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1.
Grooming in primates is often considered a “currency” that can be exchanged for other “services” or “commodities” such as reciprocal grooming, coalitionary support, infant handling, tolerance around food sources, active food sharing, or mating opportunities. Previous studies on primate grooming‐for‐sex exchange viewed the males as the demanding class, with the females as suppliers of mating opportunities. In this study, we examine the broader context of grooming‐for‐mating exchange in Barbary macaques in Gibraltar. Our data show that Barbary macaque males groom females with whom they are mating more frequently and for longer periods than other females, and the relationship between grooming and mating remains significant in both sexual and nonsexual contexts. In addition, females groomed males with whom they were mating more frequently and for longer periods than other males. In both sexes, grooming was observed to be far more frequent and to occur for longer durations in sexual compared to nonsexual contexts. We did not find any difference in grooming behavior between presexual and postsexual contexts. Our data suggest that there is no simple model to describe Barbary macaque grooming patterns in sexual contexts. Although our results are partly consistent with male use of grooming as payment for mating, broadly assessed grooming‐mating patterns cannot be solely explained by a male‐driven grooming‐for‐mating exchange.  相似文献   
2.
Summary A system was developed which allows the transfer of foreign genes into apricot cultivars. We report the transformation and regeneration of Prunus armeniaca plants with Agrobacterium tumefaciens strain LBA 4404 containing various binary plasmids, pBinGUSint, carrying the marker gene ß-glucuronidase (GUS) and pBinPPVm, carrying the coat protein gene of Plum Pox Virus (PPV). The marker gene GUS was used for optical evaluation of the efficiency of the transformation system. The coat protein gene of PPV was used to introduce coat protein mediated resistance against one of the most important pathogens of stone fruit trees in Europe and the whole Mediterranean area. This is the first report of the successful integration of a viral coat protein gene into a fruit tree species, opening a new perspective on the control of the disease.Abbreviations GUS ß-glucuronidase - PPV Plum Pox Virus - BA 6-benzylaminopurine - NPTII neomycin phosphotransferase II - CP coat protein - CaMV Cauliflower Mosaic Virus - P35S 35S promoter - MS Murashige and Skoog - PCR polymerase chain reaction - P/C/I phenol/chloroform/isoamylalcohol - RNase ribonuclease - dNTP deoxyribonucleosidetriphosphate - DMSO dimethyl sulfoxide  相似文献   
3.
A seven-amino-acid cleavage site specific for tobacco etch virus (TEV) protease was introduced into SecA at two separate positions after amino acids 195 and 252. Chromosomal wild-type secA was replaced by these secA constructs. Simultaneous expression of TEV protease led to cleavage of both SecA derivatives. In the functional SecA dimer, proteolysis directly indicated surface exposure of the TEV protease cleavage sites. Cleavage of SecA near residue 195 generated an unstable proteolysis product and a secretion defect, suggesting that this approach could be used to inactivate essential proteins in vivo.  相似文献   
4.
Escherichia coli can synthesize trehalose in response to osmotic stress and is able to utilize trehalose as a carbon source. The pathway of trehalose utilization is different at low and high osmolarity. At high osmolarity, a periplasmic trehalase (TreA) is induced that hydrolyzes trehalose in the periplasm to glucose. Glucose is then taken up by the phosphotransferase system. At low osmolarity, trehalose is taken up by a trehalose-specific enzyme II of the phosphotransferase system as trehalose-6-phosphate and then is hydrolyzed to glucose and glucose-6-phosphate. Here we report a novel cytoplasmic trehalase that hydrolyzes trehalose to glucose. treF, the gene encoding this enzyme, was cloned under ara promoter control. The enzyme (TreF) was purified from extracts of an overexpressing strain and characterized biochemically. It is specific for trehalose exhibiting a Km of 1.9 mM and a Vmax of 54 micromol of trehalose hydrolyzed per min per mg of protein. The enzyme is monomeric, exhibits a broad pH optimum at 6.0, and shows no metal dependency. TreF has a molecular weight of 63,703 (549 amino acids) and is highly homologous to TreA. The nonidentical amino acids of TreF are more polar and more acidic than those of TreA. The expression of treF as studied by the expression of a chromosomal treF-lacZ fusion is weakly induced by high osmolarity of the medium and is partially dependent on RpoS, the stationary-phase sigma factor. Mutants producing 17-fold more TreF than does the wild type were isolated.  相似文献   
5.
In Poland, distribution of non-native pumpkinseed Lepomis gibbosus (Centrarchidae) is strictly limited to the Oder river basin, where it was introduced in the early 20th century. Recently, several populations have been found in waterbodies adjacent to the Oder, particularly in its lower reaches. In this study, we compare the genetic relatedness of populations in the Oder basin with other European populations using nuclear (microsatellite) and mitochondrial (partial cytochrome c oxidase subunit I; cox1) markers. Microsatellite analysis indicated that four populations in the lower Oder form a separate cluster, while one in the middle Oder clustered with Danubian populations, from where probably having been introduced. Microsatellite data suggested that the lower Oder populations differ from other non-native European populations, making it impossible to estimate the source of introduction. Nevertheless, analysis of cox1 indicated that Oder pumpkinseeds belong to the same haplotype as the vast majority of European populations. Parasitological examination confirmed the presence of two North American species, the monogenean Onchocleidus dispar and trematode Posthodiplostomum centrarchi, in the lower Oder, both previously unknown in the region. Fifteen other parasite species were acquired, including glochidia of invasive Sinanodonta woodiana. In the middle Oder, parasite infection was more limited. Fish from the Gryfino Canal, considered one of the most invasive populations in Europe, showed the highest parasite abundance and diversity, and the highest somatic condition and growth rate due to warm water released from the Dolna Odra power plant. Our results highlight significant differences in somatic condition and parasite infection in long-established non-native pumpkinseed populations in the same river system, reflecting mainly environmental conditions.  相似文献   
6.
In these studies, the Bordetella pertussis adenylate cyclase toxin-hemolysin homology to the Escherichia coli hemolysin is extended with the finding of cyaC, a homolog to the E. coli hlyC gene, which is required for the production of a functional hemolysin molecule in E. coli. Mutations produced in the chromosome of B. pertussis upstream from the structural gene for the adenylate cyclase toxin revealed a region which was necessary for toxin and hemolytic activities of the molecule. These mutants produced the 216-kDa adenylate cyclase toxin as determined by Western blot (immunoblot) analysis. The adenylate cyclase enzymatic activities of these mutants were equivalent to that of wild type, but toxin activities were less than 1% of that of wild type, and the mutants were nonhemolytic on blood agar plates and in in vitro assays. The upstream region restored hemolytic activity when returned in trans to the mutant strains. This genetic complementation defined a gene which acts in trans to activate the adenylate cyclase toxin posttranslationally. Sequence analysis of the upstream region defined an open reading frame with homology to the E. coli hlyC gene. In contrast to E. coli, this open reading frame is oriented oppositely from the adenylate cyclase toxin structural gene.  相似文献   
7.
An age-specific life table for the chicken miteDermanyssus gallinae (DeGeer, 1778) was based on various observations carried out at 25°C. The generation time was calculated to be 16.8 days; the intrinsic rate of natural increase was 0.12 per day, and the net reproductive rate was 7.2. A nonlinear function was found satisfactory to describe the developmental rate of the different immature lifestages at temperatures below 40°C. The stage-specific survival of the immature life-stages was generally high between 10 and 37°C, but decreased quickly outside this temperature range. Most of the eggs were laid during the first three weeks of the adult life. The proportion of surviving females rapidly decreases after moulting to the adult stage. At a temperature of 30°C, the highest number of eggs (3 eggs per day) was laid.  相似文献   
8.
Abscisic acid (ABA) was applied in a concentration of 1. 10?3 M and 1. 10?4 M to the quantitative SD plantChenopodium rubrum under various light regimes. ABA did not influence flowering in plants under continuous illumination, enhanced flowering in plants subjected to long days and inhibited it in plants induced by short days. It was concluded that ABA can not substitute for inductive treatment but its action may be additive to initial stages of reproductive morphogenesis (enhanced growth rate and branching of the apical meristem) as evoked by long days.  相似文献   
9.
InEchinops the flowers are surrounded by several scales and initiated in an acropetal and spiral succession on a cone-like inflorescence axis (Figs. 1–6). The floral organs originate in the following sequence: petals—stamens—carpels—pappus. The petals arise from a meristematic rim and therefore are already interconnected when they arise as primordia. This sympetalous zone remains rather inconspicuous for a long period, but eventually, the elongated corolla tube is formed through intercalary growth in a ring zone. Thereby, the stamens are moved upwards and form ledges on the corolla tube (Fig. 34). In the inferior ovary the usual zones of the typical angiospermous gynoecium can be distinguished, namely a synascidiate, symplicate and hemisymplicate zone. The ovule is borne on carpellary tissue.
  相似文献   
10.
WW domain binding protein 1‐like (WBP1L), also known as outcome predictor of acute leukaemia 1 (OPAL1), is a transmembrane adaptor protein, expression of which correlates with ETV6‐RUNX1 (t(12;21)(p13;q22)) translocation and favourable prognosis in childhood leukaemia. It has a broad expression pattern in haematopoietic and in non‐haematopoietic cells. However, its physiological function has been unknown. Here, we show that WBP1L negatively regulates signalling through a critical chemokine receptor CXCR4 in multiple leucocyte subsets and cell lines. We also show that WBP1L interacts with NEDD4‐family ubiquitin ligases and regulates CXCR4 ubiquitination and expression. Moreover, analysis of Wbp1l‐deficient mice revealed alterations in B cell development and enhanced efficiency of bone marrow cell transplantation. Collectively, our data show that WBP1L is a novel regulator of CXCR4 signalling and haematopoiesis.  相似文献   
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