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971.
Deyao Du Yu Zhu Junhong Wei Yuqing Tian Guoqing Niu Huarong Tan 《Applied microbiology and biotechnology》2013,97(14):6383-6396
Nikkomycins and gougerotin are peptidyl nucleoside antibiotics with broad biological activities. The nikkomycin biosynthetic gene cluster comprises one pathway-specific regulatory gene (sanG) and 21 structural genes, whereas the gene cluster for gougerotin biosynthesis includes one putative regulatory gene, one major facilitator superfamily transporter gene, and 13 structural genes. In the present study, we introduced sanG driven by six different promoters into Streptomyces ansochromogenes TH322. Nikkomycin production was increased significantly with the highest increase in engineered strain harboring hrdB promoter-driven sanG. In the meantime, we replaced the native promoter of key structural genes in the gougerotin (gou) gene cluster with the hrdB promoters. The heterologous producer Streptomyces coelicolor M1146 harboring the modified gene cluster produced gougerotin up to 10-fold more than strains carrying the unmodified cluster. Therefore, genetic manipulations of genes involved in antibiotics biosynthesis with the constitutive hrdB promoter present a robust, easy-to-use system generally useful for the improvement of antibiotics production in Streptomyces. 相似文献
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973.
Chia-Hao Chin Shu-Hwa Chen Chun-Yu Chen Chao A. Hsiung Chin-Wen Ho Ming-Tat Ko Chung-Yen Lin 《Gene》2013
As is generally assumed, clusters in protein–protein interaction (PPI) networks perform specific, crucial functions in biological systems. Various network community detection methods have been developed to exploit PPI networks in order to identify protein complexes and functional modules. Due to the potential role of various regulatory modes in biological networks, a single method may just apply a single graph property and neglect communities highlighted by other network properties. 相似文献
974.
X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder resulting from mutations within the ABCD1 gene. Adrenomyeloneuropathy (AMN) and childhood cerebral ALD (CCALD) are most common phenotypes in the Western ALD patients. Here we performed mutation analysis of ABCD1 in 10 Chinese ALD families and identified 8 mutations, including one novel deletion (c.1477_1488 + 11del23) and 7 known mutations. Mutations c.1772G>A and c.1816T>C were first reported in the Chinese patients. Mutations c.1661G>A and c.1679C>T were demonstrated to be de novo mutations. The dinucleotide deletion 1415_16delAG, described as a mutational hotspot in different ethnic groups, was identified in two families. In addition, we performed a retrospective nation-wide mutation study of X-linked ALD in China based on a literature review. The retrospective study further confirmed the hypothesis that exon 6 is a potential mutation cluster region in the Asian populations. Furthermore, it suggested that CCALD is the most common phenotype in China. 相似文献
975.
Rong Wang Hui Gao Wei Xu Hui Li Yiqing Mao Yi Wang Tingting Guo Xi Wang Rongjing Song Zhixin Li David M. Irwin Gang Niu Huanran Tan 《Gene》2013
To investigate the role of liver-specific expression of glucokinase (GCK) in the pathogenesis of hyperglycemia and to identify candidate genes involved in mechanisms of the onset and progression of maturity onset diabetes of the young, type 2 (MODY-2), we examined changes in biochemical parameters and gene expression in GCK knockout (gckw/–) and wild-type (gckw/w) mice as they aged. Fasting blood glucose levels were found to be significantly higher in the gckw/– mice, compared to age-matched gckw/w mice, at all ages (P < 0.05), except at 2 weeks. GCK activity of gckw/– mice was about 50% of that of wild type (gckw/w) mice (P < 0.05). Glycogen content at 4 and 40 weeks of age was lower in gckw/– mice compared to gckw/w mice. Differentially expressed genes in the livers of 2 and 26 week-old liver-specific GCK knockout (gckw/–) mice were identified by suppression subtractive hybridization (SSH), which resulted in the identification of phosphoenolpyruvatecarboxykinase (PEPCK, also called PCK1) and Sterol O-acyltransferase 2 (SOAT2) as candidate genes involved in pathogenesis. The expressions of PEPCK and SOAT2 along with glycogen phosphorylase (GP) and glycogen synthase (GS) were then examined in GCK knockout (gckw/–) and wild-type (gckw/w) mice at different ages. Changes in PEPCK mRNA levels were confirmed by real-time RT-PCR, while no differences in the levels of expression of SOAT2 or GS were observed in age-matched GCK knockout (gckw/–) and wild-type (gckw/w) mice. GP mRNA levels were decreased in 40-week old gckw/– mice compared to age-matched gckw/w mice. Changes in gluconeogenesis, delayed development of GCK and impaired hepatic glycogen synthesis in the liver potentially lead to the onset and progression of MODY2. 相似文献
976.
Fei Ge Ping Zhang Junwei Niu Xiaohang Pei Cheng Lian Runhong Yu Rongjun Ma Yin Zhang Zunmin Zhu Kai Sun 《Journal of cellular physiology》2020,235(4):3790-3797
Acute myelocytic leukemia (AML) is an aggressive malignant tumor and typically fatal without treatment. Identification and development of novel biomarkers could be beneficial for the diagnosis and prognosis of AML patients. Here, we aimed to identify the accurate DNA methylation prognostic signatures for AML patients. The DNA methylation data of AML patients and corresponding clinical information were retrieved from The Cancer Genome Atlas database. CPG sites that correlates closely with the survival of the AML patients were identified and further combined into CPG sites pairs to screen the survival-related pairs. The prognostic signatures were identified by the C-index and forward search algorithms and validated by the verification group. Finally, the functional enrichment analysis was performed on these CPG sites. As a result, a total of 498 CPG sites associated with the overall survival of AML patients was obtained. A prognostic signature composed of 10 CPG sites pairs was obtained and validated. The functional enrichment analysis showed prognostic genes were mainly enriched in tumor protein processing, cell differentiation, blood leukocyte immunity, and platelet growth factor pathways. In summary, we identified two accurate prognostic methylation signatures (NDRG2 and TLR7), which would be served as a novel therapy target for AML. 相似文献
977.
Lele Niu Yuanbo Jia Mian Wu Han Liu Yanjing Feng Yan Hu Xiaohui Zhang Dengfeng Gao Feng Xu Guoyou Huang 《Journal of cellular physiology》2020,235(11):8345-8357
Cardiac fibrosis is a common pathway leading to heart failure and involves continued activation of cardiac fibroblasts (CFs) into myofibroblasts during myocardium damage, causing excessive deposition of the extracellular matrix (ECM) and thus increases matrix stiffness. Increasing evidence has shown that stiffened matrix plays an important role in promoting CF activation and cardiac fibrosis, and several signaling factors mediating CF mechanotransduction have been identified. However, the key molecules that perceive matrix stiffness to regulate CF activation remain to be further explored. Here, we detected significantly increased expression and nuclear localization of Yes-associated protein (YAP) in native fibrotic cardiac tissues. By using mechanically regulated in vitro cell culture models, we found that a stiff matrix-induced high expression and nuclear localization of YAP in CFs, accompanied by enhanced cell activation. We also demonstrated that YAP knockdown decreased fibrogenic response of CFs and that YAP overexpression promoted CF activation, indicating that YAP plays an important role in mediating matrix stiffness-induced CF activation. Further mechanistic studies revealed that the YAP pathway is an important signaling branch downstream of angiotensin II type 1 receptor in CF mechanotransduction. The findings help elucidate the mechanism of fibrotic mechanotransduction and may contribute to the development of new approaches for treating fibrotic diseases. 相似文献
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