Shorter GT repeat polymorphism in the heme oxygenase-1 gene promoter has protective effect on ischemic stroke in dyslipidemia patients

Background  

The microsatellite polymorphism of heme oxygenase (HO)-1 gene promoter has been shown to be associated with the susceptibility to ischemic event, including coronary artery disease (CAD), myocardial infarction, and peripheral vascular disease. We aimed to examine whether the length of (GT)_n repeats in HO-1 gene promoter is associated with ischemic stroke in people with CAD risk factors, especially low level of HDL.     

The functional expression of calcium-sensing receptor in the differentiated THP-1 cells

The expression and function of calcium-sensing receptor (CaSR) in differentiated THP-1 (human acute monocytic leukemia cell line) cells are unknown currently. This study investigated above-mentioned issues using TRAP staining, immunofluorescence staining, Western blotting, ELISA, and Laser Confocal Scanning Microscopy techniques. We found that CaSR protein was expressed, and mainly located in the membrane and cytoplasm in differentiated THP-1 cells. Elevated extracellular calcium or GdCl₃ (an agonist of CaSR) raised intracellular calcium concentration. And this increase was inhibited or abolished by NPS2390 (an inhibitor of CaSR), U73122 (a specific inhibitor of phospholipase C, PLC) or thapsigargin (a Ca²⁺-ATPase inhibitor). The extracellular GdCl₃ elevation stimulated both of IL-1β and TNFα release, and this effect of GdCl₃ was inhibited by NPS2390. In conclusion, CaSR is functionally expressed in differentiated THP-1 cells, and the activated CaSR contributes to intracellular calcium increment through Gq-PLC- inositol triphosphate (IP3) pathway and commits to cytokine secretion. These results suggest that CaSR might be involved in a variety of pathological processes mediated by activated monocyte-macrophages.     

不同pH调节剂对产琥珀酸放线杆菌NJ113发酵产丁二酸的影响

在3L发酵罐中分别采用不同的碱性物质作为pH调节剂,考察其对产琥珀酸放线杆菌Actinobacillus succinogenes NJ113厌氧发酵制备丁二酸的影响。结果表明:Ca2+、NH4+调节剂对菌体生长代谢有较大阻碍作用,丁二酸产量较低;采用含Na+调节剂,在发酵中后期菌体出现絮凝现象严重,且产丁二酸能力骤降;采用含Mg2+调节剂,整个发酵过程菌体代谢旺盛,发酵效果较佳。根据各碱性物质的调节能力以及对菌体生长代谢的影响,选择NaOH、Mg(OH)2和Na2CO3、Mg(OH)2分别作为混合碱组分调节pH,并对两组混合碱中各物质的质量比例进行优化。结果表明,以NaOH、Mg(OH)2混合,两者质量比为1:1时,发酵效果最好,丁二酸质量浓度高达到69.8g/L,质量收率74.5%。该种混合碱配比可有效替代碱式MgCO3调节pH,既达到高产丁二酸的目的,又可降低生物制备丁二酸的成本。     

长白山阔叶红松林乔木树种幼苗组成及其年际动态

为了解阔叶红松(Pinus koraiensis)林乔木树种幼苗的组成及其年际动态, 以长白山阔叶红松林25 ha动态监测样地为平台, 在样地内150个种子收集器周围设置了600个5 m×5 m幼苗样方。基于2006–2008年连续3年的幼苗样方调查数据, 对乔木幼苗的树种组成、数量组成、空间分布特征、年际动态、新增和死亡幼苗组成等进行了分析。结果表明: (1)从树种组成来看, 该群落乔木树种的幼苗组成种类较为丰富, 共记录到21个树种, 这些树种也是样地内胸径1 cm以上乔木树种的主要组成成分。树种组成在年际间变化不大, 但各样方间表现出极大的空间变异。(2)从数量组成来看, 共记录到11,959株乔木幼苗, 以水曲柳(Fraxinus mandshurica)和紫椴(Tilia amurensis)幼苗数最多, 占总幼苗数的72.75%; 水曲柳、紫椴和红松的幼苗数量在年际间有明显波动, 其他树种年际间波动较小。(3)从新增和死亡幼苗的数量与组成来看, 共记录到15个乔木树种的新增幼苗, 其中紫椴、水曲柳、色木槭(Acer mono)、红松等10个树种在每次调查中都有新苗记录, 新苗数量在年际间随物种和样方位置表现出明显差异。(4)对各树种的幼苗、种子和大树的组成和空间分布的比较发现, 各树种的幼苗、种子和大树之间的数量组成和比例差异较大, 其中紫椴、水曲柳、色木槭和假色槭(A. pseudo-sieboldianum)的幼苗、种子在整个样地内都有分布, 春榆(Ulmus japonica)和怀槐(Maackia amurensis)幼苗的空间分布与种子和大树不一致, 糠椴(T. mandshurica)和山丁子(Malus baccata)等的幼苗、种子和大树的个体数相对都较少, 且它们的分布是一致的。     

Pea powdery mildew <Emphasis Type="Italic">er1</Emphasis> resistance is associated to loss-of-function mutations at a <Emphasis Type="Italic">MLO</Emphasis> homologous locus

The powdery mildew disease affects several crop species and is also one of the major threats for pea (Pisum sativum L.) cultivation all over the world. The recessive gene er1, first described over 60 years ago, is well known in pea breeding, as it still maintains its efficiency as a powdery mildew resistance source. Genetic and phytopathological features of er1 resistance are similar to those of barley, Arabidopsis, and tomato mlo powdery mildew resistance, which is caused by the loss of function of specific members of the MLO gene family. Here, we describe the obtainment of a novel er1 resistant line by experimental mutagenesis with the alkylating agent diethyl sulfate. This line was found to carry a single nucleotide polymorphism in the PsMLO1 gene sequence, predicted to result in premature termination of translation and a non-functional protein. A cleaved amplified polymorphic sequence (CAPS) marker was developed on the mutation site and shown to be fully co-segregating with resistance in F₂ individuals. Sequencing of PsMLO1 from three powdery mildew resistant cultivars also revealed the presence of loss-of-function mutations. Taken together, results reported in this study strongly indicate the identity between er1 and mlo resistances and are expected to be of great breeding importance for the development of resistant cultivars via marker-assisted selection.     

Floral-dip法大豆GmDREB转录因子转拟南芥研究

DREB（dehydration responsive element binding）转录因子通过调控下游多个抗逆相关基因的表达,能有效提高植物的抗逆性。将构建的植物高效表达载体GmDREB：：pCAMBIA1304,借助优化的floral-dip法,转入模式植物拟南芥,并经潮霉素Hygromycine（40-50mg&#183;L^-1）抗性筛选得到22棵抗性植株。对抗性植株再进行PCR和GUS检测获得19颗阳性苗,阳性率为86．3％。对T1代种子进行抗性分离比例统计,有4个株系的分离比例接近3：1,符合孟德尔遗传定律,说明外源基因GmDREB在这些株系的染色体中可能是单拷贝插入。继续对上述4个株系的后代进行抗性筛选．现已得到2个纯合的转基因株系。导入的报告基因GUS组织染色检测表明,转入大豆DREB基因在拟南芥的根系和子叶中均有大量表达,并在叶脉中表达。     

Genetic evidence for functional dependency of p18Ink4c on Cdk4

The INK4 family of cyclin-dependent kinase (CDK) inhibitors negatively regulates cyclin D-dependent CDK4 and CDK6 and induces the growth-suppressive function of Rb family proteins. Mutations in the Cdk4 gene conferring INK4 resistance are associated with familial and sporadic melanoma in humans and result in a wide spectrum of tumors in mice, suggesting that INK4 is a major regulator of CDK4. Mice lacking the Cdk4 gene exhibit various defects in many organs associated with hypocellularity, whereas loss of the p18(Ink4c) gene results in widespread hyperplasia and organomegaly. To genetically test the notion that the function of INK4 is dependent on CDK4, we generated p18; Cdk4 double-mutant mice and examined the organs and tissues which developed abnormalities when either gene is deleted. We show here that, in all organs we have examined, including pituitary, testis, pancreas, kidney, and adrenal gland, hyperproliferative phenotypes associated with p18 loss were canceled. The double-mutant mice exhibited phenotypes very close to or indistinguishable from that of Cdk4 single-mutant mice. Mice lacking p27(Kip1) develop widespread hyperplasia and organomegaly similar to those developed by p18-deficient mice. The p27; Cdk4 double-mutant mice, however, displayed phenotypes intermediate between those of p27 and Cdk4 single-mutant mice. These results provide genetic evidence that in mice p18(Ink4c) and p27(Kip1) mediate the transduction of different cell growth and proliferation signals to CDK4 and that p18(Ink4c) is functionally dependent on CDK4.     

Therapeutic effect of anthracene-based anticancer agent ethonafide in an animal model of multiple sclerosis

The side effects of cancer chemotherapeutic agents such as mitoxantrone (MIT) in multiple sclerosis (MS) patients justify the search for less toxic drugs. Ethonafide is an anthracene-based antineoplastic drug similar to MIT. With reference to MIT, we examined the effect of ethonafide on experimental autoimmune encephalomyelitis (EAE) in C57BL/6 mice, an animal model of human MS. We demonstrated that ethonafide is effective in preventing development of EAE as well as in ameliorating the severity of EAE when disease is ongoing. In relatively higher dosages, the effects of ethonafide and MIT on EAE were identical, whereas in lower dosages, MIT seemed more effective. Therapeutic effects of ethonafide were associated with the initial reduction in cellular counts of CD3(+), CD4(+), CD8(+), B220(+), CD11b(+), NK cells, and NKT cells, followed by recovery of these cells from the bone marrow. Interestingly, the recovered autoreactive T cells in ethonafide-treated animals have reduced capacity to expand and produce cytokines in response to myelin Ag stimulation. Furthermore, CD4(+)CD25(+) regulatory T cells were relatively resistant to depletion and/or recovered faster than T effector cells. The ability of regulatory T cells to resist depletion and replenish quickly during cell ablation therapy may provide an opportunity to reprogram the immune system. Moreover, we provided evidences that ethonafide has less cardiac toxicity compared with MIT. The effectiveness and the low cardiotoxicity of ethonafide might make it a promising immunosuppressive agent for clinical use in treating MS patients.     

Yeast two hybrid analyses reveal novel binary interactions between human cytomegalovirus-encoded virion proteins

Human cytomegalovirus (HCMV) is the largest human herpesvirus and its virion contains many viral encoded proteins found in the capsid, tegument, and envelope. In this study, we carried out a yeast two-hybrid (YTH) analysis to study potential binary interactions among 56 HCMV-encoded virion proteins. We have tested more than 3,500 pairwise combinations for binary interactions in the YTH analysis, and identified 79 potential interactions that involve 37 proteins. Forty five of the 79 interactions were also identified in human cells expressing the viral proteins by co-immunoprecipitation (co-IP) experiments. To our knowledge, 58 of the 79 interactions revealed by YTH analysis, including those 24 that were also identified in co-IP experiments, have not been reported before. Novel potential interactions were found between viral capsid proteins and tegument proteins, between tegument proteins, between tegument proteins and envelope proteins, and between envelope proteins. Furthermore, both the YTH and co-IP experiments have identified 9, 7, and 5 interactions that were involved with UL25, UL24, and UL89, respectively, suggesting that these "hub" proteins may function as the organizing centers for connecting multiple virion proteins in the mature virion and for recruiting other virion proteins during virion maturation and assembly. Our study provides a framework to study potential interactions between HCMV proteins and investigate the roles of protein-protein interactions in HCMV virion formation or maturation process.