA)International Partnership Program for Creative Research Teams of China
文摘Exposure of airborne particulate matter(PM)with an aerodynamic diameter less than 2.5μm(PM2.5)is epidemiologically associated with lung dysfunction and respiratory symptoms,including pulmonary fibrosis.However,whether epigenetic mechanisms are involved in PM2.5-induced pulmonary fibrosis is currently poorly understood.Herein,using a PM2.5-induced pulmonary fibrosis mouse model,we found that PM2.5 exposure leads to aberrant mRNA5-methylcytosine(m5C)gain and loss in fibrotic lung tissues.Moreover,we showed the m5C-mediated regulatory map of gene functions in pulmonary fibrosis after PM2.5 exposure.Several genes act as m5C gain-upregulated factors,probably critical for the development of PM2.5-induced fibrosis in mouse lungs.These genes,including Lcn2,Mmp9,Chi3l1,Adipoq,Atp5j2,Atp5l,Atpif1,Ndufb6,Fgr,Slc11 a1,and Tyrobp,are highly related to oxidative stress response,inflammatory responses,and immune system processes.Our study illustrates the first epitranscriptomic RNA m5C profile in PM2.5-induced pulmonary fibrosis and will be valuable in identifying biomarkers for PM2.5 exposure-related lung pathogenesis with translational potential.
基金supported by the Research Funds of the Center for Advanced Interdisciplinary Science and Biomedicine of IHM,No.QYZD20220002the National Natural Science Foundation of China,No.82071357a grant from the Ministry of Science and Technology of China,No.2019YFA0405600 (all to BH)。
文摘Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles and their fusion with the cellular membrane. Rab5 has been reported to play an important role in the development of the zebrafish embryo;however, its role in axonal regeneration in the central nervous system remains unclear. In this study, we established a zebrafish Mauthner cell model of axonal injury using single-cell electroporation and two-photon axotomy techniques. We found that overexpression of Rab5 in single Mauthner cells promoted marked axonal regeneration and increased the number of intra-axonal transport vesicles. In contrast, treatment of zebrafish larvae with the Rab kinase inhibitor CID-1067700markedly inhibited axonal regeneration in Mauthner cells. We also found that Rab5 activated phosphatidylinositol 3-kinase(PI3K) during axonal repair of Mauthner cells and promoted the recovery of zebrafish locomotor function. Additionally, rapamycin, an inhibitor of the mechanistic target of rapamycin downstream of PI3K, markedly hindered axonal regeneration. These findings suggest that Rab5 promotes the axonal regeneration of injured zebrafish Mauthner cells by activating the PI3K signaling pathway.
基金Supported by Changsha Science and Technology Program,No.kq2022397Natural Science Foundation of Hunan Province(Departmental Joint Fund),No.2023JJ60440+2 种基金Research Program of Health Commission of Hunan Province,No.202303088786Clinical Medical Research Center for Viral Hepatitis of Hunan Province,No.2023SK4009the Scientific Research Program of FuRong Laboratory,No.2023SK2108.
文摘BACKGROUND C-X-C chemokine receptor type 5(CXCR5)+CD8+T cells represent a unique immune subset with dual roles,functioning as cytotoxic cells in persistent viral infections while promoting B cell responses.Despite their importance,the specific role of CXCR5+CD8+T cells in chronic hepatitis B(CHB),particularly during interferon-alpha(IFN-α)treatment,is not fully understood.This study aims to elucidate the relationship between CXCR5+CD8+T cells and sustained serologic response(SR)in patients undergoing 48 weeks of pegylated IFN-α(peg-IFN-α)treatment for CHB.AIM To elucidate the relationship between CXCR5+CD8+T cells and sustained SR in patients undergoing 48 weeks of peg-IFN-αtreatment for CHB.METHODS This study enrolled 60 patients with hepatitis Be antigen(HBeAg)-positive CHB undergoing 48 weeks of peg-IFN-αtreatment.Participants were assessed for eligibility based on criteria such as persistent HBsAg-positive status for at least six months,HBeAb-negative,hepatitis B virus DNA levels exceeding 2×104 copies/mL,and alanine aminotransferase(ALT)levels between 2 and 10 times the upper limit of normal.Blood samples were collected at baseline and at weeks 12,24,48,and a 24-week treatment-free follow-up(week 72)to measure serum interleukin(IL)-21 concentration via ELISA and to analyze CXCR5 and programmed death-ligand 1(PD-L1)expression on CD8+T cells by flow cytometry,CXCR5 is a chemokine receptor that directs immune cells to specific tissues,while PD-L1 is a protein that regulates immune responses by inhibiting T cell activity.RESULTS Patients with CHB exhibited significantly lower levels of circulating CXCR5+CD8+T cells compared to healthy controls(P<0.01).Notably,CXCR5+CD8+T cells were prominently expressed in patients who achieved sustained SR compared to non-SR(NSR).A significant correlation was observed between CXCR5 and PD-L1 expression(r=-0.189,P=0.002).However,there was no significant correlation between serum IL-21 levels and CXCR5+CD8+lymphocytes(r=-0.03,P=0.625)or serum ALT levels(r=0.026,P=0.678).CONCLUSION The enhanced expression of CXCR5+CD8+T cells in patients achieving HBeAg seroconversion during IFN-αtreatment suggests that these cells play a crucial role in antiviral immune responses against hepatitis B.This study highlights the potential of CXCR5+CD8+T cells as immune regulators in CHB,which may inform future therapeutic strategies to optimize antiviral treatments.
基金supported by grants from the National Key Research and Development Program of China,No.2017YFA0105400(to LR)the Key Research and Development Program of Guangdong Province,No.2019B020236002(to LR)the National Natural Science Foundation of China,Nos.81972111(to LZ),81772349(to BL).
文摘Microglia,the resident monocyte of the central nervous system,play a crucial role in the response to spinal cord injury.However,the precise mechanism remains unclear.To investigate the molecular mechanisms by which microglia regulate the neuroinflammatory response to spinal cord injury,we performed single-cell RNA sequencing dataset analysis,focusing on changes in microglial subpopulations.We found that the MG1 subpopulation emerged in the acute/subacute phase of spinal cord injury and expressed genes related to cell pyroptosis,sphingomyelin metabolism,and neuroinflammation at high levels.Subsequently,we established a mouse model of contusive injury and performed intrathecal injection of siRNA and molecular inhibitors to validate the role of ceramide synthase 5 in the neuroinflammatory responses and pyroptosis after spinal cord injury.Finally,we established a PC12-BV2 cell co-culture system and found that ceramide synthase 5 and pyroptosis-associated proteins were highly expressed to induce the apoptosis of neuron cells.Inhibiting ceramide synthase 5 expression in a mouse model of spinal cord injury effectively reduced pyroptosis.Furthermore,ceramide synthase 5-induced pyroptosis was dependent on activation of the NLRP3 signaling pathway.Inhibiting ceramide synthase 5 expression in microglia in vivo reduced neuronal apoptosis and promoted recovery of neurological function.Pla2g7 formed a“bridge”between sphingolipid metabolism and ceramide synthase 5-mediated cell death by inhibiting the NLRP3 signaling pathway.Collectively,these findings suggest that inhibiting ceramide synthase 5 expression in microglia after spinal cord injury effectively suppressed microglial pyroptosis mediated by NLRP3,thereby exerting neuroprotective effects.
基金the National Natural Science Foundation of China(Grants No.32030058,91940302,91940304,91940000 and 92053115)the fellowship of China Postdoctoral Science Foundation(Grant No.2020M670986)+3 种基金the National Key R&D Program of China(Grants No.2018YFA0109700,2019YFA0801702 and 2019YFA0802201)Beijing Nova Program(Grant No.Z201100006820104)the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.CAS2018133)the Open Research Fund of the National Center for Protein Sciences at Peking University in Beijing.We thank the National Center for Protein Science Shanghai for their instrumental support and technical assistance.We thank the staff from the BL18U1 beamline at Shanghai Synchrotron Radiation Facility for assistance during data collection.
文摘5-Methylcytosine(m^(5)C)is one of the most prevalent internal modifications of messenger RNA(mRNA)in higher eukaryotes.Here we report that Y box protein 2(YBX2)serves as a novel mammalian m^(5)C binding protein to undergo liquid-liquid phase separation(LLPS)both in vivo and in vitro,and this YBX2-dependent LLPS is enhanced by m^(5)C marked RNA.Furthermore,the crystal structure assay revealed that W100,as a distinct m^(5)C binding site of YBX2,is critical in mediating YBX2 phase separation.Our study resolved the relationship between RNA m^(5)C and phase separation,providing a clue for a new regulatory layer of epigenetics.