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101.
Sequence analysis of cohesive ends of the actinophage RP3 genome and construction of a transducible shuttle vector 总被引:2,自引:0,他引:2
Abstract The sequence of the cohesive ends of actinophage RP3 DNA has been determined. As with all other phages of Gram-positive bacteria that have been studied sofar, RP3 DNA has 3'-protruding ends. A shuttle cosmid has been constructed containing this cos area which can be efficiently transduced by phage RP3 to host cells of Streptomyces rimosus . 相似文献
102.
103.
Krützen M Sherwin WB Connor RC Barré LM Van de Casteele T Mann J Brooks R 《Proceedings. Biological sciences / The Royal Society》2003,270(1514):497-502
Male bottlenose dolphins (Tursiops sp.) in Shark Bay have one of the most complex male societies outside humans. Two broad mating strategies have been identified in males. In the first strategy, there are two types of alliances: stable 'first-order' pairs and trios that herd individual females in reproductive condition, and 'second-order' teams of two first-order alliances (five or six individuals) that join forces against rivals in contests for females. In the alternative strategy, a 'super-alliance' of ca. 14 individuals, males form pairs or trios to herd females, but in contrast to the stable alliances, these pairs and trios are highly labile. Here, we show that males in stable first-order alliances and the derived second-order alliances are often strongly related, so that they may gain inclusive fitness benefits from alliance membership. By contrast, members of the super-alliance are no more closely related than expected by chance. Further, the strength of the association of alliance partners within the super-alliance, as measured by an index of joint participation in consorting a female, was not correlated with their genetic relatedness. Thus, within one population and one sex, it appears that there may be simultaneous operation of more than one mode of group formation. 相似文献
104.
For the first time a complete ostracode and trilobite fauna is described from the Dobrovitá Formation (Ordovician) of Perunica. In contrast to the trilobite fauna the ostracode fauna evidences close relations to both Armorica and Baltica. The trilobite fauna comprises 11 species out of 11 genera, the ostracode fauna comprises 15 (5 new) species out of 15 (1 new) genera. 相似文献
105.
Hauke Thomsen Miguel Inacio da Silva Filho Michael Fuchs Sabine Ponader Elke Pogge von Strandmann Lewin Eisele Stefan Herms Per Hoffmann Andreas Engert Kari Hemminki Asta F?rsti 《PloS one》2016,11(4)
Genome-wide association studies (GWASs) have identified several, mainly co-dominantly acting, single-nucleotide polymorphisms (SNPs) associated with Hodgkin lymphoma (HL). We searched for recessively acting disease loci by performing an analysis of runs of homozygosity (ROH) based on windows of homozygous SNP-blocks and by calculating genomic inbreeding coefficients on a SNP-wise basis. We used data from a previous GWAS with 906 cases and 1217 controls from a population with a long history of no matings between relatives. Ten recurrent ROHs were identified among 25 055 ROHs across all individuals but their association with HL was not genome-wide significant. All recurrent ROHs showed significant evidence for natural selection. As a novel finding genomic inbreeding among cases was significantly higher than among controls (P = 2.11*10−14) even after correcting for covariates. Higher inbreeding among the cases was mainly based on a group of individuals with a higher average length of ROHs per person. This result suggests a correlation of higher levels of inbreeding with higher cancer incidence and might reflect the existence of recessive alleles causing HL. Genomic inbreeding may result in a higher expression of deleterious recessive genes within a population. 相似文献
106.
Markus Hoffmann Nadine Krüger Pawel Zmora Florian Wrensch Georg Herrler Stefan P?hlmann 《PloS one》2016,11(3)
New World bats have recently been discovered to harbor influenza A virus (FLUAV)-related viruses, termed bat-associated influenza A-like viruses (batFLUAV). The internal proteins of batFLUAV are functional in mammalian cells. In contrast, no biological functionality could be demonstrated for the surface proteins, hemagglutinin (HA)-like (HAL) and neuraminidase (NA)-like (NAL), and these proteins need to be replaced by their human counterparts to allow spread of batFLUAV in human cells. Here, we employed rhabdoviral vectors to study the role of HAL and NAL in viral entry. Vectors pseudotyped with batFLUAV-HAL and -NAL were able to enter bat cells but not cells from other mammalian species. Host cell entry was mediated by HAL and was dependent on prior proteolytic activation of HAL and endosomal low pH. In contrast, sialic acids were dispensable for HAL-driven entry. Finally, the type II transmembrane serine protease TMPRSS2 was able to activate HAL for cell entry indicating that batFLUAV can utilize human proteases for HAL activation. Collectively, these results identify viral and cellular factors governing host cell entry driven by batFLUAV surface proteins. They suggest that the absence of a functional receptor precludes entry of batFLUAV into human cells while other prerequisites for entry, HAL activation and protonation, are met in target cells of human origin. 相似文献
107.
108.
Hypereutrophication of U.S. surface waters is one of the leading causes of impairment for water quality. With nutrient criteria development and total maximum daily load (TMDL) issues looming for regulators, agricultural research is focusing on practices aimed at decreasing nutrient contributions to receiving aquatic ecosystems. This study examined the use of rice (Oryza sativa) for luxury uptake of nitrogen and phosphorus components associated with agricultural storm runoff. Mesocosms (379 L) planted with rice were exposed to two concentrations (5 and 10 mg/L) of nitrate, ammonia, and orthophosphorus. Results from these mesocosms were compared to unvegetated controls (also amended with 5 or 10 mg/L nitrate, ammonia, and orthophosphorus) to determine efficiency of rice in remediating nutrient runoff. Statistically significant differences in ammonia and nitrate retention of vegetated mesocosms amended with 5 mg/L versus vegetated mesocosms amended with 10 mg/L were noted after the first exposure. Although rice is a nutrient-dependent aquatic plant, this study suggests that more efficient mitigation is possible at lower inflow concentrations as opposed to higher inflow concentrations. 相似文献
109.
Isabelle E. J. A. Fran?ois Anna Bink Jo Vandercappellen Kathryn R. Ayscough Alexandre Toulmay Roger Schneiter Elke van Gyseghem Guy Van den Mooter Marcel Borgers Davy Vandenbosch Tom Coenye Bruno P. A. Cammue Karin Thevissen 《The Journal of biological chemistry》2009,284(47):32680-32685
Azoles inhibit ergosterol biosynthesis, resulting in ergosterol depletion and accumulation of toxic 14α-methylated sterols in membranes of susceptible yeast. We demonstrated previously that miconazole induces actin cytoskeleton stabilization in Saccharomyces cerevisiae prior to induction of reactive oxygen species, pointing to an ancillary mode of action. Using a genome-wide agar-based screening, we demonstrate in this study that S. cerevisiae mutants affected in sphingolipid and ergosterol biosynthesis, namely ipt1, sur1, skn1, and erg3 deletion mutants, are miconazole-resistant, suggesting an involvement of membrane rafts in its mode of action. This is supported by the antagonizing effect of membrane raft-disturbing compounds on miconazole antifungal activity as well as on miconazole-induced actin cytoskeleton stabilization and reactive oxygen species accumulation. These antagonizing effects point to a primary role for membrane rafts in miconazole antifungal activity. We further show that this primary role of membrane rafts in miconazole action consists of mediating intracellular accumulation of miconazole in yeast cells. 相似文献
110.