The molecular mechanism of DNA damage induced by hydroquinone （HQ） remains unclear. Poly（ADP-ribose） polymerase-1 （PARP-1） usually works as a DNA damage sensor, and hence, it is possible that PARP-1 is involved ...The molecular mechanism of DNA damage induced by hydroquinone （HQ） remains unclear. Poly（ADP-ribose） polymerase-1 （PARP-1） usually works as a DNA damage sensor, and hence, it is possible that PARP-1 is involved in the DNA damage response induced by HQ. In TK6 cells treated with HQ, PARP activity as well as the expression of apoptosis antagonizing transcription factor （AATF）, PARP-1, and phosphorylated H2AX （v-H2AX） were maximum at 0.5 h, 6 h, 3 h, and 3 h, respectively. To explore the detailed mechanisms underlying the prompt DNA repair reaction, the above indicators were investigated in PARP-l-silenced cells. PARP activity and expression of AATF and PARP-1 decreased to 36%, 32%, and 33%, respectively, in the cells; however, y-H2AX expression increased to 265%. Co-immunoprecipitation （co-IP） assays were employed to determine whether PARP-1 and AATF formed protein complexes. The interaction between these proteins together with the results from IP assays and confocal microscopy indicated that poly（ADP-ribosyl）ation {PARylation） regulated AATF expression, in conclusion, PARP-1 was involved in the DNA damage repair induced by HQ via increasing the accumulation of AATF through PARylation.展开更多
DNA damage and the enzyme poly(ADP-ribose)polymerase(PARP)associated with the pathogenesis of numerous age-related neurodegenerative disorders.Astrocytes play crucial roles in both support metabolic functions and cell...DNA damage and the enzyme poly(ADP-ribose)polymerase(PARP)associated with the pathogenesis of numerous age-related neurodegenerative disorders.Astrocytes play crucial roles in both support metabolic functions and cell viability of the brain.PARP regulates DNA damage and repair in the brain cells.In this study PARP activity and DNA strand break were investigated in the astrocytes isolated from young and aged rat brain.Three and 30-month-old rats were killed by decapitation and brains were removed onto an ice cooled glass plate.Astrocytes were isolated by sucrose density gradient centrifugation and glutamine synthetase(GS)served as a marker of the astrocytes lineage.The specific activity of PARP was assayed in permeabilized cells by measuring the incorporation of the ADP-ribose moiety of[3H]NAD into the nuclear acceptor proteins.The rate of DNA strand breaks was determined using a fluorescent dye and monitored spectrofluorimetry.An increase(about 75%)in the PARP activity was observed in the whole homogenates of aged rats,whereas this rise was more pronounced(about 360%)when the reaction was measured in the purified astrocyte preparations.The amount of DNA strand breaks was also higher in the astrocytes isolated from the aged brain as compared to that of young levels.The close relationship between the level of DNA strand breaks and PARP activity in the astrocytes suggest that these cells are susceptible to the metabolic alterations in aging.It is concluded that the astrocytes PARP might be considered as a therapeutic target for combating age related neurodegenerative disorders.展开更多
Poly(ADP-ribosyl)ation(PARylation)is a posttranslational modification reversibly catalyzed by poly(ADP-ribose)polymerases(PARPs)and poly(ADP-ribose)glycohydrolases(PARGs)and plays a key role in multi-ple cellular proc...Poly(ADP-ribosyl)ation(PARylation)is a posttranslational modification reversibly catalyzed by poly(ADP-ribose)polymerases(PARPs)and poly(ADP-ribose)glycohydrolases(PARGs)and plays a key role in multi-ple cellular processes.The molecular mechanisms by which PARylation regulates innate immunity remain largely unknown in eukaryotes.Here we show that Arabidopsis UBC13A and UBC13B,the major drivers of lysine 63(K63)-linked polyubiquitination,directly interact with PARPs/PARGs.Activation of pathogen-associated molecular pattern(PAMP)-triggered immunity promotes these interactions and enhances PARylation of UBC13.Both parp1 parp2 and ubc13a ubc13b mutants are compromised in immune responses with increased accumulation of total pathogenesis-related(PR)proteins but decreased accu-mulation of secreted PR proteins.Protein disulfide-isomerases(PDIs),essential components of endo-plasmic reticulum quality control(ERQC)that ensure proper folding and maturation of proteins destined for secretion,complex with PARPs/PARGs and are PARylated upon PAMP perception.Significantly,PARylation of UBC13 regulates K63-linked ubiquitination of PDIs,which may further promote their disulfide isomerase activities for correct protein folding and subsequent secretion.Taken together,these results indicate that plant immunity is coordinately regulated by PARylation and K63-linked ubiquitination.展开更多
目的采用高分辨融解曲线(HRM)技术建立检测类ADP核糖基化因子GTP酶15(ARL15)、主要组织相容性抗原复合体ⅡDMα(HLA-DMA)和核因子κB亚基2(NFKB2)基因单核苷酸多态性(SNP)的方法,并探讨其与中国西北地区汉族人群类风湿性关节炎(RA)易感...目的采用高分辨融解曲线(HRM)技术建立检测类ADP核糖基化因子GTP酶15(ARL15)、主要组织相容性抗原复合体ⅡDMα(HLA-DMA)和核因子κB亚基2(NFKB2)基因单核苷酸多态性(SNP)的方法,并探讨其与中国西北地区汉族人群类风湿性关节炎(RA)易感性的关系。方法针对rs255758、rs1063478、rs397514331和rs397514332四个SNP位点建立PCRHRM检测体系并测序验证。对588例RA患者和200例健康对照标本进行病例对照研究,分析这四个SNP与RA发病风险的关系。结果建立的针对四个SNP位点的PCR-HRM基因分型方法经测序验证可正确分型。rs397514331和rs397514332位点未发现突变基因型。rs255758和rs1063478位点的基因型频率在两组间存在统计学差异,而基因频率无统计学差异。其中rs255758位点的AA基因型在显性模型(AA vs AC/CC)下降低RA发病风险(OR=0.666,95%CI=0.478~0.927,P=0.016)。结论我们建立的PCR-HRM基因分型方法可对rs255758、rs1063478、rs397514331和rs397514332四个SNP位点进行常规化检测。ARL15和HLA-DMA基因多态性与中国西北地区汉族人群RA易感相关。展开更多
基金supported by grants from the National Natural Science Foundation of China(8120223181273116+2 种基金81430079)the Science and Technology Program of Guangdong Bureau of Science and TechnologyChina(2013B021800069)
文摘The molecular mechanism of DNA damage induced by hydroquinone （HQ） remains unclear. Poly（ADP-ribose） polymerase-1 （PARP-1） usually works as a DNA damage sensor, and hence, it is possible that PARP-1 is involved in the DNA damage response induced by HQ. In TK6 cells treated with HQ, PARP activity as well as the expression of apoptosis antagonizing transcription factor （AATF）, PARP-1, and phosphorylated H2AX （v-H2AX） were maximum at 0.5 h, 6 h, 3 h, and 3 h, respectively. To explore the detailed mechanisms underlying the prompt DNA repair reaction, the above indicators were investigated in PARP-l-silenced cells. PARP activity and expression of AATF and PARP-1 decreased to 36%, 32%, and 33%, respectively, in the cells; however, y-H2AX expression increased to 265%. Co-immunoprecipitation （co-IP） assays were employed to determine whether PARP-1 and AATF formed protein complexes. The interaction between these proteins together with the results from IP assays and confocal microscopy indicated that poly（ADP-ribosyl）ation {PARylation） regulated AATF expression, in conclusion, PARP-1 was involved in the DNA damage repair induced by HQ via increasing the accumulation of AATF through PARylation.
文摘DNA damage and the enzyme poly(ADP-ribose)polymerase(PARP)associated with the pathogenesis of numerous age-related neurodegenerative disorders.Astrocytes play crucial roles in both support metabolic functions and cell viability of the brain.PARP regulates DNA damage and repair in the brain cells.In this study PARP activity and DNA strand break were investigated in the astrocytes isolated from young and aged rat brain.Three and 30-month-old rats were killed by decapitation and brains were removed onto an ice cooled glass plate.Astrocytes were isolated by sucrose density gradient centrifugation and glutamine synthetase(GS)served as a marker of the astrocytes lineage.The specific activity of PARP was assayed in permeabilized cells by measuring the incorporation of the ADP-ribose moiety of[3H]NAD into the nuclear acceptor proteins.The rate of DNA strand breaks was determined using a fluorescent dye and monitored spectrofluorimetry.An increase(about 75%)in the PARP activity was observed in the whole homogenates of aged rats,whereas this rise was more pronounced(about 360%)when the reaction was measured in the purified astrocyte preparations.The amount of DNA strand breaks was also higher in the astrocytes isolated from the aged brain as compared to that of young levels.The close relationship between the level of DNA strand breaks and PARP activity in the astrocytes suggest that these cells are susceptible to the metabolic alterations in aging.It is concluded that the astrocytes PARP might be considered as a therapeutic target for combating age related neurodegenerative disorders.
基金supported by a start-up fund from Texas A&M AgriLife Research to J.S.a grant from the National Science Foundation(IOS-1951094)to P.H.and J.S.
文摘Poly(ADP-ribosyl)ation(PARylation)is a posttranslational modification reversibly catalyzed by poly(ADP-ribose)polymerases(PARPs)and poly(ADP-ribose)glycohydrolases(PARGs)and plays a key role in multi-ple cellular processes.The molecular mechanisms by which PARylation regulates innate immunity remain largely unknown in eukaryotes.Here we show that Arabidopsis UBC13A and UBC13B,the major drivers of lysine 63(K63)-linked polyubiquitination,directly interact with PARPs/PARGs.Activation of pathogen-associated molecular pattern(PAMP)-triggered immunity promotes these interactions and enhances PARylation of UBC13.Both parp1 parp2 and ubc13a ubc13b mutants are compromised in immune responses with increased accumulation of total pathogenesis-related(PR)proteins but decreased accu-mulation of secreted PR proteins.Protein disulfide-isomerases(PDIs),essential components of endo-plasmic reticulum quality control(ERQC)that ensure proper folding and maturation of proteins destined for secretion,complex with PARPs/PARGs and are PARylated upon PAMP perception.Significantly,PARylation of UBC13 regulates K63-linked ubiquitination of PDIs,which may further promote their disulfide isomerase activities for correct protein folding and subsequent secretion.Taken together,these results indicate that plant immunity is coordinately regulated by PARylation and K63-linked ubiquitination.
文摘目的采用高分辨融解曲线(HRM)技术建立检测类ADP核糖基化因子GTP酶15(ARL15)、主要组织相容性抗原复合体ⅡDMα(HLA-DMA)和核因子κB亚基2(NFKB2)基因单核苷酸多态性(SNP)的方法,并探讨其与中国西北地区汉族人群类风湿性关节炎(RA)易感性的关系。方法针对rs255758、rs1063478、rs397514331和rs397514332四个SNP位点建立PCRHRM检测体系并测序验证。对588例RA患者和200例健康对照标本进行病例对照研究,分析这四个SNP与RA发病风险的关系。结果建立的针对四个SNP位点的PCR-HRM基因分型方法经测序验证可正确分型。rs397514331和rs397514332位点未发现突变基因型。rs255758和rs1063478位点的基因型频率在两组间存在统计学差异,而基因频率无统计学差异。其中rs255758位点的AA基因型在显性模型(AA vs AC/CC)下降低RA发病风险(OR=0.666,95%CI=0.478~0.927,P=0.016)。结论我们建立的PCR-HRM基因分型方法可对rs255758、rs1063478、rs397514331和rs397514332四个SNP位点进行常规化检测。ARL15和HLA-DMA基因多态性与中国西北地区汉族人群RA易感相关。
