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161.
Mort M Convey I Baxter J Bailey C 《Journal of applied animal welfare science : JAAWS》2008,11(2):133-148
The 2001 UK foot and mouth disease (FMD) crisis is commonly understood to have been a nonhuman animal problem, an economic industrial crisis that was resolved after eradication. By using a different lens, a longitudinal ethnographic study of the health and social consequences of the epidemic, the research reported here indicates that 2001 was a human tragedy as well as an animal one. In a diary-based study, it can be seen that life after the FMD crisis was accompanied by distress, feelings of bereavement, fear of a new disaster, loss of trust in authority and systems of control, and the undermining of the value of local knowledge. Diverse groups experienced distress well beyond the farming community. Such distress remained largely invisible to the range of “official” inquiries into the disaster. That an FMD epidemic of the scale of 2001 could happen again in a developed country is a deeply worrying prospect, but it is to be hoped that contingency plans are evolving along with enhanced understanding of the human, animal, and financial cost. 相似文献
162.
Protein quality and stability are critical during protein purification for X-ray crystallography. A target protein that is easy to manipulate and crystallize becomes a valuable product useful for high-throughput crystallography for drug design and discovery. In this work, a single surface mutation, D355R, was shown to be crucial for converting the modestly stable monomeric ligand binding domain of the human thyroid hormone receptor (TR LBD) into a stable dimer. The structure of D335R TR LBD mutant was solved using X-ray crystallography and refined to 2.2 A resolution with R(free)/R values of 24.5/21.7. The crystal asymmetric unit reveals the TR dimer with two molecules of the hormone-bound LBD related by twofold symmetry. The ionic interface between the two LBDs comprises residues within loop H10-H11 and loop H6-H7 as well as the C-terminal halves of helices 8 of both protomers. Direct intermolecular contacts formed between the introduced residue Arg 355 of one TR molecule and Glu 324 of the second molecule become a part of the extended dimerization interface of 1330 A(2) characteristic for a strong complex assembly that is additionally strengthened by buffer solutes. 相似文献
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Mimicry has had a significant historical influence as a tractable system for studying adaptation and is known to play a role in speciation. Here, we discuss recent theoretical treatment of adaptive walks to local adaptive peaks and contrast this with the adaptive landscape of mimicry. Evolution of novel Müllerian mimicry patterns almost certainly involves substitution of a major mutation to provide an initial similarity to the model, such that major gene effects are expected to an even greater degree than for other adaptive traits. The likelihood of large adaptive peak shifts in mimicry evolution may therefore promote speciation. In addition, mimicry adaptive peaks are determined by the local abundance of particular patterns and may be more fluid than the case for other traits. It will therefore be of considerable interest to test empirically the distribution of effect sizes fixed during mimicry evolution. Here, we show the feasibility of this by presenting a preliminary quantitative trait locus (QTL) analysis of Heliconius colour patterns. This shows that a number of modifier loci of different effect sizes influence forewing band morphology. We also show multiple pleiotropic effects of major Heliconius patterning loci and discuss the likelihood of multiple substitutions at the same loci in pattern evolution, which would inflate the importance of major loci in QTL analysis of the gene effect sizes. Analyses such as these have the potential to uncover the genetic architecture of both within and between species adaptive differences. 相似文献
167.
Gpnmb is a melanoblast-expressed, MITF-dependent gene 总被引:1,自引:0,他引:1
168.
Loksum Wong Cameron J Weadick Claire Kuo Belinda SW Chang Vincent Tropepe 《BMC developmental biology》2010,10(1):100
Background
The Dmbx1 gene is important for the development of the midbrain and hindbrain, and mouse gene targeting experiments reveal that this gene is required for mediating postnatal and adult feeding behaviours. A single Dmbx1 gene exists in terrestrial vertebrate genomes, while teleost genomes have at least two paralogs. We compared the loss of function of the zebrafish dmbx1a and dmbx1b genes in order to gain insight into the molecular mechanism by which dmbx1 regulates neurogenesis, and to begin to understand why these duplicate genes have been retained in the zebrafish genome. 相似文献169.
Elizabeth Buescher Tilman Achberger Idris Amusan Anthony Giannini Cherie Ochsenfeld Ana Rus Brett Lahner Owen Hoekenga Elena Yakubova Jeffrey F. Harper Mary Lou Guerinot Min Zhang David E. Salt Ivan R. Baxter 《PloS one》2010,5(6)
Controlling elemental composition is critical for plant growth and development as well as the nutrition of humans who utilize plants for food. Uncovering the genetic architecture underlying mineral ion homeostasis in plants is a critical first step towards understanding the biochemical networks that regulate a plant''s elemental composition (ionome). Natural accessions of Arabidopsis thaliana provide a rich source of genetic diversity that leads to phenotypic differences. We analyzed the concentrations of 17 different elements in 12 A. thaliana accessions and three recombinant inbred line (RIL) populations grown in several different environments using high-throughput inductively coupled plasma- mass spectroscopy (ICP-MS). Significant differences were detected between the accessions for most elements and we identified over a hundred QTLs for elemental accumulation in the RIL populations. Altering the environment the plants were grown in had a strong effect on the correlations between different elements and the QTLs controlling elemental accumulation. All ionomic data presented is publicly available at www.ionomicshub.org. 相似文献
170.
M J Slater S Cockerill R Baxter R W Bonser K Gohil C Gowrie J E Robinson E Littler N Parry R Randall W Snowden 《Bioorganic & medicinal chemistry》1999,7(6):1067-1074
In our search for new, safer anti-HCMV agents, we discovered that the natural product Arcyriaflavin A (la) was a potent inhibitor of HCMV replication in cell culture. A series of analogues (symmetrical indolocarbazoles) was synthesised to investigate structure activity relationships in this series against a range of herpes viruses (HCMV, VZV, HSV1, and 2). This identified a number of novel, selective and potent inhibitors of HCMV, 12,13-dihydro-2,10-difluoro-5H-indolo[2,3-a]pyrrolo[3,4-c]carbazol e-5,7-(6H)-dione (1d) being the best example (IC50=40 nM, therapeutic index > 1450). Compounds described in this series were generally poor inhibitors of protein kinase C betaII, and no correlation was found between the ability to inhibit HCMV and the enzyme PKC. 相似文献