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51.
Allison C. Alberts 《Zoo biology》1994,13(5):479-490
Depending on spatial requirements and the distribution of key resources in the environment, social behavior among lizards varies from defense of exclusive territories to the establishment of dominance hierarchies. In captivity or under conditions where dispersal is not possible, dominance hierarchies often emerge in species that are otherwise territorial. This review explores some of the morphological, behavioral, and hormonal determinants of social status in male lizards and how these may lead to differential reproductive function in dominant and subordinate individuals. Emphasis is placed on the importance of population density, local resource dispersion, and the composition and stability of social groups in promoting hierarchical behavior. Results of these studies have ramifications for several aspects of zoo management, including exhibit design, choice of animals to be housed together, provision of resources in space and time, and orientation of enclosures within captive breeding facilities. © 1994 Wiley-Liss, Inc. 相似文献
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53.
Vladimir Vartanian Jocelyn F. Krey Paroma Chatterjee Allison Curtis Makayla Six Sean P. M. Rice Sherri M. Jones Harini Sampath Charles N. Allen Renee C. Ryals R. Stephen Lloyd Peter G. Barr-Gillespie 《Genes, Brain & Behavior》2023,22(4):e12849
Relationships between novel phenotypic behaviors and specific genetic alterations are often discovered using target-specific, directed mutagenesis or phenotypic selection following chemical mutagenesis. An alternative approach is to exploit deficiencies in DNA repair pathways that maintain genetic integrity in response to spontaneously induced damage. Mice deficient in the DNA glycosylase NEIL1 show elevated spontaneous mutations, which arise from translesion DNA synthesis past oxidatively induced base damage. Several litters of Neil1 knockout mice included animals that were distinguished by their backwards-walking behavior in open-field environments, while maintaining frantic forward movements in their home cage environment. Other phenotypic manifestations included swim test failures, head tilting and circling. Mapping of the mutation that conferred these behaviors showed the introduction of a stop codon at amino acid 4 of the Ush1g gene. Ush1gbw/bw null mice displayed auditory and vestibular defects that are commonly seen with mutations affecting inner-ear hair-cell function, including a complete lack of auditory brainstem responses and vestibular-evoked potentials. As in other Usher syndrome type I mutant mouse lines, hair cell phenotypes included disorganized and split hair bundles, as well as altered distribution of proteins for stereocilia that localize to the tips of row 1 or row 2. Disruption to the bundle and kinocilium displacement suggested that USH1G is essential for forming the hair cell's kinocilial links. Consistent with other Usher type 1 models, Ush1gbw/bw mice had no substantial retinal degeneration compared with Ush1gbw/+ controls. In contrast to previously described Ush1g alleles, this new allele provides the first knockout model for this gene. 相似文献
54.
David B. Allison Stanley Heshka Fbernard S. Gorman Steven B. Heymsfield 《Obesity (Silver Spring, Md.)》1993,1(5):339-344
This investigation tested whether distributions of certain aspects of eating behavior were consistent with the notion of a “mixture model;” that is, two or more distinct Commingled component distributions, consistent with the possibility of major gene action. Undergraduates (n=901) completed self-report trait measures of hunger, disinhibition, and dietary restraint. Variables were residualized for gender and age and transformed to remove skewness. Residualized transformed distributions were tested for departure from unimodality with Hartigan's (14) dip statistic. The distributions of all three aspects of eating behavior were significantly non-unimodal. Next, component multivariate normal distributions were estimated via maximum likelihood. Likelihood ratio tests were employed to compare nested models. A mixture of four distributions with unequal variance-covariance matrices tit significantly better than any more parsimonious model. In sum, these data strongly suggest that the distributions of several measures of eating behavior are composed of four component distributions. This finding is consistent with the possibility of major gene effects for eating behavior. 相似文献
55.
Marie E. Portuallo David Y. Lu Gretchen M. Alicea Joel Bolling Rebecca Lee Jennifer McQuade Allison Betof Warner Michael Davies Ashani Weeraratna Jessie Villanueva Vito W. Rebecca 《Pigment cell & melanoma research》2023,36(5):441-447
The inaugural Diversity and Inclusion in Science Session was held during the 2021 Society for Melanoma Research (SMR) congress. The goal of the session was to discuss diversity, equity, and inclusion in the melanoma research community and strategies to promote the advancement of underrepresented melanoma researchers. An international survey was conducted to assess the diversity, equity, and inclusion (DEI) climate among researchers and clinicians within the Society for Melanoma Research (SMR). The findings suggest there are feelings and experiences of inequity, bias, and harassment within the melanoma community that correlate with one's gender, ethnic/racial group, and/or geographic location. Notably, significant reports of inequity in opportunity, discrimination, and sexual harassment demonstrate there is much work remaining to ensure all scientists in our community experience an academic workplace culture built on mutual respect, fair access, inclusion, and equitable opportunity. 相似文献
56.
Maureen L. Stanton Allison A. Snow Steven N. Handel Judith Bereczky 《Evolution; international journal of organic evolution》1989,43(2):335-346
We conducted field experiments to determine how a naturally occurring petal-color polymorphism influences mating patterns in wild radish (Raphanus raphanistrum). The polymorphism is controlled at a single genetic locus, with white petal color being completely dominant to yellow. In experimental populations with equal numbers of yellow- and white-flowered homozygous individuals, insect visitors strongly discriminated against white flowers. Pieris rapae, the most frequent pollinator, was almost 50% more likely to visit yellow than white flowers. Maternal fecundity did not differ between the morphs and was not significantly influenced by a plant's compatibility with potential donors, suggesting that seed production was not limited by receipt of compatible pollen. In contrast, the yellow-flowered morph sired approximately 75% of all seeds produced during the study. This paternity proportion was consistently greater than that expected on the basis of postpollination compatibility measures and was indistinguishable from that expected on the basis of pollinator-visitation frequency. We conclude that the male-fitness advantage of the yellow morph resulted from enhanced pollen export due to the greater attractiveness of its flowers to insect pollinators. With color morphs evenly distributed in experimental arrays, insects did not move assortatively on the basis of petal color, and we found no evidence for assortative pollen flow due to the floral polymorphism. Once postpollination compatibility relationships within populations were taken into account, paternal success of yellow donors did not differ between yellow- and white-flowered maternal plants. 相似文献
57.
Deborah M. Briercheck Timothy J. Allison John P. Richardson Jeffery F. Ellena Todd C. Wood Gordon S. Rule 《Journal of biomolecular NMR》1996,8(4):429-444
Summary Protein fragments containing the RNA-binding domain of Escherichia coli rho protein have been over-expressed in E. coli. NMR spectra of the fragment containing residues 1–116 of rho protein (Rho116) show that a region of this protein is unfolded in solution. Addition of (dC)10 to this fragment stabilizes the folded form of the protein. The fragment comprising residues 1–130 of rho protein (Rho130) is found to be stably folded, both in the absence and presence of nucleic acid. NMR studies of the complex of Rho 130 with RNA and DNA oligonucleotides indicate that the binding-site size, affinity, and specificity of Rho 130 are similar to those of intact rho protein; therefore, Rho 130 is a suitable model of the RNA-binding domain of rho protein. NMR line widths as well as titration experiments of Rho130 complexed with oligonucleotides of various lengths suggest that Rho130 forms oligomers in the presence of longer oligonucleotides. 1H, 15N and 13C resonance assignments were facilitated by the utilization of two pulse sequences, CN-NOESY and CCH-TOCSY. The secondary structure of unliganded Rho130 has been determined by NMR techniques, and it is clear that the RNA-binding domain of rho is more structurally similar to the cold shock domain than to the RNA recognition motif.Abbreviations Rho116, Rho130
protein containing the first 116 (130) residues of rho
- CSD
cold shock domain
- RRM
RNA recognition motif
- RBD
RNA-binding domain
- IPTG
isopropyl -D-thiogalactopyranoside
- EDTA
ethylenediaminetetraacetic acid
- NOE
nuclear Overhauser enhancement 相似文献
58.
Luminol-enhanced chemiluminescence was measured in fresh whole human blood, or human neutrophils isolated from heparinized blood, human alveolar macrophages and rat alveolar macrophages stimulated with bacterial endotoxin (LPS). Tetraacetate esters of rooperol, a dicatechol showing anticytokine activity, added to cells simultaneously with LPS inhibited the respiratory burst. The effective concentrations of rooperol were in the range of 1-10 muM depending on cell type and corresponded well with inhibition of nitric oxide production by rat alveolar macrophages. Thus rooperol may reduce some effects of excessive phagocytic activity and inflammatory reaction but by quenching free radicals production may also diminish the resistance to bacterial infections. 相似文献
59.
The carboxy-terminal two-thirds of the cowpea chlorotic mottle bromovirus capsid protein is incapable of virion formation yet supports systemic movement. 下载免费PDF全文
Previous investigations into recombination in cowpea chlorotic mottle bromovirus (CCMV) resulted in the recovery of an unusual recombinant virus, 3-57, which caused a symptomless infection of cowpeas but formed no detectable virions. Sequence analysis of cDNA clones derived from 3-57 determined that mutations near the 5' terminus of the capsid protein gene introduced an early translational termination codon. Further mutations introduced a new in-frame start codon that allowed translation of the 3' two-thirds of the capsid protein gene. Based on the mutations observed in 3-57, wild-type CCMV clones were modified to determine if the carboxyl two-thirds of the capsid protein functions independently of the complete protein in long-distance movement. Analysis of these mutants determined that while virion formation is not required for systemic infection, the carboxy-terminal two-thirds of the capsid protein is both required and sufficient for systemic movement of viral RNA. This indicates that the CCMV capsid protein is multifunctional, with a distinct long-distance movement function in addition to its role in virion formation. 相似文献
60.
Characterization of predominant bacteria from the colons of normal and dysenteric pigs. 总被引:9,自引:6,他引:3 下载免费PDF全文
Bacterial populations adherent to the mucosa of the proximal colons of weaned, healthy pigs were compared with populations from pigs with dysentery induced by inoculation with a culture of Treponema hyodysenteriae. Isolates (136) representative of the predominant flora adherent to colonic epithelia of normal pigs and isolates (162) from pigs with dysentery were cultured anaerobically on a rumen fluid-based medium and characterized. Most (71%) of the isolates from colonic epithelia of normal pigs were gram positive, whereas 88% of the epithelia-associated isolates from pigs with dysentery were gram negative. The geometric mean of colony counts was 5.7 X 10(7)/cm2 of colonic tissue from three normal pigs and 7.7 X 10(8)/cm2 from four pigs with dysentery. A number of isolates obtained from contents of the lumens of normal pigs with dysentery were also characterized. Comparison of isolates from epithelial tissue and from contents of the lumens of the same pig indicated that these populations were different. Our results indicate that physiological changes that occur in the colons of pigs with dysentery are accompanied by marked changes in the microbial populations in the colons. The factors which regulate the population changes are not yet understood. 相似文献