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1.
Suzanne Camus Sergio Menéndez Kenneth Fernandes Nelly Kua Geng Liu Dimitris P. Xirodimas David P. Lane Jean-Christophe Bourdon 《Cell cycle (Georgetown, Tex.)》2012,11(8):1646-1655
The discovery that the single p53 gene encodes several different p53 protein isoforms has initiated a flurry of research into the function and regulation of these novel p53 proteins. Full-length p53 protein level is primarily regulated by the E3-ligase Mdm2, which promotes p53 ubiquitination and degradation. Here, we report that all of the novel p53 isoforms are ubiquitinated and degraded to varying degrees in an Mdm2-dependent and -independent manner, and that high-risk human papillomavirus can degrade some but not all of the novel isoforms, demonstrating that full-length p53 and the p53 isoforms are differentially regulated. In addition, we provide the first evidence that Mdm2 promotes the NEDDylation of p53β. Altogether, our data indicates that Mdm2 can distinguish between the p53 isoforms and modify them differently. 相似文献
2.
Energy storage in arthropods has important implications for survival and reproduction. The lipid content of 276 species of adult arthropods with wet mass in the range 0.2–6.13 g is determined to assess how lipid mass scales with body mass. The relative contribution of lipids to total body mass is investigated with respect to phylogeny, ontogeny and sex. The lipid content of adult insects, arachnids, and arthropods in general shows an isometric scaling relationship with respect to body mass (M) (Marthropod lipid = ?1.09 ×Mdry1.01 and Marthropod lipid = ?1.00 ×Mlean0.98). However, lipid allocation varies between arthropod taxa, as well as with sex and developmental stage within arthropod taxa. Female insects and arachnids generally have higher lipid contents than males, and larval holometabolous insects and juvenile arachnids have higher lipid contents than adults. 相似文献
3.
Rechargeable graphite dual‐ion batteries (GDIBs) have attracted the attention of electrochemists and material scientists in recent years due to their low cost and high‐performance metrics, such as high power density (≈3–175 kW kg?1), energy efficiency (≈80–90%), long cycling life, and high energy density (up to 200 Wh kg?1), suited for grid‐level stationary storage of electricity. The key feature of GDIBs is the exploitation of the reversible oxidation of the graphite network with concomitant and highly efficient intercalation/deintercalation of bulky anionic species between graphene layers. In this review, historical and current research aspects of GDIBs are discussed, along with key challenges in their development and practical deployment. Specific emphasis is given to the operational mechanism of GDIBs and to unbiased and correct reporting of theoretical cell‐level energy densities. 相似文献
4.
Victor F. Medina Peter M. Jeffers Steven L. Larson Waleska Perez 《International journal of phytoremediation》2000,2(4):287-295
Bleach treatment of plants was studied as a simple alternative to axenic tissue cultures for demonstrating phytodegradation of aqueous and gas-phase environmental contaminants. Parrotfeather (Myriophyllum aquaticum), spinach (Spinacia oleracea), and wheat (Triticum aestivum) were exposed to 0.525% NaC10 solutions for 15 s, then rinsed in deionized water. Plate counts indicated that 97 to 100% of viable bacteria were removed from parrotfeather and spinach. Transformation rates for 2,4,6-trinitrotoluene (TNT) by bleached and untreated parrotfeather were virtually identical. Similarly, treated and untreated spinach, wheat heads, and wheat leaves removed methyl bromide (MeBr) from air at the same rates. However, wheat root with attendant adhering soil was rendered inactive by bleach treatment. Parrotfeather roots examined by dissecting microscope and by electron microscope showed no significant damage caused by bleach treatment. 相似文献
5.
6.
In the present study, non‐thermal dielectric barrier discharge (DBD) plasma of induced structural changes of morin resulted in the isolation of one previously undescribed benzofuranone derivative, along with two known compounds. The chemical structures of these degradation products were elucidated by UV, NMR and FAB‐MS spectroscopic analyses. The isolated three compounds showed potent antioxidative activities in two different tests, with IC50 values in the range of 12.9–41.8 μm in the 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS+) radical scavenging activity, 19.0–71.9 μm for hydroxyl radical scavenging activity test. Furthermore, the new methoxylated benzofuranone exhibited enhancement of inhibitory effects against pancreatic lipase with an IC50 value of 90.7±1.6 μm , when compared to the parent morin. These results suggested that the degradation products isolated from plasma exposed morin might be beneficial for prevention of obesity and related diseases. 相似文献
7.
Sara Ceballos Florentina Álvarez-Marqués 《Journal of experimental marine biology and ecology》2006,339(2):189-203
The reproductive activity and the physiological state of the calanoid copepods Calanus helgolandicus and Calanoides carinatus were investigated off the coast of NW Spain during autumn to evaluate the effect of short food resources on both populations. Phytoplankton biomass was low, and neither phytoplankton size distribution nor composition was suitable to support high reproductive rates. Accordingly, egg production rates (EPR) were much lower than maximum rates for both species, pointing to food limitation. The reproductive index (RI), which represents the proportion of females with mature gonads, was < 50% at each of the three zones into which the sampling area was divided (coast, shelf and ocean). Potential recruitment rates were very low except at some nearshore stations, where the highest concentrations of chlorophyll-a (Chl-a), diatoms, dinoflagellates and large cells were found. EPR of C. helgolandicus and C. carinatus were correlated with phytoplankton biomass and unaffected by temperature. Phytoplankton carbon ingestion explained ca. 50% of the variability in EPR for both species. At most of the stations, herbivory was insufficient to cover the carbon requirements for reproduction and respiration, so females probably fed on heterotrophic prey to meet their demands. However, given the low fecundity observed, this omnivorous diet did not seem to be optimum for reproduction, and a severe food limitation is thus suggested. Furthermore, the high C/N values measured point to a notable lipid storage, but given the low EPR found, lipid reserves were probably invested into female maintenance rather than into gonad maturation. C. helgolandicus and C. carinatus populations did not mirror phytoplankton biomass distribution, but they correlated well when considering only copepodites V (CV). The CV could be preparing for the overwintering, storing lipid reserves to ensure a successful diapause, and they could also be advected by the poleward current detected during the study. Females showed a diel feeding rhythm, with highest ingestion rates during night. From our results, it follows that C. helgolandicus and C. carinatus females did not perform diel vertical migrations. We suggest that this behaviour is likely due to the food-limiting conditions, which make it more advantageous to remain at the surface during daytime. 相似文献
8.
9.
J. P. Barkham 《Biodiversity and Conservation》1995,4(8):857-868
Despite the growth in awareness and practical action to maintain biodiversity, environmental degradation and ecosystem destruction has continued at a high rate over the last 20 years. The roots of this lie in the predominant international economic order, underpinned by lifestyle demands for increased material consumption. Net flow of wealth from South (less developed) to North (more developed) nations has exacerbated a spiral of increased poverty and environmental degradation in the former. Global environmental conservation depends upon a radical change of direction with the principle of equity as the starting point. Notwithstanding the importance of continuing to add to local and small-scale conservation achievements, the prospect of radical change happening seems small, despite it being in the long-term self-interest of the North. The concept of equity is, apparently, unacceptable to Northern electorates. 相似文献
10.
Few fish species form single, panmictic populations throughout their geographic range, most form subpopulations or 'stocks' with differing levels of interconnectivity. Different patterns of interconnectivity between subpopulations will give rise to different responses to exploitation and management, but they will also have different capacities to generate the genetic and phenotypic differences often used to discriminate between stocks. Consequently, knowledge of ontogenetic and seasonal patterns in the distribution, movement and behaviour of individuals is crucial to identifying population substructure. This paper considers the evidence gathered about movements and behaviour of adult fishes from mark-recapture and electronic tagging studies for a number of fish species in the North Sea and elsewhere in U.K. waters in an attempt to understand population structure and the processes that may give rise to it. 相似文献