piR-823 inhibits cell apoptosis via modulating mitophagy by binding to PINK1 in colorectal cancer

Mitophagy plays a vital role in the maintenance of mitochondrial homeostasis and tumorigenesis. Noncoding RNA piR-823 contributes to colorectal tumorigenesis. In this study, we aim to evaluate piR-823-mediated mitophagy and its mechanistic association with colorectal cancer (CRC). Digital gene expression analysis was performed to explore the potential functions of piR-823. A piR-823 antagomir (Ant-823) was used to inhibit piR-823 expression, and piR-823 mimics (mimics-823) were used to increase piR-823 expression. Mitophagy was measured in vivo and in vitro by immunofluorescence and western blot analysis. JC-1 staining, ATP production, real-time PCR, and western blot analysis were used to measure changes in mitochondrial quality and number. siRNA transfection was used to inhibit mitophagy, and CCCP was used to induce mitophagy. RNA pull-down assays and RNA-binding protein immunoprecipitation assays were conducted to investigate the molecular mechanisms. Here, we found that CRC cells transfected with Ant-823 presented an altered expression of autophagic and mitophagy genes by Digital gene expression analysis. Ant-823 could promote Parkin activation and mitophagy in vitro and in vivo, followed by mitochondrial loss and dysfunction of some mitochondria, whereas mimics-823 exerted the opposite effects in CRC cells. The inhibition of mitophagy by siParkin alleviated Ant-823-induced mitochondrial loss and dysfunction, as well as apoptosis to a certain extent. Furthermore, piR-823 was found to interact with PINK1 and promote its ubiquitination and proteasome-dependent degradation, thus alleviating mitophagy. Finally, these findings were verifed in samples obtained by patients affected by colorectal cancer. In conclusion, we identify a novel mechanism by which piR-823 regulates mitophagy during CRC tumorigenesis by increasing PINK1 degradation. Subject terms: Colorectal cancer, Gastrointestinal cancer     

鄱阳湖湿地不同土地利用方式下土壤微生物群落功能多样性

于2011年5月分别采集鄱阳湖围垦92、48a和38a的水稻田,退田还湖25a的退耕地以及自然湿地共5个样地的表层土壤,利用Biolog-ECO板技术对土壤微生物群落的单一碳源利用情况进行了测定,并结合群落指数和主成分分析(PCA)对培养72 h土壤微生物群落功能多样性变化进行了分析。结果表明:退耕地和自然湿地土壤微生物群落利用31种碳源的能力较强,来自不同围垦年限的土壤微生物群落利用碳源能力均较弱;且随围垦时间的增长,土壤微生物对碳源的利用能力呈降低的趋势。自然湿地、退耕地与围垦92、38a样地土壤之间存在显著的微生物功能多样性差异;围垦对土壤微生物代谢糖类、羧酸类、氨基酸类物质的影响最为明显。结果提示,围垦改变了湿地土壤微生物群落结构,退田还湖有助于湿地土壤微生物群落结构的恢复。     

Using genetic variation to disentangle the complex relationship between food intake and health outcomes

Diet is considered as one of the most important modifiable factors influencing human health, but efforts to identify foods or dietary patterns associated with health outcomes often suffer from biases, confounding, and reverse causation. Applying Mendelian randomization in this context may provide evidence to strengthen causality in nutrition research. To this end, we first identified 283 genetic markers associated with dietary intake in 445,779 UK Biobank participants. We then converted these associations into direct genetic effects on food exposures by adjusting them for effects mediated via other traits. The SNPs which did not show evidence of mediation were then used for MR, assessing the association between genetically predicted food choices and other risk factors, health outcomes. We show that using all associated SNPs without omitting those which show evidence of mediation, leads to biases in downstream analyses (genetic correlations, causal inference), similar to those present in observational studies. However, MR analyses using SNPs which have only a direct effect on the exposure on food exposures provided unequivocal evidence of causal associations between specific eating patterns and obesity, blood lipid status, and several other risk factors and health outcomes.     

不同花生品种对旱涝胁迫的响应及生理机制

为评价花生对旱、涝胁迫的响应,本试验以4个旱、涝耐性差异明显的花生品种为材料,运用温室防雨盆栽方法,在苗期、花针期分别进行正常灌溉(对照)、干旱(7d,叶片萎蔫)、根部淹涝(土面水深2 cm,时间1d、3d、7d)和整株淹涝(水深至苗顶,时间1d、3d、7d)的处理,测定地上部及根系生物量、根冠比、根系活力、叶片超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量。结果表明,苗期、花针期干旱均抑制地上部生长,提高根冠比;苗期干旱降低根系生物量,而花针期增加。2个时期淹涝均促进地上部生长、抑制根系生长、降低根冠比,并随淹水加深、延时而加重。旱、涝条件下根系活力均降低,SOD、MDA呈上升趋势。遭受相同时间(7d)的水分胁迫后,危害程度以干旱重于淹涝,花针期重于苗期。基于生物量、生理指标变化的综合分析进一步表明,4个花生品种的旱、涝耐性差异很大,湘花55号耐旱性强、耐涝性弱,豫花15号耐旱性弱、耐涝性强,中花4号耐旱、涝性均最弱,中花8号耐旱、涝性均最强。     

莱州湾中国对虾生长特性及其空间分布

根据2010年5月—10月调查资料,对山东莱州湾中国对虾(Fenneropenaeus chinensis)的资源状况、生长特性及其空间分布进行了研究。莱州湾放流前本底调查资料表明,目前山东莱州湾中国对虾捕捞产量主要来源于增殖放流,且在一定条件下捕捞产量与放流数量成正相关关系。依据2010年中国对虾生物学数据,应用R语言命令对中国对虾体长体重关系和体长生长方程进行了拟合,并对拟合系数进行了显著性检验,结果表明中国对虾体长与体重系数a、b处于显著水平(P0.05),中国对虾体长生长方程拟合系数K、t_0、L_∞处于极显著水平(P0.001),故拟合效果明显,获得为中国对虾生长参数雌虾为K=0.0226、t_0=37.45d、L_∞=200.77 mm、W_∞=80.50 g、t_r=85.18d(8月4日),雄虾为:K=0.0419、t_0=40.25d、L_∞=145.81 mm、W_∞=23.37 g、tr=67.24d(7月18日),与20世纪80年代相比,中国对虾个体明显减小,生长速度加快,生长拐点提前了1个月。另外,根据大面调查体长数据,对各个站位体长组出现频率进行Ward聚类分析,利用R语言聚类树的融合水平值定义划分水平,选择具有最大跳跃的分组水平,将中国对虾虾群大致可分为两个组群,河口组和深水组,同时按照各体长组的多度值大小,探讨了各组内具有代表性的分类体长组,结果表明,河口组的中国对虾以体长125—135 mm为主,深水组以体长115—125 mm和105—115mm为主,河口组个体明显大于深水组;河口组分布区入海河流较多,饵料生物丰富,以软泥底质为主,有利于中国对虾的摄食和前期保护,深水组分布于莱州湾中东部,蟹类资源相对较高,且以沙质底质为主,对中国对虾的生长与保护产生一定的影响。     

气候和流域特征变化对淮河流域地表水文过程的影响

定量认识和理解气候与流域特征变化对淮河流域地表水文过程的影响,可以为科学管理淮河流域水资源提供重要的理论参考和技术支撑。评估了多控制因子联立求解归因方法的适用性,以此量化了淮河流域气候和Budyko参数n对不同年代蒸散发(ET)、径流变化(较基准期1961—1980年)的贡献,并且进行了归因分析,结果表明：1)多控制因子联立求解法可以准确有效地分离气候和参数n对ET和径流变化的贡献。2)在气候和参数n变化的共同影响下,20世纪80年代、90年代的ET和径流在沂沭泗河各水文分区均呈减小趋势,而在上游和中游各水文分区的变化则表现出明显的时空差异性。3)就各年代控制ET变化的主要因子,多数水文分区为参数n,其次为降水和潜在蒸散发(PET),分别集中在沂沭泗河地区和淮河上游。20世纪80年代,中游水文分区径流变化的主控因子为PET,其他水文分区则多为降水;而20世纪90年代和21世纪初多数水文分区的主控因子为参数n,其次为降水。总之,控制淮河流域ET和径流变化的物理机制具有明显的空间差异和年代际变化特征。     

Two Magnaporthe appressoria‐specific (MAS) proteins,MoMas3 and MoMas5, are required for suppressing host innate immunity and promoting biotrophic growth in rice cells

In the devastating rice blast fungus Magnaporthe oryzae, six Magnaporthe appressoria‐specific (MAS) proteins are encoded by MoGAS1, MoGAS2 and MoMAS3–MoMAS6. MoGAS1 and MoGAS2 were previously characterized as M. oryzae virulence factors; however, the roles of the other four genes are unknown. Here, we found that, although the loss of any MAS gene did not affect appressorial formation or vegetative growth, ∆Momas3 and ∆Momas5 mutant strains (but not the others) were reduced in virulence on susceptible CO‐39 rice seedlings. Focusing on ∆Momas3 and ∆Momas5 mutant strains, we found that they could penetrate host leaf surfaces and fill the first infected rice cell but did not spread readily to neighbouring cells, suggesting they were impaired for biotrophic growth. Live‐cell imaging of fluorescently labelled MoMas3 and MoMas5 proteins showed that during biotrophy, MoMas3 localized to the apoplastic compartment formed between fungal invasive hyphae and the plant‐derived extra‐invasive hyphal membrane while MoMas5 localized to the appressoria and the penetration peg. The loss of either MoMAS3 or MoMAS5 resulted in the accumulation of reactive oxygen species (ROS) in infected rice cells, resulting in the triggering of plant defences that inhibited mutant growth in planta. ∆Momas3 and ∆Momas5 biotrophic growth could be remediated by inhibiting host NADPH oxidases and suppressing ROS accumulation. Thus, MoMas3 and MoMas5 are novel virulence factors involved in suppressing host plant innate immunity to promote biotrophic growth.     

平滑肌22α蛋白在血管稳态和血管重构中的作用

有关血管稳态和重构的分子机制一直是近年来的研究热点,也被视为治疗血管损伤性疾病的突破点.大量研究证实,血管损伤修复及病理性重构过程与血管平滑肌细胞(vascular smooth muscle cells,VSMCs)的表型转化、异常增殖与迁移、细胞衰老关系密切.平滑肌22α(smooth muscle 22α,SM2...     

B(a)P暴露干扰细胞周期调控蛋白影响孕早期小鼠卵巢黄体功能

该研究旨在探讨苯并(a)芘[Benzo(a)pyrene,B(a)P]对孕早期小鼠卵巢黄体功能的影响及机制.体内模型:将昆明小鼠每晚按雌雄3∶1的比例合笼,次晨查得阴栓记为孕第1天(d1);将其随机分为对照组和B(a)P处理组,每日早晨称重后以0.1 mL/10 g动物体质量灌胃给予0.2 mg/(kg·d)的B(a)...     

若尔盖沙化土地治理土壤微生物群落与功能基因比较研究

【目的】在高寒沙地中建立以赖草和沙生苔草等先锋植物为主的人工草方格,探究其土壤微生物群落动态变化以及养分循环过程。【方法】采用宏基因组测序和qPCR方法进行土壤微生物群落结构组成分析、功能基因注释和绝对丰度测定,并结合土壤理化因子数据进行冗余分析。【结果】人工建立草方格后,沙地土壤中全氮、速效磷以及有机碳含量分别提高了20%-68%、10%-247%、19%-56%;细菌和真菌的群落数量分别提高了17%-81%和2%-95%,与植物促生长相关的鞘氨醇单胞菌属(Sphingomonas)、慢生根瘤菌属(Bradyrhizobium)、硝化螺旋菌属(Nitrospira)、Solirubrobacter属和类诺卡氏菌属(Nocardioides)等细菌种类的相对丰度呈上升趋势;氮循环中与氨氧化和亚硝酸盐氧化相关的amoCAB基因簇和nxrAB基因簇显著富集,发现了完全氨氧化的基因标志。【结论】人工建立草方格有效提升了高寒沙地土壤养分和微生物群落数量,促进了养分循环。适度放牧可以增加沙地生态系统的氮汇扩散性,有助于本土先锋植物定植,为今后在同等高海拔地区采取沙地生态修复措施提供理论参考。