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41.
It has been recently established that Klotho coreceptors associate with fibroblast growth factor (FGF) receptor tyrosine kinases (FGFRs) to enable signaling by endocrine-acting FGFs. However, the molecular interactions leading to FGF-FGFR-Klotho ternary complex formation remain incompletely understood. Here, we show that in contrast to αKlotho, βKlotho binds its cognate endocrine FGF ligand (FGF19 or FGF21) and FGFR independently through two distinct binding sites. FGF19 and FGF21 use their respective C-terminal tails to bind to a common binding site on βKlotho. Importantly, we also show that Klotho coreceptors engage a conserved hydrophobic groove in the immunoglobulin-like domain III (D3) of the "c" splice isoform of FGFR. Intriguingly, this hydrophobic groove is also used by ligands of the paracrine-acting FGF8 subfamily for receptor binding. Based on this binding site overlap, we conclude that while Klotho coreceptors enhance binding affinity of FGFR for endocrine FGFs, they actively suppress binding of FGF8 subfamily ligands to FGFR.  相似文献   
42.
F Tao  X Wang  C Ma  C Yang  H Tang  Z Gai  P Xu 《Journal of bacteriology》2012,194(17):4755-4756
Xanthomonas campestris JX, a soil bacterium, is an industrially productive strain for xanthan gum. Here we present a 5.0-Mb assembly of its genome sequence. We have annotated 12 coding sequences (CDSs) responsible for xanthan gum biosynthesis, 346 CDSs encoding carbohydrate metabolism, and 69 CDSs related to virulence, defense, and plant disease.  相似文献   
43.
In response to pathogen recognition by Toll-like receptors (TLRs) on their cell surface, macrophages release lipid mediators and cytokines that are widely distributed throughout the body and play essential roles in host responses. Granulocyte macrophage colony-stimulating factor (GM-CSF) is important for the immune response during infections to improve the clearance of microorganisms. In this study, we examined the release of mediators in response to TLR2 ligands by bone marrow-derived macrophages (BMDMs) primed with GM-CSF. We demonstrated that when stimulated with TLR2 ligands, non-primed BMDMs preferentially produced PGE(2) in greater amounts than LTB(4). However, GM-CSF priming shifted the release of lipid mediators by BMDMs, resulting in a significant decrease of PGE(2) production in response to the same stimuli. The decrease of PGE(2) production from primed BMDMs was accompanied by a decrease in PGE-synthase mRNA expression and an increase in TNF-α and nitric oxide (NO) production. Moreover, some GM-CSF effects were potentiated by the addition of IFN-γ. Using a variety of TLR2 ligands, we established that PGE(2) release by GM-CSF-primed BMDMs was dependent on TLR2 co-receptors (TLR1, TLR6), CD14, MyD88 and the nuclear translocation of NFκB but was not dependent on peroxisome proliferator-activated receptor-γ (PPAR-γ) activation. Indeed, GM-CSF priming enhanced TLR2, TLR4 and MyD88 mRNA expression and phospho-IκBα formation. These findings demonstrate that GM-CSF drives BMDMs to present a profile relevant to the host during infections.  相似文献   
44.
Adherence to TB treatment is the most important requirement for efficient TB control. Migrant TB patients’ “migratory” nature affects the adherence negatively, which presents an important barrier for National TB Control Program in China. Therefore, TB control among migrants is of high importance.The aim of this study is to describe adherence to TB treatment among migrant TB patients and to identify factors associated with adherence. A total of 12 counties/districts of Shandong Province, China were selected as study sites. 314 confirmed smear positive TB patients were enrolled between August 2nd 2008 and October 17th 2008, 16% of whom were non-adherent to TB therapy. Risk factors for non-adherence were: the divorced or bereft of spouse, patients not receiving TB-related health education before chemotherapy, weak incentives for treatment adherence, and self supervision on treatment. Based on the risk factors identified, measures are recommended such as implementing health education for all migrant patients before chemotherapy and encouraging primary care workers to supervise patients.  相似文献   
45.
Effect of salinity (15, 25, 35, 45, and 55‰) on growth, biochemical composition, and lipid productivity of Nannochloropsis oculata CS 179 was investigated under controlled cultivation in a 19‐day study. The results demonstrate that the dry biomass of N. oculata was the highest at a salinity of 25‰ among the treatments in the first 10‐day cultivation (P<0.05). During days 14–19 (stage III), the dry biomass productivity was the highest at a salinity of 35‰ (P<0.05). The algae had the highest chlorophyll a content (26.47 mg g?1) at 25‰ in stage I, and it decreased continuously at stage III. Protein content (as% of dry biomass) of algae reached the highest value of 42.25 ± 2.10% at 15‰, and the lipid content was the highest of 32.11 ± 1.30% of dry biomass at 25‰. However, the lipid productivity of these algae was the highest at 35‰ (64.71 mg L?1 d?1; P<0.001). C16 series content was the highest among the total fatty acid methyl esters (FAME), and eicosapentaenoic acid C20:5n‐3 (EPA) content was high at the low salinity. Fatty acid profiles of N. oculata varied significantly under different salinities.  相似文献   
46.
山东省忍冬科植物资源及其园林应用   总被引:4,自引:0,他引:4  
忍冬科植物是优秀的园林观赏植物,其形态优美,不但可以观花赏果,还具芳香,为园林植物造景提供了广泛的资源。山东省忍冬科植物共有24种、4变种及2变型,但目前在园林应用中,尚未引起人们足够的重视和研究。文章简要介绍了山东省忍冬科植物的分布情况;通过分析忍冬科植物的观赏特性,探讨了它们的园林用途;最后对其开发利用和保护提出了建议。  相似文献   
47.
In plants, the endoplasmic reticulum (ER)-associated oleate desaturase (FAD2) is the key enzyme responsible for the production of linoleic acid in non-photosynthetic tissues. In this study, we report the characterization of a seed-specific isoform of microsomal omega-6 fatty acid desaturase gene (FAD2-1B) sharing high sequence similarity with FAD2-1 from soybean. Several potential promoter elements including seed-specific motifs are found in the 5'-flanking region of FAD2-1B gene. The ORF of FAD2-1B is 1161 bp long and encodes a protein of 387 amino acids. This deduced protein holds three histidine boxes and four putative membrane-spanning helices, and possesses a signal for endoplasmic reticulum retention at C-terminal. Yeast cells transformed with the plasmid construct containing soybean FAD2-1B accumulate an appreciable amount of linoleic acid (18:2), normally not present in wild-type yeast cells, indicating that the cloned gene encodes a functional FAD2 enzyme. Both semi-quantitative RT-PCR and in silico analysis show that FAD2-1B gene is specifically expressed in developing seeds of soybean.  相似文献   
48.
The terminal step of soybean cysteine synthesis is catalyzed by O-acetylserine(thiol)lyase (OAS-TL, EC 2.5.1.47). In this study, we isolated and characterized an OAS-TL gene from a wild soybean material (designated as GsOAS-TL1). GsOAS-TL1 cDNA sequence showed strict conservation at both nucleotide and amino acid levels compared with that from cultivated soybean. Genomic structure analysis of GsOAS-TL1 indicated that it contained 10 exons and 9 introns in the coding region with conserved exon sizes and intron locations compared with Arabidopsis thaliana OAS-TL-like genes. Among the complete GsOAS-TL1 cDNA and three part-deletion fragments, only expression of the full-length cDNA could rescue the NK3 cys Escherichia coli auxotroph, which was coherent with the assayed enzyme activity of purified fusion proteins. For RT-PCR analysis in different wild soybean tissues, GsOAS-TL1 showed lower expression in roots and developing seeds, whereas total OAS-TL activity of corresponding tissues showed significantly higher level in seeds than other tissues. To our knowledge, this is the first report on cloning and characterization of an OAS-TL gene from wild soybean. Our results are informative to further elucidate the function and evolution of OAS-TL in soybean.  相似文献   
49.
Apolipoprotein E (APOE) plays a significant role in lipid metabolism and has been implicated in the growth and repair of injured neurons. Two small studies have suggested an association between APOE genotype and cerebral palsy. We investigated if APOE genotype is associated with an increased risk for cerebral palsy, influences the type of cerebral palsy or interacts with prenatal viral infection to influence risk of cerebral palsy. The population-based case-control study comprised newborn screening cards of 443 Caucasian patients with cerebral palsy and 883 Caucasian matched controls. APOE genotyping was performed on DNA extracted from dried blood spots. Allelic and genotypic frequencies did not differ between cases and controls and combined frequencies were 0.10 (ε2), 0.76 (ε3), 0.14 (ε4), 0.03 (ε2/ε2), 0.10 (ε2/ε3), 0.03 (ε2/ε4), 0.02 (ε4/ε4), 0.21 (ε3/ε4), 0.61 (ε3/ε3). APOE genotype was correlated with cerebral palsy, type of cerebral palsy, gestation at birth and the presence of viral nucleic acids detected in previous work. Analysis by gestational age (all gestational ages, ≥37, 32–36 and <32 weeks) and type of cerebral palsy (all types, diplegia, hemiplegia and quadriplegia) showed no association between APOE genotype and cerebral palsy in this Caucasian population. An association between prenatal viral infection, APOE genotype and cerebral palsy was not demonstrated. These results did not confirm an association between APOE genotype, cerebral palsy, type of cerebral palsy and prenatal infection in a Caucasian population. Given the low frequency of APOE ε2 and some of the heterozygote and homozygote combinations in this study, a larger study is assessing this further.  相似文献   
50.
将伪狂犬病病毒TK^-/gG^-/LacZ^ 突变株的基因组DNA与含有缺失的gG基因的转移质粒pUSKBB共转染猪肾传代细胞PK-15,待完全病变后收获病毒进行空斑试验,用PCR筛选gG缺失的重组病毒。空斑纯化3次后,随机挑取空斑进行PCR扩增,证实所获得的病毒为均一的TK^-/gG^-缺失株。遗传稳定性试验表明该重组病毒能在PK-15细胞上稳定遗传,动物试验表明该缺失株对Balb/c小鼠极为安全且能保护Balb/c小鼠抵抗致死量PRV强毒的攻击。该突变株的获得为我国伪狂犬病的控制和根除奠定了基础。  相似文献   
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