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991.
Remarkable genetic diversity detected at river buffalo prolactin receptor (PRLR) gene and association studies with milk fatty acid composition 下载免费PDF全文
G. Cosenza M. Iannaccone B. Auzino N. P. P. Macciotta A. Kovitvadhi I. Nicolae A. Pauciullo 《Animal genetics》2018,49(3):159-168
Prolactin is an anterior pituitary peptide hormone involved in many different endocrine activities and is essential for reproductive performance. This action is mediated by its receptor, the prolactin receptor, encoded by the PRLR gene. In this study, we sequenced and characterized the Mediterranean river buffalo PRLR gene (from exon 3 to 10), and we found remarkable genetic diversity. In particular, we found 24 intronic polymorphisms and 13 exonic SNPs, seven of which were non‐synonymous. Furthermore, the polymorphisms identified in the 3′‐UTR were investigated to establish their possible influence on microRNA binding sites. Considering all the amino acid changes and the observed allelic combinations, it is possible to deduce at least six different translations of the buffalo prolactin receptor and, consequently, the presence at the PRLR gene of at least six alleles. Furthermore, we identified a deletion of a CACTACC heptamer between nucleotides 1102 and 1103 of exon 10 (3′‐UTR), and we developed an allele‐specific PCR to identify the carriers of this genetic marker. Finally, the SNP g.11188A>G, detected in exon 10 and responsible for the amino acid replacement p.His328Arg, was genotyped in 308 Italian Mediterranean river buffaloes, and an association study with milk fat traits was carried out. The statistical analysis showed a tendency that approached significance for the AA genotype with higher contents of odd branched‐chain fatty acids. Thus, our results suggest that the PRLR gene is a good candidate for gene association studies with qualitative traits related to buffalo milk production. 相似文献
992.
Biophysics - A method was proposed for multi-exponential approximation of the fluorescence decay kinetics. Unlike the well-known Prony technique, the method is suitable for analyzing large-scale... 相似文献
993.
994.
Staphylococci from Sheedal of Northeast India was isolated, identified and characterized. All the isolated staphylococci were found to be coagulase negative. Based on the rpoB gene sequences followed by analysis using NCBI-BLAST software, seven species of Staphylococcus namely, S. piscifermentans, S. condimenti, S. arlettae, S. sciuri, S. warneri, S. nepalensis and S. hominis were recognized. Phylogenetic analyses revealed three major cluster groups. All the seven Staphylococcus showed their NaCl tolerance from 2 to 8%. No species was able to grow at 55°C. Except S. arlettae and S. sciuri, all the isolated staphylococcal species exhibited growth at pH 4–8. No isolated species was able to ferment mannitol, sucrose and arabinose. All the species exhibited moderate to maximum proteolytic and lipolytic activities. All the seven species were found to be sensitive to the antibiotics, namely, erythromycin, norfloxacin, ampicillin, streptomycin and vancomycin, whereas all were resistant to co-trimoxazole. Only S. piscifermentans was found antagonist to Salmonella enterica, Escherichia coli and Bacillus subtilis, although the clear zone was minimal. All the staphylococcal species except S. arlettae and S. sciuri exhibited hydrophobicity ranging from 25 to 66%. The observed characteristics of isolated Staphylococci from Sheedal revealed their role in fish fermentation. 相似文献
995.
Risks and benefit evaluation for controlled human infection studies, where healthy volunteers are deliberately exposed to infectious agents to evaluate vaccine efficacy, should be explicit, systematic, thorough, and non-arbitrary. Decision analysis promotes these qualities using four steps: (1) determining explicit criteria and measures for evaluation, (2) identifying alternatives to the study, (3) defining the models used to estimate the measures for each alternative, and (4) running the models to produce the estimates and compare the alternatives. In this paper, we describe how decision analysis might be applied by funders and regulators, as well as by others contemplating the use of novel controlled human infection studies for vaccine development and evaluation. 相似文献
996.
V. A. Ryabov 《Biophysics》2014,59(1):135-147
Two-channel recording of acoustic signals from two quasi-stationary dolphins has previously suggested that the dolphin echolocation system is more complex than discussed earlier, and includes at least four sonars. In the present work, two-channel recording of signals, analysis and interpretation of their functions were continued in terms of physical acoustics, signal theory and echolocation. The results indicate that the echolocation system of dolphins involves four organs to produce probing signals of five different types, which implies different mechanisms of their processing by the dolphin hearing; its operation corresponds to as many as six varieties of sonar systems. The results are of importance for studying the echolocation system of Odontoceti and for improving sonars and radars. 相似文献
997.
In the experiments on redox potential measurement for a series of identical samples of purified and presettled water it was found that the response to ultraviolet irradiation varies appreciably within a few days after treatment, including stepwise changes. In a few hours after exposure, leading to a higher content of reactive oxygen species as compared with the equilibrium values, long-term changes including variations in redox potential and optical system parameters are recorded in water and diluted aqueous media. We propose a heuristic organization model of the water-gas system with an increased content of reactive oxygen species. 相似文献
998.
Zhanyuan J. Zhang 《Planta》2014,239(6):1139-1146
Completion of whole genome sequencing in many plant species including economically important crop species not only opens up new opportunities but also imposes challenges for plant science research community. Functional validation and utilization of these enormous DNA sequences necessitate new or improved tools with high accuracy and efficiency. Of various tools, small RNA-mediated gene silencing platform plays an important and unique role in functional verification of plant genes and trait improvements. Artificial trans-acting small interfering RNA (atasiRNA) has emerged as a potent and specific gene silencing platform which overcomes major limitations of other small RNA silencing approaches including double-stranded RNA, artificial microRNA (amiRNA), and microRNA-induced gene silencing. To best utilize atasiRNA platform, it is essential to be able to test candidate atasiRNAs efficiently through either in vivo or in vitro validation approach. Very recently, a breakthrough has been made in developing a new method for in vitro screen of amiRNA candidates, named “epitope-tagged protein-based amiRNA screens”. Such a screen can be readily employed to validate atasiRNA candidates and thus accelerate the deployment of atasiRNA technology. Therefore, atasiRNA as an emerging tool shall accelerate both plant biology study and crop genetic improvements including trait stacking. 相似文献
999.
A. M. Prokofiev 《Journal of Ichthyology》2014,54(8):493-500
This paper provides an overview of the family Bathyclupeidae of the world fauna; the geographic and bathymetric distribution of species is updated. It is concluded that the family includes nine species that are grouped into two genera—Bathyclupea Alcock and Neobathyclupea gen. nov. The new genus differs from the type one by the development of black pigment in the orobranchial cavity, smooth ventral branch of preoperculum, developed last pair of pleural ribs, and the number of rays in the vertical fins. 相似文献
1000.