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961.
962.
Yi Liu Aixue Li Xin Wang Lihua Sui Min Li Yanbin Zhao Bing Liu Lin Zeng Zhaozeng Sun 《Immunogenetics》2013,65(4):273-280
Since rhesus monkeys of Chinese origin have gained greater utilization in recent years, it is urgent to investigate the major histocompatibility complex (MHC) immunogenetics of Chinese rhesus macaques. In this study, we identified 81 Mamu-B sequences using complementary DNA cloning and sequencing on a cohort of 58 rhesus monkeys derived from three local populations of China. Twenty of these Mamu-B alleles are novel and four of them represent new lineages. Although more alleles are shared among different populations than Mamu-A locus, the Mamu-B allelic repertoires found in these three populations of Chinese macaques are largely independent, which underscores the MHC polymorphism among different populations of Chinese rhesus macaques. Our results are an important addition to the limited MHC immunogenetic information available for rhesus macaques of Chinese origin. 相似文献
963.
Yan-Kai Zhang Kai-Jun Zhang Jing-Tao Sun Xian-Ming Yang Cheng Ge Xiao-Yue Hong 《Microbial ecology》2013,65(3):731-739
Wolbachia are endosymbiotic bacteria that commonly infect arthropods and cause reproductive disorders in host. Within several Tetranychus species, Wolbachia have been detected and shown to affect their reproduction. However, little is known about their transmission and distribution patterns in natural populations of Tetranychus species. Here, we used multilocus sequence typing to confirm Wolbachia infection status and examined the relationship between Wolbachia infection status and host phylogeny, mitochondrial diversity, and geographical range in five Tetranychus species (Tetranychus truncatus, Tetranychus urticae, Tetranychus pueraricola, Tetranychus phaselus, and Tetranychus kanzawai) from 21 populations in China. The prevalence of Wolbachia within the five Tetranychus species ranged from 31.4 to 100 %, and the strains were remarkably diverse. Together, these observations indicate that Wolbachia was introduced to these populations on multiple separate occasions. As in other arthropods, the same Tetranychus species can accommodate very different strains, and identical Wolbachia occasionally infect different species. These observations suggest that Wolbachia are transmitted both vertically and horizontally. Horizontally, transmission is probably mediated by the host plants. The distribution patterns of Wolbachia were quite different among populations of the same species, suggesting that the dynamics of Wolbachia in nature may be affected by ecological and other factors. 相似文献
964.
Bin Yu Xiao-Nan Sun Xiao-Jing Shi Ping-Ping Qi Yuan Fang En Zhang De-Quan Yu Hong-Min Liu 《Steroids》2013,78(11):1134-1140
The stereoselective and metal-free protocol involving a cascade aldol/cyclization process for the synthesis of steroidal (E, E) dienamides from steroidal α, α-dicyanoalkene was reported. This protocol efficiently achieved the construction of CC bond and selective conversion of cyano group into carboxamide in one-pot procedure under mild condition. Further biological evaluation showed that some of these compounds had moderate to excellent cytotoxic activities against all the tested cancer cell lines and were more potent than well-known drug 5-fluorouracil. Particularly, compound 3c represented excellent inhibitory effect against MCF-7 (IC50 = 0.76 μM), which was about 10-fold more potent than 5-fluorouracil. 相似文献
965.
E.-N. Yang G. M. Rosewarne S. A. Herrera-Foessel J. Huerta-Espino Z.-X. Tang C.-F. Sun Z.-L. Ren R. P. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(7):1721-1732
Chapio is a spring wheat developed by CIMMYT in Mexico by a breeding program that focused on multigenic resistances to leaf rust and stripe rust. A population consisting of 277 recombinant inbred lines (RILs) was developed by crossing Chapio with Avocet. The RILs were genotyped with DArT markers (137 randomly selected RILs) and bulked segregant analysis conducted to supplement the map with informative SSR markers. The final map consisted of 264 markers. Phenotyping against stripe rust was conducted for three seasons in Toluca, Mexico and at three sites over two seasons (total of four environments) in Sichuan Province, China. Significant loci across the two inter-continental regions included Lr34/Yr18 on 7DS, Sr2/Yr30 on 3BS, and a QTL on 3D. There were significant genotype × environment interactions with resistance gene Yr31 on 2BS being effective in most of the Toluca environments; however, a late incursion of a virulent pathotype in 2009 rendered this gene ineffective. This locus also had no effect in China. Conversely, a 5BL locus was only effective in the Chinese environments. There were also complex additive interactions. In the Mexican environments, Yr31 suppressed the additive effect of Yr30 and the 3D locus, but not of Lr34/Yr18, while in China, the 3D and 5BL loci were generally not additive with each other, but were additive when combined with other loci. These results indicate the importance of maintaining diverse, multi-genic resistances as Chapio had stable inter-continental resistance despite the fact that there were QTLs that were not effective in either one or the other region. 相似文献
966.
Suli Sun Moon Young Kim Kyujung Van Yin-Won Lee Baodu Li Suk-Ha Lee 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(8):2029-2038
Phomopsis seed decay (PSD), primarily caused by Phomopsis longicolla, is a major contributor to poor soybean seed quality and significant yield loss, particularly in early maturing soybean genotypes. However, it is not yet known whether PSD resistance is associated with early maturity. This study was conducted to identify quantitative trait loci (QTLs) for resistance to PSD and days to maturity using a recombinant inbred line (RIL) population derived from a cross between the PSD-resistant Taekwangkong and the PSD-susceptible SS2-2. Based on a genetic linkage map incorporating 117 simple sequence repeat markers, QTL analysis revealed two and three QTLs conferring PSD resistance and days to maturity, respectively, in the RIL population. Two QTLs (PSD-6-1 and PSD-10-2) for PSD resistance were identified in the intervals of Satt100–Satt460 and Sat_038–Satt243 on chromosomes 6 and 10, respectively. Two QTLs explained phenotypic variances in PSD resistance of 46.3 and 14.1 %, respectively. At the PSD-6-1 QTL, the PSD-resistant cultivar Taekwangkong contributed the allele with negative effect decreasing the infection rate of PSD and this QTL does not overlap with any previously reported loci for PSD resistance in other soybean genotypes. Among the three QTLs for days to maturity, two (Mat-6-2 and Mat-10-3) were located at positions similar to the PSD-resistance QTLs. The identification of the QTLs linked to both PSD resistance and days to maturity indicates a biological correlation between these two traits. The newly identified QTL for resistance to PSD associated with days to maturity in Taekwangkong will help improve soybean resistance to P. longicolla. 相似文献
967.
Wei Wang Xiaofeng Ji Cui Yuan Fangqun Dai Jiancheng Zhu Mi Sun 《Indian journal of microbiology》2013,53(4):477-481
Catalase plays an important role in the metabolism of marine bacteria and has potential impact on the marine environment. Four PCR primers were designed to amplify the catalase gene fragments in marine bacteria by applying metagenomic DNA from Yellow Sea surface water as the template. Of the four reproducible target PCR products, the longest one with 900 bp were chosen for catalase gene library construction by the T-vector and the white Escherichia coli colonies in the library was screened through restriction-digesting the reamplified insert fragments by the selected restriction endonuclease MboI, and then the bands of the resulting products were displayed in the agarose gel by electrophoresis. The unique restriction fragment length polymorphism (RFLP) pattern was selected and the corresponding catalase gene fragments were sequenced, which verified that every unique RFLP pattern represented one type of catalase. This PCR–RFLP method above was established to investigate the bacterial catalase diversity in seawater. 相似文献
968.
Yunfeng Zha Jiexiong Xie Ye Chen Chunya Wei Wanjun Zhu Jidang Chen Haitao Qi Liangquan Zhang Long Sun Xiaozhan Zhang Pei Zhou Zhenpeng Cao Wenbao Qi Minze Zhang Zhen Huang Guihong Zhang 《Indian journal of microbiology》2013,53(4):496-498
The primary objective of this 3 years study was to determine the prevalence of porcine pathogens of the lungs of swine in swine farms in southern China. A total of 5,420 samples were collected from 200 swine farms. The bacterium that was most commonly isolated was Streptococcus suis, with 10.24 % of the samples being positive, 114 lungs (2.1 %) were positive for pseudorabies virus and 263 (4.85 %) were positive for classical swine fever virus; much lower than positive for PRRSV (15.1 %, p = 0.023) and PCV2 (13.8 %, p = 0.038). lungs that were positive for PRRSV and/or PCV-2 have significantly increased odds of being positive for any of the S. suis (9.79 vs. 0.44 %, p = 0.003). 相似文献
969.
970.
Bin Wu Alys Peisley Claire Richards Hui Yao Xiaohui Zeng Cecilie Lin Feixia Chu Thomas Walz Sun Hur 《Cell》2013,152(1-2):276-289
Highlights? MDA5 forms an open, C-shaped ring around the viral dsRNA stem ? The CTD of MDA5 has a different orientation and flexibility compared to RIG-I ? MDA5 forms filaments by stacking monomers head-to-tail with a 70° turn per monomer ? The 2CARD domain assembles into oligomers that activate interferon signaling via MAVS 相似文献