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101.
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103.
Xiao-Long Lin Yan-Min Zhao Li-Ping Yan Wen-Bin Liu Wen-Jun Bu Xin-Hua Wang Chen-Guang Zheng 《Zoologica scripta》2022,51(1):119-132
Evolutionary analysis of Prodiamesinae has long been impeded by lack of information, and its phylogenetic relationship with Orthocladiinae remains questionable. Here, ten complete mitochondrial genomes (mitogenomes) of Orthocladiinae sensu lato were newly sequenced, including three Prodiamesinae species and seven Orthocladiinae species. Coupled with published mitogenomes, a total of 12 mitogenomes of Orthocladiinae sensu lato were selected for a comparative mitogenomic analysis and phylogenetic reconstruction. Mitogenomes of Orthocladiinae sensu lato are conserved in structure, and all genes arrange the same gene order as the ancestral insect mitogenome. Nucleotide composition is highly biased, and the control region displayed the highest A + T content. All protein-coding genes are under purifying selection, and the ATP8 evolves at the fastest rate. In addition, the mitogenomes of Orthocladiinae sensu lato are highly conserved, and they are practically useful for phylogenetic inference, suggesting a re-classification of Orthocladiinae by sinking Prodiamesinae as a subgroup of Orthocladiinae. 相似文献
104.
Photosynthesis-irradiance (PI) curves are extensively used in field and laboratory research to evaluate the photon-use efficiency of plants. However, most existing models for PI curves focus on the relationship between the photosynthetic rate (Pn) and photosynthetically active radiation (PAR), and do not take account of the influence of environmental factors on the curve. In the present study, we used a new non-competitive inhibited Michaelis-Menten model (NIMM) to predict the co-variation of Pn, PAR, and the relative pollution index (I). We then evaluated the model with published data and our own experimental data. The results indicate that the Pn of plants decreased with increasing I in the environment and, as predicted, were all fitted well by the NIMM model. Therefore, our model provides a robust basis to evaluate and understand the influence of environmental pollution on plant photosynthesis. 相似文献
105.
Lishan Zhang Ming Liu Jinglei Liu Xingkai Li Ming Yang Benhua Su Yanliang Lin 《Journal of cellular physiology》2019,234(8):12692-12700
27-Hydroxycholesterol (27-HC) has been implicated in the pathological process of estrogen receptor positive breast cancer. However, the role of 27-HC in lung adenocarcinoma is still unclear. Because bone metastasis is a main reason for the high mortality of lung adenocarcinoma, this study aimed to investigate the effect of 27-HC on osteoclastogenesis in lung adenocarcinoma microenvironment. The results showed that the conditioned media (CM) from lung adenocarcinoma cells cocultured with macrophages promoted osteoclast differentiation, which was enhanced by 27-HC. Further investigation showed that CM inhibited miR-139 expression and promoted c-Fos expression. Luciferase reporter assay identified c-Fos as a direct target of miR-139. CM also induced the expression and nuclear translocation of NFATc1 and STAT3 phosphorylation, which was enlarged by 27-HC but was attenuated by miR-139. Coimmunoprecipitation assay demonstrated that 27-HC increased the interaction between NFATc1 and phosphorylated STAT3, which was restricted by miR-139. Chromatin immunoprecipitation assay showed that pSTAT3 could bind to the promoter of c-Fos, c-Fos could bind to the promoter of NFATc1, and both pSTAT3 and NFATc1 could bind to the promoter of Oscar, which were enlarged by 27-HC but were blocked by miR-139. Knockdown of c-Fos mimicked the effect of miR-139. These results suggested that CM, especially containing 27-HC, promoted osteoclastogenesis by inhibiting miR-139 expression and activating the STAT3/c-Fos/NFATc1 pathway. 相似文献
106.
Wei Guo Qiulan Huang Yuhui Feng Taicong Tan Suhao Niu Shaoli Hou Zhigang Chen Zhi-Qiang Du Yu Shen Xu Fang 《Biotechnology and bioengineering》2020,117(8):2410-2419
Metabolic engineering of Saccharomyces cerevisiae for high-level production of aromatic chemicals has received increasing attention in recent years. Tyrosol production from glucose by S. cerevisiae is considered an environmentally sustainable and safe approach. However, the production of tyrosol and salidroside by engineered S. cerevisiae has been reported to be lower than 2 g/L to date. In this study, S. cerevisiae was engineered with a push-pull-restrain strategy to efficiently produce tyrosol and salidroside from glucose. The biosynthetic pathways of ethanol, phenylalanine, and tryptophan were restrained by disrupting PDC1, PHA2, and TRP3. Subsequently, tyrosol biosynthesis was enhanced with a metabolic pull strategy of introducing PcAAS and EcTyrAM53I/A354V. Moreover, a metabolic push strategy was implemented with the heterologous expression of phosphoketolase (Xfpk), and then erythrose 4-phosphate was synthesized simultaneously by two pathways, the Xfpk-based pathway and the pentose phosphate pathway, in S. cerevisiae. Furthermore, the heterologous expression of Xfpk alone in S. cerevisiae efficiently improved tyrosol production compared with the coexpression of Xfpk and phosphotransacetylase. Finally, the tyrosol yield increased by approximately 135-folds, compared with that of parent strain. The total amount of tyrosol and salidroside with glucose fed-batch fermentation was over 10 g/L and reached levels suitable for large-scale production. 相似文献
107.
108.
Structure and transcription of genes within the β-hbd-adh1 region of Clostridium acetobutylicum P262
Jonathan S. Youngleson Fu-Pang Lin Sharon J. Reid David R. Woods 《FEMS microbiology letters》1995,125(2-3):185-191
Abstract The 1.2-kb DNA fragment upstream of the linked β- hbd (3-hydroxybutyryl-CoA dehydrogenase) and adh1 (NADPH-dependent alcohol dehydrogenase) genes from Clostridium acetobutylicum P262 was sequenced. The upstream region contained an open reading frame (ORFB) which was found to have 44% amino acid identity to the fixB gene products of yRhizobium and Azorhizobium . The β- hbd and ORFB genes were expressed during the acidogenic and solventogenic phases. The β- hbd gene was transcribed on a single mRNA species of 2.0 kb, whereas the ORFB gene was transcribed on two species of mRNA of 2.0 and 3.5 kb, respectively. The adh1 gene was induced or derepressed at the pH breakpoint before the onset of solventogenesis and was transcribed on a single species of mRNA of 2.4 kb. 相似文献
109.
Nai-Chi Chen Masato Yoshimura Hong-Hsiang Guan Ting-Yu Wang Yuko Misumi Chien-Chih Lin Phimonphan Chuankhayan Atsushi Nakagawa Sunney I. Chan Tomitake Tsukihara Tzong-Yueh Chen Chun-Jung Chen 《PLoS pathogens》2015,11(10)
Betanodaviruses cause massive mortality in marine fish species with viral nervous necrosis. The structure of a T = 3 Grouper nervous necrosis virus-like particle (GNNV-LP) is determined by the ab initio method with non-crystallographic symmetry averaging at 3.6 Å resolution. Each capsid protein (CP) shows three major domains: (i) the N-terminal arm, an inter-subunit extension at the inner surface; (ii) the shell domain (S-domain), a jelly-roll structure; and (iii) the protrusion domain (P-domain) formed by three-fold trimeric protrusions. In addition, we have determined structures of the T = 1 subviral particles (SVPs) of (i) the delta-P-domain mutant (residues 35−217) at 3.1 Å resolution; and (ii) the N-ARM deletion mutant (residues 35−338) at 7 Å resolution; and (iii) the structure of the individual P-domain (residues 214−338) at 1.2 Å resolution. The P-domain reveals a novel DxD motif asymmetrically coordinating two Ca2+ ions, and seems to play a prominent role in the calcium-mediated trimerization of the GNNV CPs during the initial capsid assembly process. The flexible N-ARM (N-terminal arginine-rich motif) appears to serve as a molecular switch for T = 1 or T = 3 assembly. Finally, we find that polyethylene glycol, which is incorporated into the P-domain during the crystallization process, enhances GNNV infection. The present structural studies together with the biological assays enhance our understanding of the role of the P-domain of GNNV in the capsid assembly and viral infection by this betanodavirus. 相似文献
110.
Wen-Ching Lin Chih-Chun Wen Yung-Hsiang Chen Pei-Wen Hsiao Jiunn-Wang Liao Ching-I Peng Ning-Sun Yang 《PloS one》2015,10(6)
For the development of “medical foods” and/or botanical drugs as defined USA FDA, clear and systemic characterizations of the taxonomy, index phytochemical components, and the functional or medicinal bioactivities of the reputed or candidate medicinal plant are needed. In this study, we used an integrative approach, including macroscopic and microscopic examination, marker gene analysis, and chemical fingerprinting, to authenticate and validate various species/varieties of Wedelia, a reputed medicinal plant that grows naturally and commonly used in Asian countries. The anti-inflammatory bioactivities of Wedelia extracts were then evaluated in a DSS-induced murine colitis model. Different species/varieties of Wedelia exhibited distinguishable morphology and histological structures. Analysis of the ribosomal DNA internal transcribed spacer (ITS) region revealed significant differences among these plants. Chemical profiling of test Wedelia species demonstrated candidate index compounds and distinguishable secondary metabolites, such as caffeic acid derivatives, which may serve as phytochemical markers or index for quality control and identification of specific Wedelia species. In assessing their effect on treating DSS induced-murine colitis, we observed that only the phytoextract from W. chinensis species exhibited significant anti-inflammatory bioactivity on DSS-induced murine colitis among the various Wedelia species commonly found in Taiwan. Our results provide a translational research approach that may serve as a useful reference platform for biotechnological applications of traditional phytomedicines. Our findings indicate that specific Wedelia species warrant further investigation for potential treatment of human inflammatory bowel disease. 相似文献