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Full-Text Articles in Life Sciences
Conservation In The Context Of Climate Change: Practical Guidelines For Land Protection At Local Scales, Kevin Ruddock, Peter August, Christopher Damon, Charles Labash, Pamela Rubinoff, Donald Robadue Jr.
Conservation In The Context Of Climate Change: Practical Guidelines For Land Protection At Local Scales, Kevin Ruddock, Peter August, Christopher Damon, Charles Labash, Pamela Rubinoff, Donald Robadue Jr.
Peter August
Climate change will affect the composition of plant and animal communities in many habitats and geographic settings. This presents a dilemma for conservation programs – will the portfolio of protected lands we now have achieve a goal of conserving biodiversity in the future when the ecological communities occurring within them change? Climate change will significantly alter many plant communities, but the geophysical underpinnings of these landscapes, such as landform, elevation, soil, and geological properties, will largely remain the same. Studies show that extant landscapes with a diversity of geophysical characteristics support diverse plant and animal communities. Therefore, geophysically diverse landscapes …
Encyclopedia Of Animal Behavior, A. Payne, P. Starks, Aviva Liebert
Encyclopedia Of Animal Behavior, A. Payne, P. Starks, Aviva Liebert
Aviva E Liebert
The Encyclopedia of Animal Behavior has engaged-with great success-the efforts of many of the best behavioral biologists of the 21st century. Section editors drawn from the most accomplished behavioral scientists of their generation have enrolled an international cast of highly respected thinkers and writers-all of whom have taken great care and joy in illuminating every imaginable corner of animal behavior. This comprehensive work covers not only the usual topics such as communication, learning, sexual selection, navigation, and the history of the field, but also emerging topics in cognition, animal welfare, conservation, and applications of animal behavior. The large section on …
Taming Of The Skew: Transactional Models Fail To Predict Reproductive Partitioning In The Paper Wasp Polistes Dominulus, Aviva Liebert, Philip Starks
Taming Of The Skew: Transactional Models Fail To Predict Reproductive Partitioning In The Paper Wasp Polistes Dominulus, Aviva Liebert, Philip Starks
Aviva E Liebert
Female Polistes paper wasps can initiate colonies either solitarily or in cooperative groups. Reproduction is often distributed unequally in groups, even to the point of complete monopolization of breeding by the dominant group member. Transactional models of reproductive skew predict the degree of reproductive partitioning, assuming that the dominant controls group membership and will yield a proportion of reproduction to a subordinate as an incentive to stay peacefully in the group. Using a combination of demographic, genetic and morphological data from a population of P. dominulus, we test predictions of 'classical' two-person skew models as well as more complex …
The Relationships Between Cuticular Hydrocarbon Composition, Faunal Assemblages, Inter-Island Distance, And Population Genetic Variation In Tuscan Archipelago Wasps, Leonardo Dapporto, Aviva Liebert, Philip Starks, Stefano Turillazzi
The Relationships Between Cuticular Hydrocarbon Composition, Faunal Assemblages, Inter-Island Distance, And Population Genetic Variation In Tuscan Archipelago Wasps, Leonardo Dapporto, Aviva Liebert, Philip Starks, Stefano Turillazzi
Aviva E Liebert
Until recently, studies examining the geographical distribution of insects in the Tuscan Archipelago have focused on paleogeography as the primary influence on species distributions. However, for flying insects such as Hymenoptera that may be able to disperse over water, current geographical location is likely to be more important in determining present distributions within the Archipelago. Here we compare mainland and island wasp populations using genetic variation and cuticular hydrocarbon composition of the vespid wasp Polistes dominulus, and species composition of wasps in the family Pompilidae. Both chemical and genetic data result in similar clustering of P. dominulus populations that reflect …
Sexual Interactions And Nestmate Recognition In Invasive Populations Of Polistes Dominulus Wasps, Aviva Liebert, N Wilson-Rich, C Johnson, Philip Starks
Sexual Interactions And Nestmate Recognition In Invasive Populations Of Polistes Dominulus Wasps, Aviva Liebert, N Wilson-Rich, C Johnson, Philip Starks
Aviva E Liebert
Many social insect species have mating systems or recognition abilities that minimize the chance of inbreeding. In haplodiploid systems, inbreeding is especially costly due to the production of sterile offspring such as diploid males. Diploid males (and their triploid offspring) have been identified in invasive populations of the paper wasp, Polistes dominulus, but to date have not been reported in its native populations. Due to the degree of genetic diversity in the invasive populations, it is unlikely that the production of these genetic ‘misfits’ is the result of a genetic bottleneck alone, but rather that errors in nestmate recognition may …
Nest Hydrocarbons As Cues For Philopatry In A Paper Wasp, Annagiri Sumana, Aviva Liebert, Anne Berry, Ghislaine Switz, Colin Orians, Philip Starks
Nest Hydrocarbons As Cues For Philopatry In A Paper Wasp, Annagiri Sumana, Aviva Liebert, Anne Berry, Ghislaine Switz, Colin Orians, Philip Starks
Aviva E Liebert
Philopatric behavior has been demonstrated in a wide taxonomic spread of animals. In temperate environments, overwintered Polistes wasp foundresses often return to their natal nest prior to initiating colony construction. Previous research has shown that these spring foundresses can identify the natal nest in the absence of landmark and gross morphological cues. Hydrocarbons are essential recognition cues for Polistes nest and nestmate discrimination, but cuticular hydrocarbon profiles can become homogenized when foundresses overwinter in mixed colony groups. We examined the hydrocarbon profiles of Polistes dominulus foundresses and nests before and after an overwintering period, and found that the hydrocarbon profiles …
Extreme Polygyny: Multi-Seasonal “Hypergynous” Nesting In The Introduced Paper Wasp Polistes Dominulus, Aviva Liebert, Julia Hui, Peter Nonacs, Philip Starks
Extreme Polygyny: Multi-Seasonal “Hypergynous” Nesting In The Introduced Paper Wasp Polistes Dominulus, Aviva Liebert, Julia Hui, Peter Nonacs, Philip Starks
Aviva E Liebert
In temperate climates, female paper wasps typically initiate new colonies in the spring. Several nest-founding tactics have been documented in Polistes species, including solitary nest initiation, joining a cooperative association, usurping an existing nest, or adopting an abandoned nest. Occasionally, exceptionally large groups of females have also been found reusing nests from the previous season. Here we report this phenomenon in introduced populations of the Eurasian species Polistes dominulus. We describe in detail the demographic and genetic characteristics of one such spring colony from Los Angeles, California, USA, which was collected with 84 associated adults and all stages of developing …
Solitary Nesting And Reproductive Success In The Paper Wasp Polistes Aurifer, Aviva Liebert, Peter Nonacs, Robert Wayne
Solitary Nesting And Reproductive Success In The Paper Wasp Polistes Aurifer, Aviva Liebert, Peter Nonacs, Robert Wayne
Aviva E Liebert
Female Polistes paper wasps are capable of independent nesting, yet many populations demonstrate a mixture of solitary and cooperative nest foundation. Previous studies of Polistes have found survival and/or productivity advantages of cooperative nest foundation compared to solitary nesting, and reproductive skew models have been designed to predict the dynamics of such flexible cooperation. In this paper, we examine the success of different nesting strategies in a previously unstudied population of Polistes aurifer in southern California. The colony cycle of this population is less synchronous than that of other temperate species, and the frequency of solitary nesting averages 86.2%. Our …
Wolbachia In The Invasive European Paper Wasp Polistes Dominulus, J Stahlhut, Aviva Liebert, Philip Starks, Leonardo Dapporto, J Jaenike
Wolbachia In The Invasive European Paper Wasp Polistes Dominulus, J Stahlhut, Aviva Liebert, Philip Starks, Leonardo Dapporto, J Jaenike
Aviva E Liebert
The European paper wasp Polistes dominulus has been expanding its North American range since its introduction in the 1970s. We screened P. dominulus from Italy and the northeastern U.S. for the presence of the intracellular reproductive symbiont Wolbachia. Infection rates among females varied from 16% to 87% among U.S. sites and from 33% to 71% in Italy. We also found infected haploid and diploid males, indicating that this is not a male-killing Wolbachia infection. Our data show that infected individuals from New York, Massachusetts, and Italy carry the same Wolbachia strain, and that some mtDNA haplotypes include both infected and …
Diploid Males And Their Triploid Offspring In The Paper Wasp Polistes Dominulus, Aviva Liebert, Annagiri Sumana, Philip Starks
Diploid Males And Their Triploid Offspring In The Paper Wasp Polistes Dominulus, Aviva Liebert, Annagiri Sumana, Philip Starks
Aviva E Liebert
Although the hymenopteran sex-determining mechanism generally results in haploid males and diploid females, diploid males can be produced via homozygosity at the sex-determining locus. Diploid males have low fitness because they are effectively sterile or produce presumably sterile triploid offspring. Previously, triploid females were observed in three species of North American Polistes paper wasps, and this was interpreted as indirect evidence of diploid males. Here we report what is, to our knowledge, the first direct evidence: four of five early male-producing Polistes dominulus nests from three populations contained diploid males. Because haploid males were also found, however, the adaptive value …
Strand Exchange Protein 1 (Sep1) From Saccharomyces Cerevisiae Does Not Promote Branch Migration In Vitro, Zhaoqing Zhang, Amanda Simons, Vidya Prabhu, Junghuei Chen
Strand Exchange Protein 1 (Sep1) From Saccharomyces Cerevisiae Does Not Promote Branch Migration In Vitro, Zhaoqing Zhang, Amanda Simons, Vidya Prabhu, Junghuei Chen
Amanda Simons
It has been shown in vitro that Saccharomyces cerevisiae strand exchange protein 1 (Sep1) promotes the transfer of one strand of a linear duplex DNA to a homologous single-stranded DNA circle. Sep1 also has an exonuclease active on DNA and RNA. By using exonuclease III-treated linear duplex DNA with various lengths of single-stranded tail as well as Ca2+ to inhibit the exonuclease activity of Sep1, we show that the processivity of exonuclease activity of Sep1 is greater than previously reported. The results in this work also demonstrate that the joint molecule between the linear duplex and single-stranded circle observed from …
Brca1 Dna-Binding Activity Is Stimulated By Bard1, Amanda Simons, Andrew Horwitz, Lea Starita, Karen Griffin, R Williams, J.N. Glover, Jeffrey Parvin
Brca1 Dna-Binding Activity Is Stimulated By Bard1, Amanda Simons, Andrew Horwitz, Lea Starita, Karen Griffin, R Williams, J.N. Glover, Jeffrey Parvin
Amanda Simons
The breast- and ovarian-specific tumor suppressor BRCA1 has been implicated in numerous cellular processes, including transcription, ubiquitination, and DNA repair. Its tumor suppression activity is tightly linked to that of BARD1, a protein that heterodimerizes with BRCA1. It has been previously shown that BRCA1 binds to DNA, an interesting functional observation in light of the genetic data linking BRCA1 to DNA repair pathways. In this work, we reexamine the DNA-binding properties of BRCA1, comparing them with the DNA-binding properties of the BRCA1/BARD1 heterodimer. Because nuclear BRCA1 exists as a heterodimer with BARD1, it is likely that in vitro studies of …
Direct Dna Binding Activity Of The Fanconi Anemia D2 Protein, Woo-Hyun Park, Steven Margossian, Andrew Horwitz, Amanda Simons, Alan D'Andrea, Jeffrey Parvin
Direct Dna Binding Activity Of The Fanconi Anemia D2 Protein, Woo-Hyun Park, Steven Margossian, Andrew Horwitz, Amanda Simons, Alan D'Andrea, Jeffrey Parvin
Amanda Simons
It is known that the Fanconi anemia D2 protein is vital for protecting the genome from DNA damage, but what activities this protein has are unknown. In these experiments we purified full-length Fanconi anemia protein D2 (FANCD2), and we found that FANCD2 bound to DNA with specificity for certain structures: double strand DNA ends and Holliday junctions. Proteins containing patient-derived mutations or artificial variants of the FANCD2 protein were similarly expressed and purified, and each variant bound to the Holliday junction DNA with similar affinity as did the wild-type protein. There was no single discrete domain of FANCD2 protein that …
Ground Nesting In The Paper Wasp Polistes Aurifer (Hymenoptera: Vespidae), Aviva Liebert
Ground Nesting In The Paper Wasp Polistes Aurifer (Hymenoptera: Vespidae), Aviva Liebert
Aviva E Liebert
Polistes paper wasp species vary in their nest site selection, with some nesting in relatively exposed areas and others in protected cavities. Locating the nest sites of cavity dwelling species in natural habitat can prove difficult, and most behavioral studies on these species are therefore conducted using human-built structures. Since Hungerford and Williams (1912) and Rau (1929) noted the location of several P. fuscatus (Fabricius) nests in rodent burrows, there have been no published accounts of ground nesting Polistes species. I report the occurrence of a large, dense cluster of P. aurifer (Saussure) nests located within cracks in the dried …
P53 Blocks Ruvab Promoted Branch Migration And Modulates Resolution Of Holliday Junctions By Ruvc1, Vidya Prabhu, Amanda Simons, Hiroshi Iwasaki, Dahai Gai, Daniel Simmons, Junghuei Chen
P53 Blocks Ruvab Promoted Branch Migration And Modulates Resolution Of Holliday Junctions By Ruvc1, Vidya Prabhu, Amanda Simons, Hiroshi Iwasaki, Dahai Gai, Daniel Simmons, Junghuei Chen
Amanda Simons
The Holliday junction is the central intermediate in homologous recombination. Branch migration of this four-stranded DNA structure is a key step in genetic recombination that affects the extent of genetic information exchanged between two parental DNA molecules. Here, we have constructed synthetic Holliday junctions to test the effects of p53 on both spontaneous and RuvAB promoted branch migration as well as the effect on resolution of the junction by RuvC. We demonstrate that p53 blocks branch migration, and that cleavage of the Holliday junction by RuvC is modulated by p53. These findings suggest that p53 can block branch migration promoted …
Recombinant Expression Of Indolicidin Concatemers In Escherichia Coli, K Morin, S Arcidiacono, Richard Beckwitt, C Mello
Recombinant Expression Of Indolicidin Concatemers In Escherichia Coli, K Morin, S Arcidiacono, Richard Beckwitt, C Mello
Richard D Beckwitt
Antimicrobial peptides are part of the innate immune system of vertebrates and invertebrates. They are active against gram-negative and gram-positive bacteria, fungi, and protozoa. Currently, most antimicrobial peptides are extracted from host organisms or produced by solidphase peptide synthesis. Recombinant protein expression in Escherichia coli is a tool for greater production yields at a decreased cost and reduces the use of hazardous materials. We have constructed a concatamer of indolicidin and successfully expressed a fusion product with thioredoxin in E. coli BL21DE3. Codons for methionine residues flanking individual indolicidin genes were incorporated for cyanogen bromide cleavage of the fusion protein …
Phylogeny And Historical Biogeography Of The Spider Genus Lutica (Araneae, Zodariidae), Richard Beckwitt, Richard Beckwitt
Phylogeny And Historical Biogeography Of The Spider Genus Lutica (Araneae, Zodariidae), Richard Beckwitt, Richard Beckwitt
Richard D Beckwitt
Spiders of the genus Lutica from 19 populations in southern California and Baja California, including all the California Channel Islands except Anacapa, were compared electrophoretically on the basis of variability at 15 gene loci. Fixed allelic differences clearly define two species: new species A [Santa Barbara and Ventura Counties, northern Channel Islands (San Miguel, Santa Rosa, Santa Cruz), southern Channel Islands (San Nicolas, Santa Barbara, Santa Catalina)] and new species C [Guerrero Negro, central Baja California], while morphological features define two others: new species B [Los Angeles, Orange and San Diego Counties, northern Baja California] and clementea [San Clemente Island]. …
Developmental Increase In 3h-Muscimol Binding To The Γ-Aminobutyric Acida Receptor In Hypothalamic And Limbic Areas Of The Rat: Why Is The Ventromedial Nucleus Of The Hypothalamus An Exception?, Aline Davis, Margaret Mccarthy
Developmental Increase In 3h-Muscimol Binding To The Γ-Aminobutyric Acida Receptor In Hypothalamic And Limbic Areas Of The Rat: Why Is The Ventromedial Nucleus Of The Hypothalamus An Exception?, Aline Davis, Margaret Mccarthy
Aline Davis
Using in vitro autoradiography to measure binding of the γ-aminobutyric acidA (GABAA) receptor agonist, muscimol, we examined male and female rats on postnatal days 1, 5, 10, and 20. There were no sex differences in muscimol binding in any hypothalamic or limbic regions examined. However, all regions exhibited a developmental increase in the density of binding, except the ventromedial nucleus (VMN) of the hypothalamus. We have previously shown that the adult VMN is the only hypothalamic nucleus containing an abundance of the α2 subunit of the GABAA receptor and lack of the α1 subunit. We hypothesize that the lack of …
Loss Of Steroidogenic Factor 1 Alters Cellular Topography In The Mouse Ventromedial Nucleus Of The Hypothalamus, Aline Davis, Marianne Seney, Nancy Stallings, Liping Zhao, Keith Parker, Stuart Tobet
Loss Of Steroidogenic Factor 1 Alters Cellular Topography In The Mouse Ventromedial Nucleus Of The Hypothalamus, Aline Davis, Marianne Seney, Nancy Stallings, Liping Zhao, Keith Parker, Stuart Tobet
Aline Davis
Knockout (KO) mice lacking the orphan nuclear receptor steroidogenic factor 1 (SF-1) exhibit marked structural abnormalities of the ventromedial nucleus of the hypothalamus (VMH). In this study, we sought to determine the molecular mechanisms underlying the VMH abnormalities. To trace SF-1-expressing neurons, we used a SF-1/enhanced green fluorescent protein (eGFP) transgene. Although the total numbers of eGFP-positive cells in wild-type (WT) and SF-1 KO mice were indistinguishable, cells that normally localize precisely within the VMH were scattered more diffusely in adjacent regions in SF-1 KO mice. This abnormal distribution is likely due to the loss of SF-1 expression in VMH …
Emerging Technologies For Non-Invasive Quantification Of Physiological Oxygen Transport In Plants, P. Chaturvedi, M. Taguchi, S. L. Burrs, B. A. Hauser, W.W. A.W. Salim, Jonathan C. Claussen, E. S. Mclamore
Emerging Technologies For Non-Invasive Quantification Of Physiological Oxygen Transport In Plants, P. Chaturvedi, M. Taguchi, S. L. Burrs, B. A. Hauser, W.W. A.W. Salim, Jonathan C. Claussen, E. S. Mclamore
Jonathan C. Claussen
Oxygen plays a critical role in plant metabolism, stress response/signaling, and adaptation to environmental changes (Lambers and Colmer, Plant Soil 274:7-15, 2005; Pitzschke et al., Antioxid Redox Signal 8:1757-1764, 2006; Van Breusegem et al., Plant Sci 161:405-414, 2001). Reactive oxygen species (ROS), by-products of various metabolic pathways in which oxygen is a key molecule, are produced during adaptation responses to environmental stress. While much is known about plant adaptation to stress (e.g., detoxifying enzymes, antioxidant production), the link between ROS metabolism, O2 transport, and stress response mechanisms is unknown. Thus, non-invasive technologies for measuring O2 are critical for understanding the …