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31.
Global climate change is increasing the frequency of unpredictable weather conditions; however, it remains unclear how species‐level and geographic factors, including body size and latitude, moderate impacts of unusually warm or cool temperatures on disease. Because larger and lower‐latitude hosts generally have slower acclimation times than smaller and higher‐latitude hosts, we hypothesised that their disease susceptibility increases under ‘thermal mismatches’ or differences between baseline climate and the temperature during surveying for disease. Here, we examined how thermal mismatches interact with body size, life stage, habitat, latitude, elevation, phylogeny and International Union for Conservation of Nature (IUCN) conservation status to predict infection prevalence of the chytrid fungus Batrachochytrium dendrobatidis (Bd) in a global analysis of 32 291 amphibian hosts. As hypothesised, we found that the susceptibility of larger hosts and hosts from lower latitudes to Bd was influenced by thermal mismatches. Furthermore, hosts of conservation concern were more susceptible than others following thermal mismatches, suggesting that thermal mismatches might have contributed to recent amphibian declines.  相似文献   
32.
Wetlands Ecology and Management - The unprecedented size of the deepwater horizon oil spill and scope of the subsequent response elicited intense and sustained interest in microbial responses to...  相似文献   
33.
Cyclic nucleotide phosphodiesterase 11A (PDE11A) is the newest member in the PDE family. Although the tissue distribution of PDE11A mRNA has been shown, its protein expression pattern has not been well studied. The goal of this report is to investigate the distribution of PDE11A proteins in a wide range of normal and malignant human tissues. We utilized a polyclonal antibody that recognized all four PDE11A isoforms. Its specificity was demonstrated by Western blot analysis on a recombinant human PDE11A protein and native PDE11A proteins in various human tissues. Immunohistochemistry showed that PDE11A is widely expressed. Various degrees of immunoreactivity were observed in the epithelial cells, endothelial cells, and smooth muscle cells of all tissues examined. The highest expression was in the epithelial, endothelial, and smooth muscle cells of the prostate, Leydig, and spermatogenic cells of the testis, the tubule epithelial cells in the kidney, the epithelial and endothelial cells in the adrenal, the epithelial cells and macrophages in the colon, and the epidermis in the skin. Furthermore, PDE11A expression was also detected in several human carcinomas. Our results suggest that PDE11A might be involved in multiple physiological processes in various organs via its ability to modulate intracellular cAMP and cGMP levels.  相似文献   
34.
The noncanonical Wnt/planar cell polarity (PCP) pathway controls a variety of cell behaviors such as polarized protrusive cell activity, directional cell movement, and oriented cell division and is crucial for the normal development of many tissues. Mutations in the PCP genes cause malformation in multiple organs. Recently, the PCP pathway was shown to control endocytosis of PCP and non-PCP proteins necessary for cell shape remodeling and formation of specific junctional protein complexes. During formation of the renal glomerulus, the glomerular capillary becomes enveloped by highly specialized epithelial cells, podocytes, that display unique architecture and are connected via specialized cell-cell junctions (slit diaphragms) that restrict passage of protein into the urine; podocyte differentiation requires active remodeling of cytoskeleton and junctional protein complexes. We report here that in cultured human podocytes, activation of the PCP pathway significantly stimulates endocytosis of the core slit diaphragm protein, nephrin, via a clathrin/β-arrestin-dependent endocytic route. In contrast, depletion of the PCP protein Vangl2 leads to an increase of nephrin at the cell surface; loss of Vangl2 functions in Looptail mice results in disturbed glomerular maturation. We propose that the PCP pathway contributes to podocyte development by regulating nephrin turnover during junctional remodeling as the cells differentiate.  相似文献   
35.
Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
36.
The anaphase promoting complex/cyclosome (APC/C) is crucial to the control of cell division (for a review, see ref. 1). It is a multi-subunit ubiquitin ligase that, at defined points during mitosis, targets specific proteins for proteasomal degradation. The APC/C is itself regulated by the spindle or kinetochore checkpoint, which has an important role in maintaining genomic stability by preventing sister chromatid separation until all chromosomes are correctly aligned on the mitotic spindle. The spindle checkpoint regulates the APC/C by inactivating Cdc20, an important co-activator of the APC/C. There is also evidence to indicate that the spindle checkpoint components and Cdc20 are spatially regulated by the mitotic apparatus, in particular they are recruited to improperly attached kinetochores. Here, we show that the APC/C itself co-localizes with components of the spindle checkpoint to improperly attached kinetochores. Indeed, we provide evidence that the spindle checkpoint machinery is required to recruit the APC/C to kinetochores. Our data indicate that the APC/C could be regulated directly by the spindle checkpoint.  相似文献   
37.
The red alga Cubiculosporum koronicarpis gen. et sp. nov. is described from material collected during 1968 in the Philippines. The species differs substantially in regard to its carposporophyte development from other red algae in the order Gigartinales, and a new family is created based on its unique combination of reproductive features. A single, short, connecting filament is formed between the fertilized carpogonium and a nearby auxiliary cell. The latter produces several ramifying gonimoblast filaments towards the interior of the thallus. No fusion cell is formed and the gonimoblast filaments grow inward among the cells of the central axis, form secondary connections to them, and give rise to outwardly directed carposporangial filaments that develop within peripheral chambers formed between elongating inner cortical cells. The alga is a low, clump-forming species of well-washed intertidal reef platforms at the one Philippine locality where it has been found. There it contributed a uniform but very minor amount to the wet weight of the standing crops that were studied during two separate seasons of the year.  相似文献   
38.
39.
The specificity of T cells for syngeneic target cells is directed to both antigens and products of the major histocompatibility complex (MHC) on the target cell surface. This dual requirement is best accounted for by the altered-self hypothesis, which implies that the MHC products on a cell's surface are able to form complexes with many other proteins on the surface of the same cell. To account for the ability of MHC products to bind so many different cell surface antigens we propose that interactions in general among macromolecules on the surface of a membrane may be dramatically enhanced by a purely physical effect. This effect derives from the confinement of membrane macromolecules to an effective volume which is the product of membrane surface area times d, the distance over which the center of mass of the molecules can move in a vertical direction (perpendicular to the membrane surface). Because d is very small the effective concentrations of surface molecules are extremely high and their interactions are correspondingly enhanced.  相似文献   
40.
Type I allergy, an immunodisorder that affects almost 20% of the population worldwide, is based on the immunoglobulin E (IgE) recognition of per se innocuous antigens (allergens). Pollen from wind-pollinated plants belong to the most potent allergen sources. We report the isolation of a cDNA coding for a 8.6 kDa two EF-hand calcium binding allergen, Phl p 7, from a timothy grass (Phleum pratense) pollen expression cDNA library, using serum IgE from a grass pollen allergic patient. Sequence analysis identified Phl p 7 as a member of a recently discovered subfamily of pollen-specific calcium binding proteins. Recombinant Phl p 7 was expressed in Escherichia coli and purified to homogeneity as determined by mass spectroscopy. Approximately 10% of pollen allergic patients displayed IgE reactivity to rPhl p 7 and Phl p 7-homologous allergens present in pollens of monocotyledonic and dicotyledonic plants. Circular dichroism analysis of the calcium-bound and apo-rPhl p 7 indicated that differences in IgE recognition may be due to calcium-induced changes in the protein conformation. The fact that patients mount IgE antibodies against different protein conformations is interpreted as a footprint of a preferential sensitization against either form. The biological activity of rPhl p 7 was demonstrated by its ability to induce basophil histamine release and immediate type skin reactions in sensitized individuals. In conclusion, IgE binding to Phl p 7 represents an example for the conformation-dependent IgE recognition of an allergen. Recombinant Phl p 7 may be used for diagnosis and perhaps treatment of a group of patients who suffer from allergy to pollens of many unrelated plant species.  相似文献   
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