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It is a long-standing question as to which genes define the characteristic facial features among different ethnic groups. In this study, we use Uyghurs, an ancient admixed population to query the genetic bases why Europeans and Han Chinese look different. Facial traits were analyzed based on high-dense 3D facial images; numerous biometric spaces were examined for divergent facial features between European and Han Chinese, ranging from inter-landmark distances to dense shape geometrics. Genome-wide association studies(GWAS) were conducted on a discovery panel of Uyghurs. Six significant loci were identified, four of which, rs1868752, rs118078182, rs60159418 at or near UBASH3B, COL23A1, PCDH7 and rs17868256 were replicated in independent cohorts of Uyghurs or Southern Han Chinese. A prospective model was also developed to predict 3D faces based on top GWAS signals and tested in hypothetic forensic scenarios.  相似文献   
3.
α1‐adrenoceptors (α1‐ARs) stimulation has been found to enhance excitatory processes in many brain regions. A recent study in our laboratory showed that α1‐ARs stimulation enhances glutamatergic transmission via both pre‐ and post‐synaptic mechanisms in layer V/VI pyramidal cells of the rat medial prefrontal cortex (mPFC). However, a number of pre‐synaptic mechanisms may contribute to α1‐ARs‐induced enhancement of glutamate release. In this study, we blocked the possible post‐synaptic action mediated by α1‐ARs to investigate how α1‐ARs activation regulates pre‐synaptic glutamate release in layer V/VI pyramidal neurons of mPFC. We found that the α1‐ARs agonist phenylephrine (Phe) induced a significant enhancement of glutamatergic transmission. The Phe‐induced potentiation was mediated by enhancing pre‐synaptic glutamate release probability and increasing the number of release vesicles via a protein kinase C‐dependent pathway. The mechanisms of Phe‐induced potentiation included interaction with both glutamate release machinery and N‐type Ca2+ channels, probably via a pre‐synaptic Gq/phospholipase C/protein kinase C pathway. Our results may provide a cellular and molecular mechanism that helps explain α1‐ARs‐mediated influence on PFC cognitive functions.

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4.
A novel bacterial strain, designated SGD-1123T was isolated from Chorao Island, in Goa Province, India. The strain was found to be able to grow at 15–42 °C, pH 5–12 and 0–12 % (w/v) NaCl. The whole cell hydrolysates were found to contain meso-diaminopimelic acid, galactose and arabinose. The major fatty acids were identified as iso-C15:0 and anteiso-C15:0, MK-7 was identified as the predominant menaquinone and the predominant polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified aminolipid. The genomic DNA G+C content was determined to be 44.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences placed the isolate within the genus Bacillus and further revealed that strain SGD-1123T had highest sequence similarity with Bacillus aquimaris, and forms a separate clade with its closest relatives i.e. B. aquimaris, Bacillus vietnamensis and Bacillus marisflavi, with which it shares 94.5, 94.1 and 94.1 % similarity respectively. The phylogenetic, chemotaxonomic and phenotypic analyses indicated that strain SGD-1123T represents a novel species within the genus Bacillus, for which the name Bacillus enclensis is proposed. The type strain is SGD-1123T (NCIM 5450T=CCTCC AB 2011125T).  相似文献   
5.
A Bacillus-like isolate, strain FJAT-13831T, isolated from the No. 1 pit soil of Emperor Qin’s Terra-cotta Warriors in Xi’an City, China, was studied to determine its taxonomic status. Dominant fatty acids of this organism included iso-C15:0, iso-C17:0, C16:0, iso-C13:0, anteiso-C15:0, and iso-C17:1ω5c. Comparative 16S rRNA gene sequence analysis confirmed the affiliation of this isolate to the genus Bacillus and indicated that it was closely related to Bacillus pseudomycoides DSM 12442T (99.72 % similarity). A phylogenetic analysis of the gyrB gene sequence similarities exhibited independent clustering of the isolate FJAT-13831T and showed 93.8 % (<95 %) sequence similarity with its closest phylogenetic neighbour B. pseudomycoides DSM 12442T. Separate standing of the strain FJAT-13831T was supported by a whole genome-based phylogenetic analysis with an average nucleotide identity value of 91.47 (<95 %) between isolate FJAT-13831T and B. pseudomycoides DSM 12442T and was consistent with the results of DNA–DNA hybridization (69.1 % relatedness). These findings support the conclusion that the isolate FJAT-13831T represents a novel species, for which the name Bacillus bingmayongensis sp. nov. is proposed. The type strain is FJAT-13831T (= CGMCC 1.12043T = DSM 25427T).  相似文献   
6.
Triacylglycerols (TAGs), synthesized in the microsomal membranes of eukaryotes, serve as a primary storage form of carbon and energy in microorganisms. For this reason, TAGs produced by organisms have great potential to become biofuels and facilitate researchers to look for alternative renewable sources of energy. The present study describes the identification and functional characterization of a type-2 diacylglycerol acyltransferase from Rhodosporidium diobovatum, designated as RdDGAT, which catalyzed the final step of TAG synthesis. A full-length cDNA clone for RdDGAT was obtained, and its biological activity was proven by being expressed in a Saccharomyces cerevisiae quadruple mutant that was defective in TAG synthesis. Enzymatic assays were performed and finally the existence of TAGs in the transformed Saccharomyces cerevisiae quadruple mutant was determined using the method of thin-layer chromatography. Substrate preference experiments revealed that RdDGAT preferred unsaturated fatty acids over saturated ones. Through further analysis, we assume that the evolution and expression characteristics of the RdDGAT gene perhaps is the result of adaption to its oligotrophic and cold living environment.  相似文献   
7.
凉山州新银合欢根瘤菌的共生有效性及遗传多样性   总被引:1,自引:0,他引:1  
【目的】研究分离自四川凉山州新银合欢根瘤菌的遗传多样性和共生有效性。【方法】采用16S rRNA RFLP、BOX-PCR、AFLP、多位点持家基因序列的联合分析及无氮水培法对33株供试新银合欢根瘤菌的遗传多样性和共生有效性进行研究。【结果】分析表明,3种方法在属水平的分群结果具有较好的一致性,有1个Mesorhizobium属的菌株、3个Bradyrhizobium属的菌株、3个Rhizobium属的菌株,26个相似度较高的菌株属Sinorhizobium。16S rRNA-recA-atpD-glnII序列联合构建的新银合欢根瘤菌系统发育树表明,SCAU203、SCAU211可能分别是Rhizobium和Bradyrhizobium的新类群,另外3个代表菌株分别位于Sinorhizobium、Mesorhizobium、Bradyrhizobium分支,分别与S.americanum、M.Plurifarium、R.huautlense亲缘关系最近。无氮水培接种试验筛选出2个共生固氮效果好、与不接种对照处理差异达显著水平的菌株SCAU229和SCAU307,有3个菌株不仅不具共生有效性,甚至不利于宿主的生长,其余84%的供试菌为低效或无效菌株。【结论】凉山州新银合欢根瘤菌具有丰富的遗传多样性,分布于4个属:Rhizobium、Bradyrhizobium、Mesorhizobium、Bradyrhizobium,79%为Sinorhizobium属的菌株,优势菌群为Sinorhizobium。该区的新银合欢根瘤菌大多数的共生有效性差。  相似文献   
8.
【目的】探讨反义RNA技术介导的大肠杆菌非必需基因rpsF基因沉默导致菌体生长受抑制的原因。【方法】将rpsF基因5'端41-230 bp的片段反向插入带有末端配对结构的反义表达载体pHN678,获得重组质粒,导入大肠杆菌宿主获得反义RNA菌株Escherichia.coli/pHNF,并用诱导剂IPTG诱导反义RNA表达,通过与对照菌E.coli/pHN678的液体生长状态差异判断菌体生长表型;采用Real time RT-PCR方法跟踪分析转录水平。【结果】构建了针对rpsF的反义RNA菌株,且其生长受抑制程度与IPTG浓度呈正相关。IPTG浓度为100μmol/L时,菌体生长未受抑制,但靶基因rpsF的mRNA量降低了36%,而rpsR是位于同一操纵子下游的必需基因,其转录水平却未受影响;IPTG浓度为200μmol/L时,菌体生长明显受抑制,经分析发现rpsR转录水平降低了12%。【结论】反义RNA菌株E.coli/pHNF生长受抑制的原因是由于此反义RNA引起了同一操纵子下另一必需基因rpsR的转录水平降低。  相似文献   
9.
The drug–serum albumin interaction plays a dominant role in drug efficacy and disposition. The glycation of serum albumin that occurs during diabetes may affect its drug‐binding properties in vivo. In order to evaluate the interactivity characteristics of cyanidin‐3‐O‐glucoside (C3G) with human serum albumin (HSA) and glycated human serum albumin (gHSA), this study was undertaken using multiple spectroscopic techniques and molecular modeling analysis. Time‐resolved fluorescence and the thermodynamic parameters indicated that the quenching mechanism was static quenching, and hydrogen bonding and Van der Waals force were the main forces. The protein fluorescence could be quenched by C3G, whereas the polarity of the fluorophore was not obviously changed. C3G significantly altered the secondary structure of the proteins. Furthermore, the interaction force that existed in the HSA–C3G system was greater than that in the gHSA–C3G system. Fluorescence excitation emission matrix spectra, red edge excitation shift, Fourier transform infrared spectroscopy and circular dichroism spectra provided further evidence that glycation could inhibit the binding between C3G and proteins. In addition, molecular modeling analysis supported the experimental results. The results provided more details for the application of C3G in the treatment of diabetes.  相似文献   
10.
Differing from the weakly antiaromatic B80 buckyball, the medium-sized C 1–B28 and D 2h –B38, as well as their mono- to tetra-anions, are highly aromatic, as indicated by the negative nucleus-independent chemical shifts (NICSs) at their cage centers. The interior cavities and high aromaticity of the B28 and B38 cages render them very promising hosts to accommodate diverse metal atoms. Accordingly, we carried out systematic density functional theory (DFT) computations on the structures, stabilities and electronic properties of metalloborofullerenes MB n (M?=?Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La and Ti; n?=?28 and 38). Among them, besides the recently reported M@B38(M?=?Sc, Y and Ti) [Lu et al. (2015) Phys Chem Chem Phys 17:20897–20902], Ti@B28 and M@B38 (M?=?Ca and La) also favor endohedral structures with large binding energies, and are suggested promising targets for experimental applications. Note that Ti@B28 is the first endohedral derivative based on the new B28 fullerene, and La@B38 features the largest metal size inside a B38 cage thus far. These endohedral derivatives, as exemplified by Ca@B38, may exhibit σ and π double aromaticity over the whole cage surface, indicating their considerable stability. In contrast, the other metals prefer to reside at the exterior cage surface, due mainly to the mismatch of their sizes with the boron cages, though the size match is not the only factor to determine their doping form. Furthermore, the infrared absorption spectra and 11B nuclear magnetic resonance spectra of the three new M@B n complexes were computed to assist future experimental characterization.
Graphical Abstract Putting more metals into medium-sized boron cages!
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