Tissue distribution and evolution of fructosamine 3-kinase and fructosamine 3-kinase-related protein

Fructosamine 3-kinase (FN3K) and FN3K-related protein (FN3K-RP) catalyze the phosphorylation of the Amadori products ribulosamines, psicosamines, and, in the case of FN3K, fructosamines. BLAST searches in chordate genomes revealed two genes encoding proteins homologous to FN3K or FN3K-RP in various mammals and in chicken but only one gene, encoding a protein more similar to FN3K-RP than to FN3K, in fishes and the sea squirt Ciona intestinalis. This suggests that a gene duplication event occurred after the fish radiation and that the FN3K gene evolved more rapidly than the FN3K-RP gene. In agreement with this distribution, only one enzyme, phosphorylating ribulosamines and psicosamines but not fructosamines, was found in the tissues from a fish (Clarias gariepinus), whereas two enzymes with specificities similar to either FN3K or FN3K-RP were found in mouse, rat, and chicken tissues. FN3K is particularly active in brain, heart, kidney, and skeletal muscle. Its activity is also relatively elevated in erythrocytes from man, rat, and mouse but barely detectable in erythrocytes from chicken and pig, which correlates well with the low intracellular concentration of glucose in erythrocytes from these species. This is in keeping with the specific role of FN3K to repair protein damage caused by glucose. FN3K-RP was more evenly distributed in tissues, except for skeletal muscle where its activity was particularly low. This may be related to low activity of the pentose phosphate pathway in this tissue, as suggested by assays of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. This finding, together with the high affinity of FN3K-RP for ribulosamines, suggests that this enzyme may serve to repair damage caused by the powerful glycating agent, ribose 5-phosphate.     

Hormone-sensitive lipase-independent adipocyte lipolysis during beta-adrenergic stimulation, fasting, and dietary fat loading

In white adipose tissue, lipolysis can occur by hormone-sensitive lipase (HSL)-dependent or HSL-independent pathways. To study HSL-independent lipolysis, we placed HSL-deficient mice in conditions of increased fatty acid flux: beta-adrenergic stimulation, fasting, and dietary fat loading. Intraperitoneal administration of the beta(3)-adrenergic agonist CL-316243 caused a greater increase in nonesterified fatty acid level in controls (0.33 +/- 0.05 mmol/l) than in HSL(-/-) mice (0.12 +/- 0.01 mmol/l, P < 0.01). Similarly, in isolated adipocytes, lipolytic response to CL-316243 was greatly reduced in HSL(-/-) mice compared with controls. Fasting for 相似文献   

Activated vitronectin as a target for anticancer therapy with human antibodies

The formation of a provisional extracellular matrix represents an important step during tumor growth and angiogenesis. Proteins that participate in this process become activated and undergo conformational changes that expose biologically active cryptic sites. Activated matrix proteins express epitopes not found on their native counterparts. We hypothesized that these epitopes may have a restricted tissue distribution, rendering them suitable targets for therapeutic human monoclonal antibodies (huMabs). In this study, we exploited phage antibody display technology and subtractive phage selection to generate human monoclonal antibody fragments that discriminate between the activated and native conformation of the extracellular matrix protein vitronectin. One of the selected antibody fragments, scFv VN18, was used to construct a fully human IgG/ monoclonal antibody with an affinity of 9.3 nM. In immunohistochemical analysis, scFv and huMab VN18 recognized activated vitronectin in tumor tissues, whereas hardly any activated vitronectin was detectable in normal tissues. Iodine 123–radiolabeled huMabVN18 was shown to target to Rous sarcoma virus-induced tumors in chickens, an animal model in which the epitope for huMab VN18 is exposed during tumor development. Our results establish activated vitronectin as a potential target for tumor therapy in humans.Supported in part by the Dutch Cancer Society (grant UU1999-2114) and the Vanderes Foundation, The Hague, The Netherlands.     

Genetic diversity patterns in the SR-BI/II locus can be explained by a recent selective sweep

The human scavenger receptor class B type I (SR-BI and splice variant SR-BII) plays a central role in HDL cholesterol metabolism and represents a candidate gene for a number of related diseases. We examined the genetic diversity of its coding and flanking regions in a sample of 178 chromosomes from individuals of European, African, East Asian (including Southeast Asian), Middle-Eastern as well as Amerindian descent. Nine of the 14 polymorphisms observed are new. Four of the five variants causing amino acid replacements, G2S, S229G, R484W, and G499R, are likely to affect protein structure and function. SR-BI/BII diversity is partitioned among 19 haplotypes; all but one interconnected by single mutation or a recombination event. Such tight haplotype network and the unusual geographic partitioning of this diversity, high not only in Africa but in East Asia as well, suggests its recent origin and possible effect of selection. Coalescent analysis infers a relatively short time to the most recent common ancestor and points to population expansion in Africa and East Asia. These two continents differ significantly in pairwise F(ST) values, differing as well from a single cluster formed by Europe, Middle East and America. In the context of findings for similarly analyzed other loci, we propose that a selective sweep at the origin of modern human populations could explain the low level of ancestral SR-BI/II diversity. The unusually deep split between Africa and Asia, well beyond the Upper Paleolithic when inferred under neutrality, is consistent with subsequent geographical and demographic expansion favoring the accumulation of new variants, especially in groups characterized by large effective population sizes, such as Asians and Africans. The relevance of such partitioning of SR-BI/II diversity remains to be investigated in genetic epidemiological studies which can be guided by the present findings.     

Local responses to conservation in the Richtersveld National Park, South Africa

Local notions of conservation deserve closer scrutiny. We cannot assume that they naturally coincide with those of the tourist core; nor that they are automatically given higher priority when local populations are induced to participate in practices which conserve flora and fauna. A case study of the establishment of the Richtersveld National Park in Namaqualand, a remote arid region of South Africa, is used to argue that local attitudes to conservation and development (associated with tourism) can become increasingly cynical and ambivalent in the context of ecotourism. Furthermore, such attitudes are shaped less by economic inducements than by the often contradictory messages about conservation that are being communicated daily.     

3D‐liquid chromatography as a complex mixture characterization tool for knowledge‐based downstream process development

Knowledge‐based development of chromatographic separation processes requires efficient techniques to determine the physicochemical properties of the product and the impurities to be removed. These characterization techniques are usually divided into approaches that determine molecular properties, such as charge, hydrophobicity and size, or molecular interactions with auxiliary materials, commonly in the form of adsorption isotherms. In this study we demonstrate the application of a three‐dimensional liquid chromatography approach to a clarified cell homogenate containing a therapeutic enzyme. Each separation dimension determines a molecular property relevant to the chromatographic behavior of each component. Matching of the peaks across the different separation dimensions and against a high‐resolution reference chromatogram allows to assign the determined parameters to pseudo‐components, allowing to determine the most promising technique for the removal of each impurity. More detailed process design using mechanistic models requires isotherm parameters. For this purpose, the second dimension consists of multiple linear gradient separations on columns in a high‐throughput screening compatible format, that allow regression of isotherm parameters with an average standard error of 8%. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1283–1291, 2016     

Crop rotation associating a legume and the nickel hyperaccumulator <Emphasis Type="Italic">Alyssum murale</Emphasis> improves the structure and biofunctioning of an ultramafic soil

Nickel (Ni) agromining aims to phytoextract heavy metals using hyperaccumulators whilst at the same time rehabilitating ultramafic soils. After removing the bioavailable metal, ultramafic soils are improved in terms of their agronomic properties with the aim of future agricultural uses. The low fertility of ultramafic soils can be compensated by integrating legumes already used in traditional agro-systems because of their importance in soil nitrogen enrichment. However, few studies have evaluated the potential profits of legumes on Ni agromining and their potential benefits on soil biological fertility. Here, we characterized the effect of a crop rotation with two plants, a legume (Vicia sativa) and a hyperaccumulator (Alyssum murale), on the phytoextraction efficiency and on soil structure and biofunctioning. A pot experiment was set up in controlled conditions to grow A. murale and four treatments were tested: rotation with V. sativa (Ro), fertilized mono-culture (FMo), non-fertilized mono-culture (NFMo) and bare soil without plants (BS). No significant difference was found between the Ro and NFMo treatments for the dry biomass yield. However, the Ro treatment showed the highest Ni concentrations ([Ni]) in A. murale shoots compared to FMo and NFMo treatments. The Ro treatment plants had more than twice as many leaves [Ni] compared to FMo. Soil physico-chemical analyses showed that the Ro treatment was better structured and showed the highest presence of bacterial micro-aggregates, as well as less non-aggregated particles. Legumes integration in Ni-agromining systems could be a pioneering strategy to reduce chemical inputs and to improve soil biofunctioning and thus fertility.