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1.
Hongmei?Luo Yu?Qin Frederic?Reu Sujuan?Ye Yang?Dai Jingcao?Huang Fangfang?Wang Dan?Zhang Ling?Pan Huanling?Zhu Yu?Wu Ting?Niu Zhijian?Xiao Yuhuan?Zheng
Background
Previous research suggested that single gene expression might be correlated with acute myeloid leukemia (AML) survival. Therefore, we conducted a systematical analysis for AML prognostic gene expressions.Methods
We performed a microarray-based analysis for correlations between gene expression and adult AML overall survival (OS) using datasets GSE12417 and GSE8970. Positive findings were validated in an independent cohort of 50 newly diagnosed, non-acute promyelocytic leukemia (APL) AML patients by quantitative RT-PCR and survival analysis.Results
Microarray-based analysis suggested that expression of eight genes was each associated with 1-year and 3-year AML OS in both GSE12417 and GSE8970 datasets (p?<?0.05). Next, we validated our findings in an independent cohort of AML samples collected in our hospital. We found that ubiquitin-conjugating enzyme E2E1 (UBE2E1) expression was adversely correlated with AML survival (p?=?0.04). Multivariable analysis showed that UBE2E1 high patients had a significant shorter OS and shorter progression-free survival after adjusting other known prognostic factors (p?=?0.03). At last, we found that UBE2E1 expression was negatively correlated with patients’ response to induction chemotherapy (p?<?0.05).Conclusions
In summary, we demonstrated that UBE2E1 expression was a novel prognostic factor in adult, non-APL AML patients.2.
Thijs Welle Anna T. Hoekstra Ineke A. J. J. M. Daemen Celia R. Berkers Matheus O. Costa 《Metabolomics : Official journal of the Metabolomic Society》2017,13(7):83
Introduction
Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available.Objective
The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae.Methods
Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes.Results
Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae.Conclusions
The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO.3.
Zhisheng Her Kylie Su Mei Yong Kathirvel Paramasivam Wilson Wei Sheng Tan Xue Ying Chan Sue Yee Tan Min Liu Yong Fan Yeh Ching Linn Kam Man Hui Uttam Surana Qingfeng Chen 《Journal of hematology & oncology》2017,10(1):162
Background
Xenotransplantation of patient-derived AML (acute myeloid leukemia) cells in NOD-scid Il2rγ null (NSG) mice is the method of choice for evaluating this human hematologic malignancy. However, existing models constructed using intravenous injection in adult or newborn NSG mice have inferior engraftment efficiency, poor peripheral blood engraftment, or are difficult to construct.Methods
Here, we describe an improved AML xenograft model where primary human AML cells were injected into NSG newborn pups intrahepatically.Results
Introduction of primary cells from AML patients resulted in high levels of engraftment in peripheral blood, spleen, and bone marrow (BM) of recipient mice. The phenotype of engrafted AML cells remained unaltered during serial transplantation. The mice developed features that are consistent with human AML including spleen enlargement and infiltration of AML cells into multiple organs. Importantly, we demonstrated that although leukemic stem cell activity is enriched and mediated by CD34+CD117+ subpopulation, CD34+CD117? subpopulation can acquire CD34+CD117+ phenotype through de-differentiation. Lastly, we evaluated the therapeutic potential of Sorafenib and Regorafenib in this AML model and found that periphery and spleen AML cells are sensitive to these treatments, whereas BM provides a protective environment to AML.Conclusions
Collectively, our improved model is robust, easy-to-construct, and reliable for pre-clinical AML studies.4.
Introduction
Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages.Objective
To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development.Methods
The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. ‘Nike’) seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with 10?4 and 10?3 M 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4–6-day-old flax seedlings.Results
ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC.Conclusion
Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.5.
Junhong Wei Jinjin Tian Guoqing Pan Jie Xie Jialing Bao Zeyang Zhou 《Biotechnology letters》2017,39(6):857-864
Objective
To develop a reliable and easy to use expression system for antibiotic production improvement of Streptomyces.Results
A two-compound T7 RNA polymerase-dependent gene expression system was developed to fulfill this demand. In this system, the T7 RNA polymerase coding sequence was optimized based on the codon usage of Streptomyces coelicolor. To evaluate the functionality of this system, we constructed an activator gene overexpression strain for enhancement of actinorhodin production. By overexpression of the positive regulator actII-ORF4 with this system, the maximum actinorhodin yield of engineered strain was 15-fold higher and the fermentation time was decreased by 48 h.Conclusion
The modified two-compound T7 expression system improves both antibiotic production and accelerates the fermentation process in Streptomyces. This provides a general and useful strategy for strain improvement of important antibiotic producing Streptomyces strains.6.
7.
Jordan Vacheron Daniel Muller Yvan Moënne-Loccoz Claire Prigent-Combaret 《Plant and Soil》2016,406(1-2):187-199
Aims
The plant-beneficial bacterium Pseudomonas fluorescens F113 harbours an acdS gene, which enables deamination of 1-aminocyclopropane-1-carboxylate. The impact of abiotic and biotic factors on the expression of this gene was assessed, as well as the plant-beneficial properties of F113 under different soil moistures.Methods
An acdS-egfp biosensor was constructed in F113, validated in vitro and used to analyse, by microscopy, its expression on roots of Zea mays comparatively to Beta vulgaris. An acdS mutant was constructed and compared with the wild-type to characterize plant-beneficial effects of F113 on maize lines EP1 and FV2, under well-watered and water deficit conditions.Results
Different patterns of root colonization and acdS expression were observed according to plant genotype. acdS rhizoplane expression was higher on Beta vulgaris, and on maize line FV2 and hybrid PR37Y15 than on maize line EP1 and teosinte. Strain F113 but not its acdS mutant promoted root growth of EP1 under well-watered conditions and germination of FV2 under water deficit conditions.Conclusions
Maize lines differed in their ability to induce acdS expression and to respond to P. fluorescens F113. The maize line leading to higher acdS expression, FV2, was the one benefiting from inoculation under water deficit.8.
Objectives
To develop a versatile Trichoderma reesei (teleomorph Hypocrea jecorina) expression system for the high-purity production of heterologous proteins.Results
The versatile T. reesei expression system is based on xyn1 and xyn2 promoters, A824V transition in XYRI, and a bicomponent carbon source strategy. Red fluorescent protein gene rfp and alkaline endoglucanase EGV gene egv3 from Humicola insolens were used as reporter genes to test our versatile expression systemConclusions
The versatile T. reesei expression system can be applied to produce heterologous proteins with high purity and high yield.9.
10.
Sixuan?Qian Jianyong?Li Ming?Hong Yu?Zhu Huihui?Zhao Yue?Xie Jiayu?Huang Yun?Lian Yanru?Li Shuai?Wang Jianping?Mao Yaoyu?Chen
Background
Cancer cells show increased glycolysis and take advantage of this metabolic pathway to generate ATP. The TP53-induced glycolysis and apoptosis regulator (TIGAR) inhibits aerobic glycolysis and protects tumor cells from intracellular reactive oxygen species (ROS)-associated apoptosis. However, the function of TIGAR in glycolysis and survival of acute myeloid leukemia cells remains unclear.Methods
We analyzed TIGAR expression in cytogenetically normal (CN-) AML patients and the correlations with clinical and biological parameters. In vivo and in vitro, we tested whether glycolysis may induce TIGAR expression and evaluated the combination effect of glycolysis inhibitor and TIGAR knockdown on human leukemia cell proliferation.Results
High TIGAR expression was an independent predictor of poor survival and high incidence of relapse in adult patients with CN-AML. TIGAR also showed high expression in multiple human leukemia cell lines and knockdown of TIGAR activated glycolysis through PFKFB3 upregulation in human leukemia cells. Knockdown of TIGAR inhibited the proliferation of human leukemia cells and sensitized leukemia cells to glycolysis inhibitor both in vitro and in vivo. Furthermore, TIGAR knockdown in combination with glycolysis inhibitor 2-DG led leukemia cells to apoptosis. In addition, the p53 activator Nutlin-3α showed a significant combinational effect with TIGAR knockdown in leukemia cells. However, TIGAR expression and its anti-apoptotic effects were uncoupled from overexpression of exogenous p53 in leukemia cells.Conclusions
TIGAR might be a predictor of poor survival and high incidence of relapse in AML patients, and the combination of TIGAR inhibitors with anti-glycolytic agents may be novel therapies for the future clinical use in AML patients.11.
Andrew T. McKenzie Sarah Moyon Minghui Wang Igor Katsyv Won-Min Song Xianxiao Zhou Eric B. Dammer Duc M. Duong Joshua Aaker Yongzhong Zhao Noam Beckmann Pei Wang Jun Zhu James J. Lah Nicholas T. Seyfried Allan I. Levey Pavel Katsel Vahram Haroutunian Eric E. Schadt Brian Popko Patrizia Casaccia Bin Zhang 《Molecular neurodegeneration》2017,12(1):82
12.
Xiaohong Chen Junjun Chen Yuanxing Zhang Ping Zhu Yong Deng Qin Liu 《Biotechnology letters》2016,38(6):959-967
Objective
To achieve secreted expression of the truncated capsid protein from porcine circovirus type 2 (PCV2) in Pichia pastoris.Results
A truncated cap gene (tcap) with a deleted N-terminal nuclear localization signal was optimized and synthesized. Effective secreted expression was achieved in P. pastoris GS115. The high-productive recombinant strain for tCap was grown in a 5 l bioreactor and the productivity of tCap in supernatant reached 250 μg/ml. Furthermore, serum antibody test demonstrated that adjuvant-assisting tCap induced a significant increase of specific PCV2-Cap antibody over time in mice and a similar antibody level in pigs compared with a commercial Cap-based subunit vaccine.Conclusion
This work establishes a secreted expression strategy in P. pastoris for the production of PCV2 Cap with superior bioactivity, and this strategy might provide potential uses in developing Cap-based subunit vaccine in the future.13.
Elaheh Sajadi Valiollah Babaipour Ali Asghar Deldar Bagher Yakhchali Seyed Safa-Ali Fatemi 《Biotechnology letters》2017,39(9):1395-1401
Objectives
To evaluate the crystallinity index of the cellulose produced by Escherichia coli Nissle 1917 after heterologous expression of the cellulose synthase subunit D (bcsD) gene of Gluconacetobacter xylinus BPR2001.Results
The bcsD gene of G. xylinus BPR2001 was expressed in E. coli and its protein product was visualized using SDS-PAGE. FTIR analysis showed that the crystallinity index of the cellulose produced by the recombinants was 0.84, which is 17% more than that of the wild type strain. The increased crystallinity index was also confirmed by X-ray diffraction analysis. The cellulose content was not changed significantly after over-expressing the bcsD.Conclusion
The bcsD gene can improve the crystalline structure of the bacterial cellulose but there is not any significant difference between the amounts of cellulose produced by the recombinant and wild type E. coli Nissle 1917.14.
15.
Background
Recently, measuring phenotype similarity began to play an important role in disease diagnosis. Researchers have begun to pay attention to develop phenotype similarity measurement. However, existing methods ignore the interactions between phenotype-associated proteins, which may lead to inaccurate phenotype similarity.Results
We proposed a network-based method PhenoNet to calculate the similarity between phenotypes. We localized phenotypes in the network and calculated the similarity between phenotype-associated modules by modeling both the inter- and intra-similarity.Conclusions
PhenoNet was evaluated on two independent evaluation datasets: gene ontology and gene expression data. The result shows that PhenoNet performs better than the state-of-art methods on all evaluation tests.16.
Xiuling Shang Xin Chai Xuemei Lu Yuan Li Yun Zhang Guoqiang Wang Chen Zhang Shuwen Liu Yu Zhang Jiyin Ma Tingyi Wen 《Biotechnology letters》2018,40(2):383-391
Objective
To identify useful native promoters of Corynebacterium glutamicum for fine-tuning of gene expression in metabolic engineering.Results
Sixteen native promoters of C. glutamicum were characterized. These promoters covered a strength range of 31-fold with small increments and exhibited relatively stable activity during the whole growth phase using β-galactosidase as the reporter. The mRNA level and enzymatic activity of the lacZ reporter gene exhibited high correlation (R 2 = 0.96) under the control of these promoters. Sequence analysis found that strong promoters had high similarity of the -10 hexamer to the consensus sequence and preference of the AT-rich UP element upstream the -35 region. To test the utility of the promoter library, the characterized native promoters were applied to modulate the sucCD-encoded succinyl-CoA synthetase expression for l-lysine overproduction.Conclusions
The native promoters with various strengths realize the efficient and precise regulation of gene expression in metabolic engineering of C. glutamicum.17.
Objectives
To clone and express a neopullulanase gene from Lactobacillus mucosae LM1 in Escherichia coli and characterise the resulting recombinant neopullulanase.Results
An ORF in L. mucosae corresponding to a neopullulanase was cloned and expressed in E. coli. The predicted amino acid sequence of the neopullulanase contained catalytic sites and conserved motifs that are present in members of the neopullulanase subfamily. The resulting recombinant neopullulanase was efficiently purified by Ni–NTA affinity chromatography. The purified enzyme optimally hydrolyses pullulan at 37 °C and pH 6.0, producing panose as the major reaction product.Conclusions
To the best of our knowledge, this is the first report of the cloning, expression and characterisation of a neopullulanase gene from a lactic acid bacterium.18.
Objective
To construct a promoter probe vector, pBE-bgaB, to screen strong promoters from Bacillus amyloliquefaciens.Results
266 colonies containing active promoter elements from the genomic DNA of B. amyloliquefaciens were identified. Among these, promoter P41 exhibited the strongest β-Gal activity in Escherichia coli and B. amyloliquefaciens. Sequence analysis showed that promoter P41 contained P ykuN , a ykuN gene encoding flavodoxin. Optimization of the ribosome-binding site from P41 to P382 improved β-Gal activity by ~ 200%.Conclusion
A new strong promoter for protein expression and genetic engineering of Bacillus species.19.