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1.
Salmonella enterica serovar Enteritidis (SE) is a foodborne pathogen that can threaten human health through contaminated poultry products. Live poultry, chicken eggs and meat are primary sources of human salmonellosis. To understand the genetic resistance of egg‐type chickens in response to SE inoculation, global gene expression in the spleen of 20‐week‐old White Leghorn was measured using the Agilent 4 × 44 K chicken microarray at 7 and 14 days following SE inoculation (dpi). Results showed that there were 1363 genes significantly differentially expressed between inoculated and non‐inoculated groups at 7 dpi (I7/N7), of which 682 were up‐regulated and 681 were down‐regulated genes. By contrast, 688 differentially expressed genes were observed at 14 dpi (I14/N14), of which 371 were up‐regulated genes and 317 were down‐regulated genes. There were 33 and 28 immune‐related genes significantly differentially expressed in the comparisons of I7/N7 and I14/N14 respectively. Functional annotation revealed that several Gene Ontology (GO) terms related to immunity were significantly enriched between the inoculated and non‐inoculated groups at 14 dpi but not at 7 dpi, despite a similar number of immune‐related genes identified between I7/N7 and I14/N14. The immune response to SE inoculation changes with different time points following SE inoculation. The complicated interaction between the immune system and metabolism contributes to the immune responses to SE inoculation of egg‐type chickens at 14 dpi at the onset of lay. GC, TNFSF8, CD86, CD274, BLB1 and BLB2 play important roles in response to SE inoculation. The results from this study will deepen the current understanding of the genetic response of the egg‐type chicken to SE inoculation at the onset of egg laying.  相似文献   
2.
马铃薯是淀粉生产中重要的农作物之一,而可溶性淀粉合成酶SSⅢ是可溶性淀粉合成酶的主要活性成分,通过基因工程的手段来研究SSⅢ基因在淀粉合成中的功能可以用于改良马铃薯淀粉的品质.本研究采用根癌农杆菌介导法将强组成型表达启动子CaMV 35S驱动的可溶性淀粉合成酶SSⅢ基因的RNA干扰表达载体导入马铃薯栽培品种克新1号和克新4号中,获得了65株卡那霉素抗性植株.对抗性植株PCR检测结果表明,SSⅢ基因的干扰片段已整合到马铃薯基因组中,RT-PCR检测表明SSⅢ基因在转录水平上受到了明显抑制.该研究为马铃薯淀粉品质的改良奠定了基础.  相似文献   
3.
Cordyceps militaris, the type species of genus Cordyceps, is one of the most popular mushrooms and a nutraceutical in eastern Asia. It is considered a model organism for the study of Cordyceps species because it can complete its life cycle when cultured in vitro. In the present study, the occurrence and sequence variation of SSU rDNA group I introns, Cmi.S943 and Cmi.S1199, among different isolates of C. militaris were analyzed. Based on the secondary structure predictions, the Cmi.S943 intron has been placed in subgroup IC1, and the Cmi.S1199 intron has been placed in subgroup IE. No significant similarity between Cmi.S943 and Cmi.S1199 suggested different origins. Three genotypes, based on the frequency and distribution of introns, were described to discriminate the 57 surveyed C. militaris strains. It was found that the genotype was related to the stroma characteristics. The stromata of all of the genotype II strains, which possessed only Cmi.S943, could produce perithecium. In contrast, the stromata of all genotype III strains, which had both Cmi.S943 and Cmi.S1199, could not produce perithecium. Cmi.S1199 showed the lowest level of intra-specific variation among the tested strains. Group I introns can be lost during strain cross-mating. Therefore, we presumed that during cross-mating and recombination, intron loss could be driven by positive Darwinian selection due to the energetic cost of transcribing long introns.  相似文献   
4.
栖息地破碎化、人为干扰等因素影响着中华鬣羚(Capricornis sumatraensis)的生存。目前, 中华鬣羚的行为研究还比较匮乏, 因此有必要构建中华鬣羚的行为谱及PAE (posture-act-environment)编码系统, 以期促进其基础行为资料的完善, 为深入开展科学研究和保护工作奠定基础。本文旨在: (1)参照国内常用的动物行为编码方法, 以“姿势-动作-环境”为轴心, 建立中华鬣羚的行为谱及PAE编码系统, 并随机抽取20%的中华鬣羚视频作为检测样本, 对行为谱的实际使用效果进行测试。(2)对中华鬣羚的行为数据进行统计并通过计算行为多样性指数, 分析各特定年龄组间的行为多样性差异, 检验特定年龄组与行为多样性指数间的相关性。结果显示: (1)通过区别和归类中华鬣羚的10种姿势、80种动作、9种环境、78种行为, 首次建立了中华鬣羚的行为谱及PAE编码系统。经测试, 该行为谱能够客观地对中华鬣羚行为进行识别和归类。(2)与亚成体和幼体相比, 中华鬣羚成体特定行为类型的行为多样性指数(Avariable)、绝对行为多样性指数(A)、相对行为多样性指数(r)和校正行为多样性指数(r-variable)均为最高; 中华鬣羚亚成体特定行为类型的行为多样性指数(Avariable)、绝对行为多样性指数(A)、相对行为多样性指数(r)介于成体和幼体之间; 中华鬣羚幼体的特定行为类型的行为多样性指数(Avariable)、绝对行为多样性指数(A)和相对行为多样性指数(r)最低, 校正行为多样性指数(r-variable)高于亚成体。(3)中华鬣羚行为谱可用于其行为学研究, 今后应获取繁殖行为的图像数据, 更新行为谱及PAE编码系统。(4) 3个特定年龄组中华鬣羚的各行为多样性指数之间差异不显著(F = 0.013, P = 0.987), 从幼体到成体, 中华鬣羚的特定行为类型的行为多样性指数(Avariable)、绝对行为多样性指数(A)和相对行为多样性指数(r)随年龄的增大呈递增趋势。综上所述, 我们应深入研究中华鬣羚行为学, 为其保护工作提供科学支撑。  相似文献   
5.
The Functional Annotation of Animal Genomes (FAANG) Consortium recently held a Gathering On FAANG (GO‐FAANG) Workshop in Washington, DC on October 7–8, 2015. This consortium is a grass‐roots organization formed to advance the annotation of newly assembled genomes of domesticated and non‐model organisms ( www.faang.org ). The workshop gathered together from around the world a group of 100+ genome scientists, administrators, representatives of funding agencies and commodity groups to discuss the latest advancements of the consortium, new perspectives, next steps and implementation plans. The workshop was streamed live and recorded, and all talks, along with speaker slide presentations, are available at www.faang.org . In this report, we describe the major activities and outcomes of this meeting. We also provide updates on ongoing efforts to implement discussions and decisions taken at GO‐FAANG to guide future FAANG activities. In summary, reference datasets are being established under pilot projects; plans for tissue sets, morphological classification and methods of sample collection for different tissues were organized; and core assays and data and meta‐data analysis standards were established.  相似文献   
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7.
The NF-kB pathway plays an important role in regulating the immunity response in animals. In this study, small interfering RNAs (siRNA) were used to specifically inhibit NF-kB 1 expression and to elucidate the role of NF-kB in the signal transduction pathway of the Salmonella challenge in the chicken HD11 cell line. The cells were transfected with either NF-kB 1 siRNA, glyceraldehyde 3-phosphate dehydrogenase siRNA (positive control) or the negative control siRNA for 24 h, followed by Salmonella enteritidis (SE) challenge or non-challenge for 1 h and 4 h. Eight candidate genes related to the signal pathway of SE challenge were selected to examine the effect of NF-kB 1 inhibition on their expressions by mRNA quantification. The results showed that, with a 36% inhibition of NF-kB 1 expression, gene expression of both Toll-like receptor (TLR) 4 and interleukin (IL)-6 was consistently and significantly increased at both 1 h and 4 h following SE challenge, whereas the gene expression of MyD88 and IL-1β was increased at 1 h and 4 h, respectively. These findings suggest a likely inhibitory regulation by NF-kB 1, and could lay the foundation for studying the gene network of the innate immune response of SE infection in chickens.  相似文献   
8.
9.
Many wild and cultivated cool-season grass species are naturally infected with fungal endophytes of the genera Neotyphodium and Epichlo?. These associations generally are considered mutualistic with the plants benefiting from reduced herbivory and the fungi benefiting from nutrients supplied by the plants. The fungi secrete proteins that might have a role in the interspecies symbiosis. In the interaction between Poa ampla Merr. and the endophyte Neotyphodium sp., a fungal chitinase was detected in the apoplastic protein fraction. The chitinase was also the major protein secreted in culture. Sequence analysis of the chitinase revealed it has a low level of amino acid sequence identity to other fungal chitinases and one of the conserved active site residues is altered. DNA gel-blot analysis indicated the chitinase was encoded by a single gene. Expression of similar chitinases also was detected in endophyte-infected tall fescue (Festuca arundinacea Schreb.), perennial ryegrass (Lolium perenne L.) and Chewings fescue (Festuca rubra L. subsp. fallax [Thuill] Nyman). This is the first report of an endophyte chitinase expressed in the infected host grass. As a secreted hydrolytic enzyme, the chitinase might have roles in the nutrition, growth or defense of the endophyte.  相似文献   
10.
Lineage-specific gene loss is considered one of the processes contributing to speciation and genome diversity. Such gene loss has been inferred from interspecies comparisons of orthologous DNA segments. Examples of intraspecific gene loss are rare. Here we report identification of a gene, designated Crs-1 (creeping specific-1), that appears to be in the process of being lost from heterozygous populations of the species creeping bentgrass (Agrostis stolonifera). The Crs-1 gene encodes a protein with an N-terminal dirigent protein domain and a C-terminal lectin domain and is similar to the maize (Zea mays) beta-glucosidase aggregating factor. Most individual creeping bentgrass plants examined are lacking Crs-1. Some individuals are hemizygous for the Crs-1 locus, indicating major haplotype noncolinearity at that locus. Crs-1 was not detected in several other Agrostis species, indicating it is being lost from the genus. The Crs-1 locus in creeping bentgrass provides a rare example of the evolutionary process of gene loss occurring within a plant species.  相似文献   
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