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61.
62.
Fei Mi Ying Zhang Dan Yang Xiaozhao Tang Pengfei Wang Xiaoxia He Yunrun Zhang Jianyong Dong Yang Cao Chunli Liu Ke-Qin Zhang Jianping Xu 《PloS one》2016,11(2)
During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China. 相似文献
63.
RNA‐seq analysis reveals new candidate genes for drip loss in a Pietrain × Duroc × Landrace × Yorkshire population 下载免费PDF全文
Bojiang Li Kaiqing Liu Qiannan Weng Pinghua Li Wei Wei Qifa Li Jie Chen Ruihua Huang Wangjun Wu Honglin Liu 《Animal genetics》2016,47(2):192-199
Drip loss, one of the most important meat quality traits, is characterized by low heritability. To date, the genetic factors affecting the drip loss trait have not been clearly elucidated. The objective of this study was to identify critical candidate genes affecting drip loss. First, we generated a Pietrain × Duroc × Landrace × Yorkshire commercial pig population and obtained phenotypic values for the drip loss trait. Furthermore, we constructed two RNA libraries from pooled samples of longissimus dorsi muscles with the highest (H group) and lowest (L group) drip loss and identified the differentially expressed genes (DEGs) between these extreme phenotypes using RNA‐seq technology. In total, 25 883 genes were detected in the H and L group libraries, and none was specifically expressed in only one library. Comparative analysis of gene expression levels found that 150 genes were differentially expressed, of which 127 were upregulated and 23 were downregulated in the H group relative to the L group. In addition, 68 drip loss quantitative trait loci (QTL) overlapping with 63 DEGs were identified, and these QTL were distributed mainly on chromosomes 1, 2, 5 and 6. Interestingly, the triadin (TRDN) gene, which is involved in muscle contraction and fat deposition, and the myostatin (MSTN) gene, which has a role in muscle growth, were localized to more than two drip loss QTL, suggesting that both are critical candidate genes responsible for drip loss. 相似文献
64.
The molecular mechanism that controls the proliferation and differentiation of prostate epithelial cells is currently unknown. We previously identified a 44-kDa protein (p44/wdr77) as an androgen receptor-interacting protein that regulates a set of androgen receptor target genes in prostate epithelial cells and prostate cancer. In this study, we found that p44 localizes in the cytoplasm of prostate epithelial cells at the early stage of prostate development when cells are proliferating, and its nuclear translocation is associated with cellular and functional differentiation in adult prostate tissue. We further demonstrated that cytoplasmic p44 protein is essential for proliferation of prostate epithelial cells, whereas nuclear p44 is required for cell differentiation and prostate- specific protein secretion. These studies suggest a novel mechanism by which proliferation and differentiation of prostate epithelial cells are controlled by p44’s location in the cell. 相似文献
65.
66.
Splenic gene expression profiling in White Leghorn layer inoculated with the Salmonella enterica serovar Enteritidis 下载免费PDF全文
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
67.
Xiao-Xiao Li Bun Tsoi Yi-Fang Li Hiroshi Kurihara Rong-Rong He 《The journal of histochemistry and cytochemistry》2015,63(5):301-311
Cardiolipin (CL) is a unique dimeric phospholipid that exists almost exclusively in the inner mitochondrial membrane (IMM) in eukaryotic cells. Two chiral carbons and four fatty acyl chains in CL result in a flexible body allowing interactions with respiratory chain complexes and mitochondrial substrate carriers. Due to its high content of unsaturated fatty acids, CL is particularly prone to reactive oxygen species (ROS)-induced oxidative attacks. Under mild mitochondrial damage, CL is redistributed to the outer mitochondrial membrane (OMM) and serves as a recognition signal for dysfunctional mitochondria, which are rapidly sequestered by autophagosomes. However, peroxidation of CL is far greater in response to severe stress than under normal or mild-damage conditions. The accumulation of oxidized CL on the OMM results in recruitment of Bax and formation of the mitochondrial permeability transition pore (MPTP), which releases Cytochrome c (Cyt c) from mitochondria. Over the past decade, the significance of CL in the function of mitochondrial bioenergy has been explored. Moreover, approaches to analyzing CL have become more effective and accurate. In this review, we discuss the unique structural features of CL as well as the current understanding of CL-based molecular mechanisms of mitophagy and apoptosis. 相似文献
68.
Improving farming practices of soil and water conservation has profound effects on the yield of wheat (Triticum aestivum L.) in dryland farming regions of the Loess Plateau in China. Mulching has proven to be an effective practice to increase crop yield, and possibly contribute to replenishing groundwater. This evaluation study collected and analyzed the data of 1849 observations published in 38 papers using meta-analysis to investigate effects of the mulching practices on wheat yield in terms of different rainfall and regions in comparison with conventional tillage. The main results of the study follow. The effects of the mulching practices were ranked in the order of RFM (ridge–furrow mulching) > MTMC (mulching with two materials combined) > MOM (mulching with other materials) > WSM (wheat straw mulching) > FM (flat mulching). The effects of the mulching practices at the different levels of rainfall during the wheat growing season were in the order: (< 150 mm) > (> 250 mm) > (150–250 mm). The effects of the mulching practices in the different regions were in the order of Henan > Shanxi > Shaanxi > Gansu. WSM, MTMC and FM performed better in improving wheat yield for rainfall of < 150, 150–250 and > 250 mm during the growing season, respectively. The wheat yield with FM, MTMC, MOM and MOM was higher than those with the other mulching practices in Shaanxi, Gansu, Henan and Shanxi. The wheat yield with RFM was 27.4% higher than that with FM, indicating that RFM was the most effective practice to improve wheat yield among all the practices. These findings have important implications for choosing appropriate crop field management to improve wheat yield. 相似文献
69.
During the process optimisation of glucoamylase production by Aspergillus awamori, cell morphology was controlled at such a state that spore aggregation was completely prevented. Samples from five fermentations on complex media using either glucose or starch as carbon source were characterised with a Bohlin CS rheometer. The experimental data were conveniently described in terms of the power law model. 相似文献
70.
Suspension culture of Ajuga lobata D. Don cells provides a method of synthesis of the phytoecdysteroid 20-hydroxyecdysone (20E) which can regulate the molting process of larvae. We characterized the culture conditions to optimize 20E production. Growth of A. lobata D. Don cells fits the logistic equation curve with a growth cycle of 19 days. Medium conductivity was negatively correlated with dry cell weight and 20E accumulation, thus could be used to determine the optimal time for cell harvest. Continuous subculture reduced 20E synthesis, but supplementing medium with 20E precursors mevalonic (MVA), α-Pinene, and nitric oxide (NO) can significantly promote cell growth and influence 20E accumulation. Combination of α-Pinene, MVA, and SNP significantly elevated 20E accumulation, thus may synergistically enhance 20E synthesis in A. lobata D. Don. The optimal concentrations of α-Pinene, MVA, and NO donor SNP in suspension culture were 50 μL L?1, 10 mg L?1, and 80 μmol L?1. 相似文献