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31.
We examined the genomic organization of Hox genes in rainbow trout (Oncorhynchus mykiss), a tetraploid teleost derivative species, in order to test models of presumptive genomic duplications during vertebrate evolution. Thirteen putative clusters were localized in the current rainbow trout genetic map; however, analysis of the sequence data suggests the presence of at least 14 Hox clusters. Many duplicated genes appear to have been retained in the genome and share a high percentage of amino acid similarity with one another. We characterized two Hox genes located within the HoxCb cluster that may have been lost independently in other teleost species studied to date. Finally, we identified conserved syntenic blocks between salmonids and human, and provide data supporting two new linkage group homeologies (i.e., RT-3/16, RT-12/29) and three previously described homeologies (RT-2/9, RT-17/22, and RT-27/31) in rainbow trout. Electronic Supplementary Material Electronic Supplementary material is available for this article at and accessible for authorised users. The sequence data for this study have been submitted to GenBank under the following accession numbers: AY567792, AY567793, AY567794, AY567795, AY567796, AY567797, AY567798, AY567799, AY567800, AY567801, AY567802, AY567803, AY567804, AY567805, AY567806, AY567807, AY567808, AY567809, AY567810, AY567812, AY567813, AY567814, AY567815, AY567816, and AY567817. [Reviewing Editor : Dr. Axel Meyer]  相似文献   
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The Tsimane of lowland Bolivia are an indigenous forager-farmer population living under conditions resembling pre-industrial European populations, with high infectious morbidity, high infection and inflammation, and shortened life expectancy. Analysis of 917 persons ages 5 to 60+ showed that allele frequencies of 9 SNPs examined in the apolipoprotein E (apoE), C-reactive protein (CRP), and interleukin-6 (IL-6) genes differed from some European, African, and north Asian-derived populations. The apoE2 allele was absent, whereas four SNPs related to CRP and IL-6 were monomorphic: CRP (rs1800947, rs3093061, and rs3093062) and IL-6 (rs1800795). No significant differences in apoE, CRP, and IL-6 variants across age were found CRP levels were higher in carriers of two CRP proinflammatory SNPs, whereas they were lower in carriers of apoE4. Taken together the evidence for (1) different allele frequencies between the Tsimane and other populations and (2) the correlations of CRP and apoE alleles with blood CRP may suggest that these variants are under selection in response to a high infection environment.  相似文献   
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Background

Patients with multiple sclerosis (MS) are at increased risk of osteoporosis and fractures. Adipose tissue-derived adipokines may play important roles in the osteoimmunology of MS. In order to determine whether omentin-1 and vaspin may be related to bone health in MS patients, we compared circulating levels of these recently identified adipokines, between MS patients and healthy controls.

Methods

A total of 35 ambulatory MS patients with relapsing-remitting courses were compared with 38 age- and sex-matched healthy controls. Bone mineral density (BMD) was determined for the lumbar spine (L2–L4) and the proximal femur using dual-energy x-ray absorptiometry. Circulating omentin-1, vaspin, osteocalcin, osteopontin, osteoprotegerin, the receptor activator of nuclear factor-κB ligand, matrix metalloproteinase 9, C-reactive protein and 25-hydroxy vitamin D levels were evaluated by highly specific enzyme-linked immunosorbent assay methods.

Results

There was no significant difference between the two groups regarding bone-related cytokines, adipocytokines, and the BMD measurements of patients with MS and the healthy controls. However, in multiple regression analysis, serum omentin-1 levels were positively correlated with BMD at the femoral neck (β = 0.49, p = 0.016), total hip (β = 0.42, p = 0.035), osteopontin (β = 0.42, p = 0.030) and osteocalcin (β = 0.53, p = 0.004) in MS patients. No correlations were found between vaspin, biochemical, and BMD measures in both groups.

Conclusions

Elevated omentin-1 serum levels are correlated with BMD at the femoral neck and the serum levels of osteocalcin and osteopontin in MS patients. Therefore, there is crosstalk between adipose tissue and bone in MS.  相似文献   
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Ficus benjamina, commonly known as weeping fig, Benjamin’s fig or Ficus tree is a species of flowering plant in the family of Moraceae. It is native to south and south-east Asia and Australia. Crown gall tumours were collected from branches of one-year-old weeping fig (F. benjamina L.) trees. A total of 50 strains of Agrobacterium tumefaciens were isolated from diseased Ficus plants and their morphological, molecular and biochemical characteristics were studied; pathogenicity tests on tomato, F. benjamina and Bryophyllum daigremontianum were also conducted. Based on the biochemical characteristics, pathogenicity test and PCR amplification of 730?bp fragment using VCR\VCF primers, the tested bacterial strains were identified as A. tumefaciens. This is the first report of crown gall on F. benjamina in Isfahan and Fars provinces of Iran.  相似文献   
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As part of the effort to find better cellulases for bioethanol production processes, we were looking for novel GH-7 family cellobiohydrolases, which would be particularly active on insoluble polymeric substrates and participate in the rate-limiting step in the hydrolysis of cellulose. The enzymatic properties were studied and are reported here for family 7 cellobiohydrolases from the thermophilic fungi Acremonium thermophilum, Thermoascus aurantiacus, and Chaetomium thermophilum. The Trichoderma reesei Cel7A enzyme was used as a reference in the experiments. As the native T. aurantiacus Cel7A has no carbohydrate-binding module (CBM), recombinant proteins having the CBM from either the C. thermophilum Cel7A or the T. reesei Cel7A were also constructed. All these novel acidic cellobiohydrolases were more thermostable (by 4-10 degrees C) and more active (two- to fourfold) in hydrolysis of microcrystalline cellulose (Avicel) at 45 degrees C than T. reesei Cel7A. The C. thermophilum Cel7A showed the highest specific activity and temperature optimum when measured on soluble substrates. The most effective enzyme for Avicel hydrolysis at 70 degrees C, however, was the 2-module version of the T. aurantiacus Cel7A, which was also relatively weakly inhibited by cellobiose. These results are discussed from the structural point of view based on the three-dimensional homology models of these enzymes.  相似文献   
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Recent human genetic studies suggest that allelic variants of leukotriene pathway genes influence the risk of clinical and subclinical atherosclerosis. We sequenced the promoter, exonic, and splice site regions of ALOX5 and ALOX5AP and then genotyped 7 SNPs in ALOX5 and 6 SNPs in ALOX5AP in 1,552 cases with clinically significant coronary artery disease (CAD) and 1,583 controls from Kaiser Permanente including a subset of participants of the coronary artery risk development in young adults study. A nominally significant association was detected between a promoter SNP in ALOX5 (rs12762303) and CAD in our subset of white/European subjects (adjusted odds ratio per minor allele, log-additive model, 1.32; P = 0.002). In this race/ethnic group, rs12762303 has a minor allele frequency of 15% and is tightly linked to variation at the SP1 variable tandem repeat promoter polymorphism. However, the association between CAD and rs12762303 could not be reproduced in the atherosclerosis risk in communities study (hazard rate ratio per minor allele; 1.08, P = 0.1). Assuming a recessive mode of inheritance, the association was not significant in either population study but our power to detect modest effects was limited. No significant associations were observed between all other SNPs and the risk of CAD. Overall, our findings do not support a link between common allelic variation in or near ALOX5 or ALOX5AP and the risk of CAD. However, additional studies are needed to exclude modest effects of promoter variation in ALOX5 on the risk of CAD assuming a recessive mode of inheritance. Themistocles L. Assimes and Joshua W. Knowles contributed equally to this work.  相似文献   
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Peroxidase is one of the most widely used enzymes in biotechnology and medicine. In the current study, cDNA encoding peroxidase from Lepidium draba (LDP) was cloned and expressed in Escherichia coli BL21 (DE3) cells in the form of inclusion bodies (IBs). To achieve purified active enzyme, IBs were solubilized before being purified and refolded. The deduced amino acid sequence (308) of the LDP gene (924 bp) revealed 88.96% identity to horseradish peroxidase C1A (HRP C1A). The results of basic local alignment search tool (BLAST) and phylogenetic analysis of the protein sequence showed that this enzyme belongs to the neutral group of class III plant peroxidases. According to sequence analysis and structural modeling, critical amino acids in heme and calcium binding domain as well as cysteine residues were conserved as HRP C1A except for calcium binding domain where valine228 was replaced with isoleucine. The far-UV circular dichroism (CD) results were confirmed by homology modeling data showing the enzyme consists mainly of α-helices as other plant peroxidases. Overall, according to the results of catalytic activity and refolding yield, LDP can be introduced as a novel peroxidase for medical and biotechnology applications.  相似文献   
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