Objective To investigate whether genes required for synaptogenesis and synaptic function are also involved in fat storage control in Caenorhabditis elegans. Methods Fat storage was examined in mutants of genes affecti...Objective To investigate whether genes required for synaptogenesis and synaptic function are also involved in fat storage control in Caenorhabditis elegans. Methods Fat storage was examined in mutants of genes affecting the synaptogenesis and synaptic function. In addition, the genetic interactions of SNAREs syntaxin/unc-64 and SNAP-25/ric-4 with daf-2, daf-7, nhr-49, sbp-1 and mdt-15 in regulating fat storage were further investigated. The tissue-specific activities of unc-64 and ric-4 were investigated to study the roles of unc-64 and ric-4 in regulating fat storage in the nervous system and/or the intestine. Results Mutations of genes required for the formation of presynaptic neurotransmission site did not obviously influence fat storage. However, among the genes required for synaptic function, the plasma membrane-associated SNAREs syntaxin/unc-64 and SNAP-25/ric-4 genes were involved in the fat storage control. Fat storage in the intestinal cells was dramatically increased in unc-64 and ric-4 mutants as revealed by Sudan Black and Nile Red strainings, although the fat droplet size was not significantly changed. Moreover, in both the nervous system and the intestine, expression of unc-64 significantly inhibited the increase in fat storage observed in unc-64 mutant. And expression of ric-4 in the nervous system completely restored fat storage in ric-4 mutant. Genetic interaction assay further indicated that both unc-64 and ric-4 regulated fat storage independently of daf-2 [encoding an insulin-like growth factor-I （IGF-I） receptor], daf-7 [encoding a transforming growth factor-β （TGF-β） ligand], and nhr-49 （encoding a nuclear hormone receptor）. Besides, mutation of daf-16 did not obviously affect the phenotype of increased fat storage in unc-64 or ric-4 mutant. Furthermore, unc-64 and ric-4 regulated fat storage probably through the ARC105/mdt-15- and SREBP/sbp-1-mediated signaling pathways. In addition, fat storage in unc-64; ric-4 was higher than that in either unc-64 or ric-4 single mutant nematodes, suggesting that unc-64 functions in parallel with ric-4 in regulating fat storage. Conclusion The plasma membrane-associated SNAREs syntaxin/ unc-64 and SNAP-25/ric-4 function in parallel in regulating fat storage in C. elegans, probably through the ARC105/mdt-15- and SREBP/sbp-1-mediated signaling pathways.展开更多
Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the inte...Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the intestinal autofluorescence of unc-13 and sbt-1 mutants were examined at different temperature conditions. In addition, to exclude the possible influences from other factors in unc-13 and sbt-1 mutants, the dauer formation, the thermotaxis, the brood size and the population percentage of the mutants expressing hsp16.2-gfp were further investigated. Results Mutations of unc-13 and sbt-1 significantly increased the mean and the maximum lifespans of nematodes cultured at 20 oC and 25 oC, while no noticeable increase was found at 15 oC in either the mean or the maximum lifespan. Investigations on the speed of pharynx pumping and the intestinal autofluorescence suggested that at 20 oC and 25 oC, mutations of unc-13 and sbt-1 could slow the aging process and delay the accumulation of aging-related cellular damage. Meanwhile, mutations of unc-13 or sbt-1 did not affect the dauer formation or the thermotaxis to different temperatures in nematodes. In contrast, at 20 oC and 25 oC conditions, mutations of unc-13 and sbt-1 significantly decreased the brood size and the percentage of nematodes expressing hsp16.2-gfp, while no such differences were detected at 15 oC. Moreover, the thermotolerance of unc-13 and sbt-1 mutants could be greatly strengthened after the 16-h heat shock at 35 oC. Conclusion The regulation of aging by unc-13 and sbt-1 is temperature-dependent. And the alterations in reproduction capability and stress response may be associated with the formation of this temperature-dependent property.展开更多
目的研究依赖性受体Unc5H4诱导人神经母细胞瘤(neuroblastoma,NB)细胞系SH-SY5Y细胞凋亡而其配体Netrin-1抑制其凋亡诱导的作用。方法人NB细胞系SH-SY5Y细胞中转染Unc5H4质粒,在有/无配体Netrin-1作用下进行平板克隆形成实验,探讨Unc5H...目的研究依赖性受体Unc5H4诱导人神经母细胞瘤(neuroblastoma,NB)细胞系SH-SY5Y细胞凋亡而其配体Netrin-1抑制其凋亡诱导的作用。方法人NB细胞系SH-SY5Y细胞中转染Unc5H4质粒,在有/无配体Netrin-1作用下进行平板克隆形成实验,探讨Unc5H4是否诱导细胞凋亡以及诱导细胞凋亡作用是否受Netrin-1蛋白作用的影响。进一步在SH-SY5Y细胞中表达Unc5H4,在阿霉素(ADR)刺激下,在有/无配体Netrin-1蛋白作用时检测Unc5H4蛋白条带的变化,即Unc5H4释放死亡结构域后的截断蛋白诱导细胞凋亡的变化。结果 Caspase-3活性检测结果显示,过表达Unc5H4可诱导SH-SY5Y细胞发生凋亡,其相对Caspase-3活性(180%±20%)明显高于对照组(100%),差异有显著统计学意义(P?0.01)。而加入Netrin-1组细胞的相对Caspase-3活性(112%±14%)明显低于无Netrin-1组(180%?20%),差异有统计学意义(P?0.01),与对照组(100%)相比差异无统计学意义。SH-SY5Y细胞中转染Unc5H4质粒,在同时受到ADR诱导的DNA损伤时,在无Netrin-1蛋白作用下,可以检测到Unc5H4截断蛋白(酶切死亡结构域,60 k Da)的表达,而Netrin-1能够阻止Unc5H4蛋白的截断,从而阻止其诱导凋亡的作用。结论依赖性受体Unc5H4能够诱导人NB细胞凋亡,其配体Netrin-1能够通过阻止其发生蛋白截断而抑制其诱导凋亡的功能,从而使NB细胞获得增殖。展开更多
目的探讨UNC5H3和DCC在胃癌组织的表达,与临床病理特征和增殖的关系以及与患者生存和预后的关系。方法应用组织芯片和免疫组织化学技术,分析60例胃癌组织中UNC5H3、DCC和Ki-67的表达,并对其表达进行相关分析。利用图像分析软件Image-Pro...目的探讨UNC5H3和DCC在胃癌组织的表达,与临床病理特征和增殖的关系以及与患者生存和预后的关系。方法应用组织芯片和免疫组织化学技术,分析60例胃癌组织中UNC5H3、DCC和Ki-67的表达,并对其表达进行相关分析。利用图像分析软件Image-Pro Plus 6.0测量切片积分吸光度,对结果进行验证。采用Kaplan-Meier限乘法计算生存率。建立Cox回归模型,评价UNC5H3和DCC作为胃癌患者预后的独立影响因素的可行性。结果在60例胃癌组织中,UNC5H3、DCC和Ki-67的阳性表达率分别为43.3%、53.3%和60.0%。UNC5H3和DCC与淋巴转移和远处转移之间,差异有显著性(P<0.05)。UNC5H3和DCC表达与Ki-67表达相互之间无相关性(P>0.05)。用Kaplan-Meier生存曲线经Log-rank检验发现,UNC5H3的阳性表达与胃癌患者生存之间存在相关性(P<0.05)。DCC的阳性表达与胃癌患者生存之间无相关性(P>0.05)。经Cox回归分析,UNC5H3和DCC的表达与胃癌患者预后无明显相关性。结论依赖性受体UNC5H3和DCC共同参与了胃癌的发生进展,检测UNC5H3和DCC可作为反映胃癌临床病理学特点的指标,检测UNC5H3可作为胃癌患者生存期的指标,但UNC5H3和DCC的表达不是判断胃癌患者预后的独立影响因素。展开更多
基金supported by the grants from the National Natural Science Foundation of China(No. 30771113, 30870810)the Program for New Century Excellent Talents in University
文摘Objective To investigate whether genes required for synaptogenesis and synaptic function are also involved in fat storage control in Caenorhabditis elegans. Methods Fat storage was examined in mutants of genes affecting the synaptogenesis and synaptic function. In addition, the genetic interactions of SNAREs syntaxin/unc-64 and SNAP-25/ric-4 with daf-2, daf-7, nhr-49, sbp-1 and mdt-15 in regulating fat storage were further investigated. The tissue-specific activities of unc-64 and ric-4 were investigated to study the roles of unc-64 and ric-4 in regulating fat storage in the nervous system and/or the intestine. Results Mutations of genes required for the formation of presynaptic neurotransmission site did not obviously influence fat storage. However, among the genes required for synaptic function, the plasma membrane-associated SNAREs syntaxin/unc-64 and SNAP-25/ric-4 genes were involved in the fat storage control. Fat storage in the intestinal cells was dramatically increased in unc-64 and ric-4 mutants as revealed by Sudan Black and Nile Red strainings, although the fat droplet size was not significantly changed. Moreover, in both the nervous system and the intestine, expression of unc-64 significantly inhibited the increase in fat storage observed in unc-64 mutant. And expression of ric-4 in the nervous system completely restored fat storage in ric-4 mutant. Genetic interaction assay further indicated that both unc-64 and ric-4 regulated fat storage independently of daf-2 [encoding an insulin-like growth factor-I （IGF-I） receptor], daf-7 [encoding a transforming growth factor-β （TGF-β） ligand], and nhr-49 （encoding a nuclear hormone receptor）. Besides, mutation of daf-16 did not obviously affect the phenotype of increased fat storage in unc-64 or ric-4 mutant. Furthermore, unc-64 and ric-4 regulated fat storage probably through the ARC105/mdt-15- and SREBP/sbp-1-mediated signaling pathways. In addition, fat storage in unc-64; ric-4 was higher than that in either unc-64 or ric-4 single mutant nematodes, suggesting that unc-64 functions in parallel with ric-4 in regulating fat storage. Conclusion The plasma membrane-associated SNAREs syntaxin/ unc-64 and SNAP-25/ric-4 function in parallel in regulating fat storage in C. elegans, probably through the ARC105/mdt-15- and SREBP/sbp-1-mediated signaling pathways.
基金supported by grants from the National Natural Science Foundation of China (No.30771113, 30870810)the Program for New Century Excellent Talents in Universitythe Innovative Research Program for Undergraduates in China (No. C2007052)
文摘Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the intestinal autofluorescence of unc-13 and sbt-1 mutants were examined at different temperature conditions. In addition, to exclude the possible influences from other factors in unc-13 and sbt-1 mutants, the dauer formation, the thermotaxis, the brood size and the population percentage of the mutants expressing hsp16.2-gfp were further investigated. Results Mutations of unc-13 and sbt-1 significantly increased the mean and the maximum lifespans of nematodes cultured at 20 oC and 25 oC, while no noticeable increase was found at 15 oC in either the mean or the maximum lifespan. Investigations on the speed of pharynx pumping and the intestinal autofluorescence suggested that at 20 oC and 25 oC, mutations of unc-13 and sbt-1 could slow the aging process and delay the accumulation of aging-related cellular damage. Meanwhile, mutations of unc-13 or sbt-1 did not affect the dauer formation or the thermotaxis to different temperatures in nematodes. In contrast, at 20 oC and 25 oC conditions, mutations of unc-13 and sbt-1 significantly decreased the brood size and the percentage of nematodes expressing hsp16.2-gfp, while no such differences were detected at 15 oC. Moreover, the thermotolerance of unc-13 and sbt-1 mutants could be greatly strengthened after the 16-h heat shock at 35 oC. Conclusion The regulation of aging by unc-13 and sbt-1 is temperature-dependent. And the alterations in reproduction capability and stress response may be associated with the formation of this temperature-dependent property.
文摘目的研究依赖性受体Unc5H4诱导人神经母细胞瘤(neuroblastoma,NB)细胞系SH-SY5Y细胞凋亡而其配体Netrin-1抑制其凋亡诱导的作用。方法人NB细胞系SH-SY5Y细胞中转染Unc5H4质粒,在有/无配体Netrin-1作用下进行平板克隆形成实验,探讨Unc5H4是否诱导细胞凋亡以及诱导细胞凋亡作用是否受Netrin-1蛋白作用的影响。进一步在SH-SY5Y细胞中表达Unc5H4,在阿霉素(ADR)刺激下,在有/无配体Netrin-1蛋白作用时检测Unc5H4蛋白条带的变化,即Unc5H4释放死亡结构域后的截断蛋白诱导细胞凋亡的变化。结果 Caspase-3活性检测结果显示,过表达Unc5H4可诱导SH-SY5Y细胞发生凋亡,其相对Caspase-3活性(180%±20%)明显高于对照组(100%),差异有显著统计学意义(P?0.01)。而加入Netrin-1组细胞的相对Caspase-3活性(112%±14%)明显低于无Netrin-1组(180%?20%),差异有统计学意义(P?0.01),与对照组(100%)相比差异无统计学意义。SH-SY5Y细胞中转染Unc5H4质粒,在同时受到ADR诱导的DNA损伤时,在无Netrin-1蛋白作用下,可以检测到Unc5H4截断蛋白(酶切死亡结构域,60 k Da)的表达,而Netrin-1能够阻止Unc5H4蛋白的截断,从而阻止其诱导凋亡的作用。结论依赖性受体Unc5H4能够诱导人NB细胞凋亡,其配体Netrin-1能够通过阻止其发生蛋白截断而抑制其诱导凋亡的功能,从而使NB细胞获得增殖。
文摘目的探讨UNC5H3和DCC在胃癌组织的表达,与临床病理特征和增殖的关系以及与患者生存和预后的关系。方法应用组织芯片和免疫组织化学技术,分析60例胃癌组织中UNC5H3、DCC和Ki-67的表达,并对其表达进行相关分析。利用图像分析软件Image-Pro Plus 6.0测量切片积分吸光度,对结果进行验证。采用Kaplan-Meier限乘法计算生存率。建立Cox回归模型,评价UNC5H3和DCC作为胃癌患者预后的独立影响因素的可行性。结果在60例胃癌组织中,UNC5H3、DCC和Ki-67的阳性表达率分别为43.3%、53.3%和60.0%。UNC5H3和DCC与淋巴转移和远处转移之间,差异有显著性(P<0.05)。UNC5H3和DCC表达与Ki-67表达相互之间无相关性(P>0.05)。用Kaplan-Meier生存曲线经Log-rank检验发现,UNC5H3的阳性表达与胃癌患者生存之间存在相关性(P<0.05)。DCC的阳性表达与胃癌患者生存之间无相关性(P>0.05)。经Cox回归分析,UNC5H3和DCC的表达与胃癌患者预后无明显相关性。结论依赖性受体UNC5H3和DCC共同参与了胃癌的发生进展,检测UNC5H3和DCC可作为反映胃癌临床病理学特点的指标,检测UNC5H3可作为胃癌患者生存期的指标,但UNC5H3和DCC的表达不是判断胃癌患者预后的独立影响因素。
