玉米热激蛋白ZmHSP70-12基因的克隆及表达分析

热激蛋白70(HSP70)是原核和真核细胞中普遍存在的一种高度保守的分子伴侣。从玉米中克隆1个HSP70家族成员。该基因cDNA序列全长为1 992 bp,开放阅读框为2 352 bp,编码663个氨基酸,蛋白质分子量约75.0 kD。蛋白结构预测及同源比对分析表明,该基因编码蛋白含ATPase位点和HSP70保守结构域,与拟南芥AtHSP70-12序列高度相似,命名为ZmHSP70-12。蛋白亚细胞定位显示,ZmHSP70-12蛋白在内质网中表达。实时荧光定量PCR分析表明,ZmHSP70-12对非生物胁迫高温、干旱均具有明显的应答反应,推测ZmHSP70-12是玉米中与胁迫逆境相关的基因。     

盐胁迫下外源功能微生物调控水稻生长特征研究

以高产水稻品种中浙优1号为材料,设置2个盐胁迫处理(S0,正常生长条件;S1,盐逆境,3g NaCl/kg干土)和2个微生物处理(M0,对照;MM,荧光假单胞菌与巴西固氮螺菌共同接种水稻根际环境),研究了盐胁迫下外源功能微生物对水稻生长特征的影响。结果表明,与S0处理相比,S1处理下水稻植株生育期严重滞后,干物质积累量以及产量构成因子显著降低;与S1M0处理相比,S1MM处理可显著提高水稻剑叶光合速率、地上部干物质量以及产量构成因子。可见,荧光假单胞菌与巴西固氮螺菌进入稻田土壤可缓解盐逆境对水稻生长的抑制作用,提升水稻叶片光合能力、耐盐性能,并显著提高水稻分蘖能力和结实率,增加千粒重,进而增加水稻产量。     

外源亚精胺对盐胁迫下甜菜生长及养分吸收的影响

为了探究外源亚精胺是否具有缓解甜菜盐害作用,采用霍兰营养液室内水培方法,测定了280mmol/L NaCl胁迫条件下,喷施0.25 mmol/L外源亚精胺后,耐盐‘T510’和盐敏感‘210’甜菜品系幼苗生长、生理及其体内N、P、K养分含量的变化情况。结果发现,盐胁迫下(Na处理),除MDA和P素含量升高外,两品系甜菜幼苗的叶片相对含水量、叶面积、叶绿素含量、幼苗生物量及N、K养分含量指标均明显降低;与Na处理比,喷施亚精胺的盐胁迫处理,除MDA和P素含量降低外,其它指标明显增加,两品系甜菜幼苗生长和养分吸收状况明显改善;外源亚精胺对耐盐‘T510’品系的调节作用大于‘210’品系。因此外源亚精胺能有效缓解盐胁迫对甜菜生长的伤害,对耐盐品系的调节效果更佳。     

Role of chlorogenic acid in endothelial dysfunction in db/db mice

AIM: To explore the effects of chlorogenic acid (CGA) on endothelial dysfunction in db/db mice and the possible mechanism. METHODS: Male db/db mice (n=12) were divided into control group and CGA group, with 6 mice in each group. The mice in CGA group were treated with diet containing 0.02% CGA, while the mice in control group were given normal diet only. The observation period was 12 weeks. Fasting blood glucose level, tail blood pressure and the body weight were analyzed each week. At the end of the 12th week, the mice were anesthetized and blood was taken from carotid artery. The plasma levels of heme oxygenase-1 (HO-1), catalase (CAT), NAD(P)H dehydrogenase quinone 1 (NQO1) and glutathione peroxidase-1 (GPx-1) were measured by ELISA. The mouse aortas were isolated, and the superoxide anion and nitric oxide (NO) levels were measured by DHE and DAF-2 DA staining, respectively. Wire Myograph System was used to detect the vasorelaxation of db/db mouse aorta. The protein levels of peroxisome proliferator-activated receptor α (PPARα), nuclear factor E2-related factor 2 (Nrf2), phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated endothelial NO synthase (p-eNOS), P22^phox and P47^phox were determined by Western blot. RESULTS: Dietary CGA decreased fasting blood glucose and body weight in db/db mice as compared with control group (P<0.01 or P<0.05). The plasma levels of HO-1, CAT, NQO1 and GPx-1 in CGA group were higher than those in control group (P<0.01 or P<0.05). Administration of CGA for 12 weeks attenuated superoxide anion level, increased NO level in the mouse endothelium and improved endothelium-dependent relaxation of the db/db mouse aorta. CGA also increased the protein levels of PPARα, Nrf2, p-AMPK and p-eNOS, and decreased P22^phox and P47^phox levels (P<0.01). CONCLUSION: Dietary CGA improves db/db mouse endothelium-dependent relaxation. This effect may be related to the increases in the levels of antioxidant molecules PPARα, Nrf2 and p-AMPK, and the up-regulation of antioxidant capacity, thus decreasing the oxidative stress, promoting eNOS phosphorylation, and increasing NO level.     

大豆PHD家族蛋白的全基因组鉴定及表达特征分析

PHD（Plant Homeodomain Finger）基因家族编码一类锌指转录因子,广泛参与植物的生长发育和逆境应答过程。通过全基因组鉴定获得了95个大豆PHD家族蛋白。通过共线性分析、进化树构建、基因结构和功能结构域鉴定、GO注释分析、不同组织间和非生物胁迫下表达分析等,获得了大豆PHD家族基因复制、家族进化、保守结构域及基因表达等信息。结果表明,大豆PHD基因在家族进化、基因结构和保守结构域上存在较大变异,可能参与Zn ²⁺结合、DNA结合及表观遗传调控等分子过程,参与调控植物生长发育和逆境应答。这些结果为进一步研究大豆PHD家族在生长发育和逆境应答中的生物学功能提供重要线索。     

NRF2 attenuates oxidative stress and lysosomal dysfunction in doxorubicin-induced H9C2 cells

AIM:To study the effect of nuclear factor E2-related factor 2 (NRF2) on oxidative stress injury and lysosomal dysfunction in doxorubicin (DOX)-induced rat myocardial H9C2 cells. METHODS:The H9C2 cells were treated with DOX. The expression of NRF2 at mRNA and protein levels was determined by real-time PCR and Western blot. The H9C2 cells stably over-expressing NRF2 were established by lentiviral infection. Real-time PCR and Western blot were used to identify the efficiency of over-expression. After DOX treatment, the cell viability was measured by CCK-8 assay, the activity of lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), and the content of malondialdehyde (MDA) in the cell supernatant were detected. FITC-dextran was used to analyze lysosomal pH, and the protein expression of lysosomal-associated membrane protein 1 (LAMP1) and cathepsin B was determined by Western blot.RESULTS:The expression of NRF2 at mRNA and protein levels in DOX-treated H9C2 cells was significantly decreased (P<0.05). Over-expression of NRF2 significantly up-regulated the mRNA and protein expression of NRF2 in DOX-treated H9C2 cells (P<0.05). After DOX treatment, the cell viability was decreased, and LDH activity was increased. The activity of SOD, GSH-Px and CAT was decreased, and the content of MDA was increased (P<0.05). The lysosomal pH was increased, and the protein expression of LAMP1 and cathepsin B decreased (P<0.05). Over-expression of NRF2 increased the cell viability, decreased LDH activity, increased the activity of SOD, GSH-Px and CAT, and decreased the content of MDA in cell supernatant (P<0.05). Over-expression of NRF2 also decreased the lysosomal pH, and increased the protein expression of LAMP1 and cathepsin B (P<0.05). CONCLUSION:DOX inhibits the expression of NRF2 in the myocardial H9C2 cells. Over-expression of NRF2 attenuates oxidative stress and lysosomal dysfunction in the H9C2 cells induced by DOX.     

盐胁迫对膜荚黄芪种子萌发的影响

为了保护并开发膜荚黄芪,同时改良盐碱地,研究了3种不同盐（中性盐NaCl、碱性盐Na₂CO₃和复盐）对膜荚黄芪种子发芽率、发芽势、抗氧化酶活性、丙二醛含量、可溶性蛋白质含量和相对电导率的影响。结果表明,不同盐胁迫对膜荚黄芪种子的影响不同,随着盐浓度的增加,黄芪种子的发芽率和发芽势逐渐降低;低浓度的NaCl和复盐可提高抗氧化酶活性,Na₂CO₃处理随着其浓度增加对抗氧化酶活性的抑制作用增强;各处理均增大了丙二醛含量和相对电导率;NaCl和复盐处理降低了膜荚黄芪种子可溶性蛋白含量,Na₂CO₃处理的可溶性蛋白含量随盐浓度增加而增加,综合各项指标可得同等盐浓度条件下胁迫作用由强到弱为Na₂CO₃>NaCl>复盐。     

外源褪黑素和脱落酸对干旱胁迫下葡萄生理特性的影响

为了探讨褪黑素(MT)和脱落酸(ABA)两者混合施用对植物响应干旱胁迫的综合效应,以盆栽‘阳光玫瑰’葡萄为材料,通过根灌100μmol·L~(-1)的MT溶液和叶面喷施50μmol·L~(-1)的ABA溶液及二者组合处理,研究MT和ABA对干旱胁迫下葡萄生理特性的影响。结果表明,与干旱对照组(D_(ck))相比,MT处理导致葡萄叶片MDA、H_2O_2含量和相对电导率分别降低了14.42%、44.11%和21.26%,叶片相对含水量提高了1.12%,同时SOD和POD酶活性分别提高了14.00%和3.01%。这些均表明MT处理有效缓解了干旱胁迫对植株造成的损伤。50μmol·L~(-1 )的ABA处理组叶片MDA含量和相对电导率较干旱对照组提高了9.43%和17.25%,表明ABA处理没有缓解植株的胁迫状态。MT和ABA组合处理具有和MT处理类似的效果。结果表明,褪黑素可以通过减轻膜脂过氧化程度,增强抗氧化系统能力,从而缓解干旱胁迫对葡萄的氧化损伤,提高抗旱性;同时削弱ABA带来的负面效应。     

水分优化对温室葡萄产量及土壤生物学特性的影响

为揭示滴灌不同水分调控下设施栽培葡萄产量与土壤学特性等相关指标的响应关系,在甘肃省永登县设施葡萄试验基地开展葡萄滴灌不同生育期水分调控田间灌溉试验,分析水分调控对设施栽培葡萄土壤积温、蔗糖酶和淀粉酶活性、有机碳(TOC)、微生物量碳(MBC)和微生物熵(qMB)等土壤学特性的影响,基于隶属函数综合分析明确影响葡萄产量及各项土壤生物学特性指标的最佳水分优化处理。结果表明:新梢期水分胁迫的土壤积温、土壤酶、TOC、MBC、qMB均显著(P <0. 05)高于对照;新梢期水分胁迫较对照可增产44. 6%;果实膨大期作为葡萄生长的关键阶段,此时水分胁迫对土壤淀粉酶影响不显著,但对其他土壤学特性指标具有一定的抑制作用,并且可减产9.7%;隶属函数综合分析表明,土壤生物学特性指标及产量综合隶属排名为:PS﹥FS﹥CS﹥CK﹥ES。