巴西橡胶树乳管细胞HblMYC3互作蛋白筛选与功能分析

MYC是b HLH转录因子家族的亚家族成员,在植物茉莉酸信号转导过程中发挥着重要的调节作用。Hbl MYC3是从巴西橡胶树的乳管细胞中分离鉴定到的MYC类转录因子,其基因表达受割胶和茉莉酸上调。采用酵母双杂交方法初步筛选Hbl MYC3蛋白的互作蛋白,旨在进一步了解Hbl MYC3的功能。结果表明:Hbl MYC1、Hbl MYC2、DNAJ蛋白、谷氧还蛋白2、含A20和AN1锌指结构域的胁迫相关蛋白5、28 ku热和酸稳定的磷蛋白以及25 ku泛素连接酶E2等7种蛋白不同程度地与Hbl MYC3蛋白互作。基于这些互作蛋白的功能,推测Hbl MYC1或Hbl MYC2通过与Hbl MYC3形成二聚体对小橡胶粒子膜蛋白基因表达进行调控,其他蛋白参与胁迫条件下维持二聚体的稳定性和胁迫反应后降解该二聚体。     

An improved method for extraction of sorghum polymeric protein complexes

A method for fractionating sorghum proteins using extraction solvents and techniques designed to obtain polymeric protein structures (especially disulfide linked) was developed. Extraction and separation conditions were optimized in terms of completeness of protein extraction, sample stability, and analytical resolution. After pre-extraction of albumins and globulins, a 3-step sequential procedure involving no reducing agents was applied to ground whole sorghum flour. The three fractions obtained represented proportionally different protein polymer contents and molecular weight distribution as evidenced by comparative size exclusion chromatography. Protein composition also varied among the extracts with differences in kafirin composition and non-kafirin proteins detected in the fractions by RP-HPLC and SDS-PAGE analysis. The ability to quantify and further characterize sorghum polymeric protein complexes will be useful for additional studies linking protein structures with functionality and digestibility and variations for these properties within diverse sorghum germplasm.     

新疆春小麦育成品种耐热性评价

为筛选出耐热性好的小麦种质材料，通过开花期至成熟期人工模拟高温胁迫环境，以千粒重热感指数为主要评价指标，评价了新疆近30年来审定的春小麦品种的相对耐热性，并分析了高温胁迫对小麦籽粒蛋白质、湿面筋含量的影响。结果表明，与自然生长相比，高温胁迫条件下新疆春小麦育成品种的千粒重、籽粒宽度的变化均达到了极显著水平（P<0.01），籽粒长度变化不显著(P>0.05)，不同品种间耐热性存在很大差异。综合三年千粒重热感指数（HSI）分析，耐热性相对较好的品种有17个，连续三年HSI＜1的品种有11个，其中新春37号、新春2号、新春38号在高温胁迫条下千粒重变化较小，产量较稳定，为强耐热品种；对高温敏感品种有26个，连续三年HSI≥1的品种有13个，其中新春13号、新春18号、新春33号耐热性相对较弱。高温胁迫影响小麦籽粒的品质，其中13.95%的品种蛋白质含量降低，6.98%的品种湿面筋含量降低，其他品种高温胁迫后籽粒蛋白质、湿面筋含量均较自然生长有所提高。     

Abnormally modified tau and hypoxic-ischemic brain damage

Tau is the most abundant microtubule-associated protein in the brain. If tau protein lost the normal function, the toxic effect should be showed and plays an important role in various central nervous system lesions. Hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality in the neonatal period and it is mainly characterized by neurological deficits such as cognitive limitations. However, the mechanism still needs further study, and the underlying relationship between tau protein and HIE lacks direct evidence. Some recent clinical study reported that tau protein expression elevated in the serum of asphyxia children and had a high correlation with behavior deficient. In this review, we focus on 3 key points to provide new insights to understand the tau protein-related pathogenesis of HIE as followed: (1) tau protein and its phosphorylation change during central nervous system development; (2) comparison of tau protein expression in developing brain and adult brain under some neurological disorders; (3) potential pathological change of tau in HIE related pathological conditions, such as dysmyelination, inflammation response and glutamate metabolism.     

玉米籽粒早期发育相关蛋白的差异表达特性

玉米籽粒发育早期,代谢活动旺盛,细胞分裂与增大活跃,为后续贮藏物质的合成形成充足库容。为阐明籽粒早期发育的蛋白合成、积累与调控过程,本研究以夏玉米品种登海661为试验材料,在开花期人工饱和授粉后第3、第5、第10天取果穗中部籽粒,利用同位素标记相对定量(iTRAQ)技术分析其蛋白差异表达特性。玉米籽粒早期发育阶段总计鉴定及定量2639种蛋白,这些蛋白涉及多种生物过程与分子功能,其中代谢过程和分子过程是最主要的2个生物过程;催化活性和绑定功能是最主要的2个分子功能,这些生物过程与分子功能对籽粒早期发育具有重要作用。定量分析结果表明137种蛋白在籽粒发育早期显著差异表达,其功能涉及蛋白代谢、胁迫响应、细胞生长与分裂、碳水化合物与能量代谢、转运、次生物质代谢、淀粉合成、转录、油脂代谢、信号转导、氨基酸代谢等。其中,表达差异较大的是与蛋白代谢、胁迫响应、细胞生长与分裂以及碳水化合物与能量代谢相关的蛋白。表达模式聚类结果显示这些不同功能类别的蛋白协同表达,共同调控玉米籽粒的早期发育。     

Mechanism of quercetin improving rat coronary artery myogenic response under high glucose

AIM: To investigate the mechanism of quercetin improving rat coronary artery myogenic response under high glucose (HG) by measuring muscle tension of coronary arterial ring and recording voltage-gated K⁺ channel (Kv) current of coronary artery smooth muscle cells by whole cell patch clamp. METHODS: The coronary rings from the normal SD rats were acutely isolated, and then divided into 6 groups: (1) control group; (2) HG group; (3) HG+low dose (3 μmol/L) of quercetin group; (4) HG+moderate dose (10 μmol/L) of quercetin group; (5) HG+high dose (30 μmol/L) of quercetin group; (6) HG+C6303 (PKC inhibitor)+high dose of quercetin group. Determinations of coronary artery response to vasoconstrictor (60 mmol/L KCl or 0.1 mmol/L U46619) or vasodilator (ACh at 10^-9~10^-5 mol/L) were performed, and the percentage of coronary ring tension was calculated using the contraction as 100% caused by 60 mmol/L KCl. The rat coronary artery smooth muscle cells were acutely isolated for recording the Kv current using whole cell patch clamp. RESULTS: Compared with control group, the contraction amplitudes to 60 mmol/L KCl or 0.1 mmol/L U46619 were significantly increased under HG incubation. Quercetin intervention concentration-dependently reduced the coronary artery contraction amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, the diastolic amplitude to ACh decreased significantly in HG group, and quercetin intervention concentration-dependently increased the coronary artery diastolic amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, HG incubation inhibited Kv current of coronary artery vascular smooth muscle cells significantly, and quercetin intervention attenuated the inhibitory effect of HG on Kv current intensity. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. CONCLUSION: Quercetin has a protective effect on myogenic response of coronary artery under HG and the effects is related to the increase in Kv current and the activation of PKC in vascular smooth muscle cells.     

抗凋亡融合蛋白PTD-Bcl-xL原核表达载体的构建及表达纯化

人工抗凋亡蛋白PTD-Bcl-x L能保护多种因素引起的细胞异常凋亡,为了获得高纯度Bcl-x L与PTD(Protein transduction domains)的融合蛋白,首先采用TRIzol法提取SD大鼠肝脏总RNA,将RNA反转录为c DNA,设计引物以c DNA为模板,PCR扩增Bcl-x L基因,构建p UM19-T-Bcl-x L质粒,并对质粒双酶切鉴定和测序鉴定;其次设计包含PTD序列的Bcl-x L引物,以测序正确的p UM19-T-Bcl-x L质粒为模板,PCR扩增PTD-Bcl-x L序列,将扩增序列克隆入p ET28a载体,构建PTD-Bcl-x L蛋白的原核表达质粒p ET28a-PTD-Bcl-x L,并对p ET28a-PTD-Bcl-x L载体双酶切鉴定和测序鉴定;将p ET28a-PTD-Bcl-x L重组质粒转化大肠杆菌BL21(DE3),用IPTG诱导表达,并对IPTG诱导融合蛋白表达的浓度和诱导时间进行了优化;SDS-PAGE分析表达蛋白的可溶性情况,在变性条件下用Ni-NTA琼脂纯化融合蛋白;最后用SDS-PAGE、Western Blot及质谱对融合蛋白进行鉴定。结果表明:双酶切p UM19-T-Bcl-x L质粒出现约774 bp大小条带,p UM19-T-Bcl-x L质粒测序结果与NCBI数据库比对序列一致,表明成功构建p UM19-T-Bcl-x L质粒;双酶切p ET28a-PTD-Bcl-x L质粒出现约744 bp大小条带,p ET28a-PTD-Bcl-x L质粒测序结果与预期序列一致,表明成功构建了p ET28a-PTD-Bcl-x L原核表达载体;在IPTG诱导下p ET28a-Bcl-x L重组质粒在大肠杆菌BL21(DE3)中表达出36 k Da大小蛋白,最优IPTG诱导浓度为0.1 mmol/L,最佳IPTG诱导时间为6 h;SDS-PAGE电泳显示融合蛋白主要出现在菌液超声后的沉淀里,以包涵体形式表达,经Ni-NTA琼脂纯化获得了高纯度的融合蛋白;Western Blot和质谱鉴定证明IPTG诱导表达蛋白和纯化的融合蛋白为PTD-Bcl-x L蛋白。纯化得到了PTD-Bc L-x L融合蛋白,推进了PTD-Bcl-x L蛋白在猪、牛等家畜精液冷冻保存的应用进程。     

国家奶牛良种补贴项目在泾阳县实施的成效与启示

为今后奶牛改良工作成果的巩固和推广提供依据,对国家奶牛良种补贴项目在泾阳实施的效果与措施进行总结.结果表明:累计使用良种冷冻精液细管23.7万支,生产改良奶牛3.15万头,且已有1.1万头的优质母牛已正式进入产奶阶段.良种补贴后代奶牛的头胎日产奶量达到27 kg左右,比同期母亲日产奶量高2 kg～3 kg;生奶平均乳...     

用酶法制备藏羊血食用蛋白粉的研究

采用四因素三水平正交试验,对藏羊血制备食用蛋白的工艺进行了分析。经分析食用蛋白粉水解最佳条件为：酶解用酶量4.5g,酶解温度为46℃,酶解时间为7.5h,酶解的pH值为10.5,活性炭作用于水解液时由室温升至80℃所需最佳时间为6～8min。     

Interaction of NR2D subunit of NMDA receptor with MOCA

AIM: To identify the potential proteins interacting with NR2D subunit of NMDA receptor by yeast two-hybrid screening and to investigate the role of NR2D in excitotoxicity of the retina.METHODS: The Clontech GAL4 yeast two-hybrid system was used to screen the mouse brain cDNA library, and the bait plasmid containing C-terminus of NR2D was constructed. Physical interaction between 2 proteins was verified by co-immunoprecipitation assay. The subcellular localization of 2 proteins in the mouse retina was observed under microscope with immunofluorescence.RESULTS: Modifier of cell adhesion (MOCA) was identified as a new protein interacting with NR2D. MOCA and NR2D were co-expressed in the mouse retina. CONCLUSION: MOCA specifically interacts with NR2D, which provides the experimental basis for identifying the role of glutamate excitotoxicity in the retina neurodegeneration.