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991.
Tian X.L. Cao L.X. Tan H.M. Zeng Q.G. Jia Y.Y. Han W.Q. Zhou S.N. 《World journal of microbiology & biotechnology》2004,20(3):303-309
The populations of endophytic fungi and actinomycetes from four rice cultivars in the Panyu district (Site 1) and Wushan district
(Site 2) in Guangdong province, South China, were studied. The preponderant endophytic fungi and actinomycetes isolated belonged
to Fusarium and Streptomyces respectively. The incidence of Streptomycetes griseofuscus ranged from 36.1 to 69% out of all the different rice cultivars from the two sites. It is the commonest population of endophytic
actinomycetes, and constituted the greatest part of all the antagonistic communities. The distributions of endophytic fungi
and actinomycetes in roots and leaves were different, endophytic fungi from leaves were diverse, some were organ-specific.
More diverse endophytic actinomycetes were isolated from roots than from leaves. The endophytic fungi isolated from rice in
Site 2 were more diverse than that in Site 1. The diversity of the endophytic actinomycetes, however, was less than that in
Site 1. Acid soil in Site 2 is ideal for the growth and colonization of fungi while the alkaline soil in Site 1 is better
for the growth and colonization of actinomycetes. The results suggested that differences in the chemical composition of soil
could influence the endophytic microbial communities of rice plants. The endophytic fungi and actinomycetes isolated from
poor-growing seedlings and susceptible rice cultivars were more abundant than that the disease-resistant counterparts. In
the dual culture and activity detection of the metabolites, 41.2% of all the isolated endophytic fungi showed antagonism to
rice pathogens. Fifty percent of all the isolated endophytic actinomycetes were antagonistic to those pathogens. The percentage
of Streptomyces griseofuscus and hygroscopicus reached 55.4 and 21.4% of all the active actinomycetes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
992.
993.
[目的]利用分子生物学手段探索裳卷蛾变形孢虫的遗传发育地位.[方法]微孢子虫的SSUrRNA序列是构建系统发育进化树的重要工具.试验通过T-A克隆法对裳卷蛾变形孢虫(Vairimorphaceraces)SSU rRNA核心序列进行了克隆,并采用近邻法构建了系统发育进化树.[结果]克隆得到了长为1228bp的核苷酸序列(GenBank EU267796).系统发育分析结果表明:裳卷蛾变形孢虫与分离于小菜蛾(Plutella xylostella)的Vairimorpha sp.Germany(GenBank AF124331)和Vairimorphaimperyecta(GenBank AJ131645)相似性最高,它们在系统发育进化树中与寄主为鳞翅目昆虫的Nosema属聚为一类,与纳卡变形孢虫(Vairimorpha necatrix)为代表的Vairimorpha属为相邻集.[结论]结合其生物学特征,裳卷蛾变形孢虫确实为Vairimorph a属的成员,但根据系统发育分析归入Nosematidae科可能更为合适. 相似文献
994.
995.
Canuel M Lefrancois S Zeng J Morales CR 《Biochemical and biophysical research communications》2008,366(3):724-730
Sortilin has been implicated in the sorting of one soluble hydrolase and two sphingolipid activator proteins to the lysosomes. While the GGA adaptor proteins have been demonstrated to play a role in the targeting of sortilin to the endosomes, the recycling of sortilin has not yet been elucidated. Here we examine the role of two adaptor protein complexes, AP-1 and retromer. Our results demonstrate that AP-1 is required for the transport of sortilin to the endosomes and retromer for the recycling of sortilin to the Golgi apparatus. While inhibition of AP-1 causes accumulation of sortilin in the Golgi apparatus, RNAi depletion of retromer results in retention of sortilin in the lysosomes. We also demonstrate that the interaction of sortilin with retromer occurs through a YXXΦ site in its cytosolic tail. In conclusion, our observations indicate that retromer and AP-1 play opposite roles in the trafficking of sortilin. 相似文献
996.
Zeng R Zhang Z Mei X Gong W Wei L 《Biochemical and biophysical research communications》2008,377(2):495-499
Respiratory syncytial virus (RSV) is a major respiratory pathogen in newborns. Neonate vaccine should induce strong protective immunity. We have engineered a subunit vaccine candidate G1F/M2. A major problem in developing subunit vaccines is their limited immunogenicity. Aluminium adjuvants with a long history of use with routine childhood vaccines have some limitations, especially inability to elicit CTL response. There is a need for alternative adjuvants. Heat shock proteins (HSPs) are characterized as potent immunoadjuvants. In this study, HSP70-like protein 1 (HSP70L1) gene was cloned. The recombinant protein HSP70L1 was expressed in E. coli, purified and renaturated. We evaluated the potential of HSP70L1 used as the adjuvant of G1F/M2. G1F/M2 was chemically cross-linked with HSP70L1 (HSP-G1F/M2). HSP70L1 enhanced significantly the immunogenicity and protective effect of G1F/M2. HSP-G1F/M2 induced significant higher levels of antibodies, neutralizing antibodies and CTL activity than unadjuvanted G1F/M2. The antibody titers induced by HSP-G1F/M2 were similar to that by G1F/M2 + Alum. RSV-specific CTL activity induced by HSP-G1F/M2 was stronger than that by G1F/M2 + Alum. Interestingly, the protective effect of HSP-G1F/M2 against RSV was significantly stronger than that of G1F/M2 + Alum. The results suggest that HSP70L1 is a potent adjuvant of G1F/M2. 相似文献
997.
芝麻素散剂调血脂作用研究 总被引:4,自引:0,他引:4
目的:观察芝麻素散剂对实验性高脂血症大鼠血脂的影响。方法:在给大鼠喂以高脂饲料的同时灌胃芝麻素散剂14天后测定血清总胆固醇(TC)、甘油三酯(TG)和高密度脂蛋白胆固醇(LDL-C)水平。结果:芝麻素散剂明显抑制TC、LDL-C的升高。结论:芝麻素散剂对大鼠实验性高脂血症有显著的预防作用。 相似文献
998.
Polyploidy has been recognized as an important step in the evolutionary diversification of flowering plants and may have a significant impact on plant breeding. Statistical analyses for linkage mapping in polyploid species can be difficult due to considerable complexities in polysomic inheritance. In this article, we develop a novel statistical method for linkage analysis of polymorphic markers in a full-sib family of autotetraploids. This method is established on multivalent pairings of homologous chromosomes at meiosis and can provide a simultaneous maximum-likelihood estimation of the double reduction frequencies of and recombination fraction between two markers. The EM algorithm is implemented to provide a tractable way for estimating relative proportions of different modes of gamete formation that generate identical gamete genotypes due to multivalent pairings. Extensive simulation studies were performed to demonstrate the statistical properties of this method. The implications of the new method for understanding the genome structure and organization of polyploid species are discussed. 相似文献
999.
PGRL is a major CD81-associated protein on lymphocytes and distinguishes a new family of cell surface proteins. 总被引:7,自引:0,他引:7
K L Clark Z Zeng A L Langford S M Bowen S C Todd 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(9):5115-5121
CD81 exerts a range of interesting effects on T cells including early thymocyte differentiation, LFA-1 activation, and provision of costimulation. To better understand the mechanisms by which CD81 influences T cell function we evaluated CD81 molecular complexes on T cells. The most prominent CD81-associated cell surface protein on thymocytes as well as a number of T cell and B cell lines has an apparent molecular mass of 75 kDa. The 75-kDa protein was purified and analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry followed by postsource-decay profiling. p75 is a novel type I transmembrane protein of the Ig superfamily which is most similar to FPRP. We cloned and sequenced both human and mouse PG regulatory-like protein (PGRL) and characterized mouse PGRL expression in both lymphocytes and nonlymphoid tissues. The discovery of PGRL allows for the clustering of a small family of related proteins including PGRL, FPRP, V7/CD101, and IGSF3. Expression constructs containing various domains of PGRL with an epitope tag were coexpressed with CD81 and used to determine that the interaction of CD81 with PGRL requires the membrane distal Ig3-Ig4 domains of PGRL. Although it remains to be determined whether PGRL possesses PG regulatory functions, transwell chamber experiments show that PGs and CD81 coordinately regulate T cell motility. 相似文献
1000.
Protection against Tetanus by Needle-Free Inoculation of Adenovirus-Vectored Nasal and Epicutaneous Vaccines 下载免费PDF全文
Zhongkai Shi Mingtao Zeng Guang Yang Felix Siegel Laura J. Cain Kent R. van Kampen Craig A. Elmets De-Chu C. Tang 《Journal of virology》2001,75(23):11474-11482
The effectiveness of vaccination programs would be enhanced greatly through the availability of vaccines that can be administered simply and, preferably, painlessly without the need for timed booster injections. Tetanus is a prime example of a disease that is readily preventable by vaccination but remains a major threat to public health due to the problems associated with administration of the present vaccine. Here we show that a protective immune response against live Clostridium tetani infection in mice can be elicited by an adenovirus vector encoding the tetanus toxin C fragment when administered as a nasal or epicutaneous vaccine. The results suggest that these vaccination modalities would be effective needle-free alternatives. This is the first demonstration that absorption of a small number of vectored vaccines into the skin following topical application of a patch can provide protection against live bacteria in a disease setting. 相似文献