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Bentho-Pelagic Divergence Of Cichlid Feeding Architecture Has Been Consistent And Prodigious During Multiple Adaptive Radiations Within African Rift-Lakes, R. Craig Albertson, W. J. Cooper, K. J. Parsons, A. M. McIntyre, B. S. Kern, A. C. McGee-Moore 2010 University of Massachusetts - Amherst

Bentho-Pelagic Divergence Of Cichlid Feeding Architecture Has Been Consistent And Prodigious During Multiple Adaptive Radiations Within African Rift-Lakes, R. Craig Albertson, W. J. Cooper, K. J. Parsons, A. M. Mcintyre, B. S. Kern, A. C. Mcgee-Moore

R. Craig Albertson

How particular changes in functional morphology can repeatedly promote ecological diversification is an active area of evolutionary investigation. The African rift-lake cichlids offer a calibrated time series of the most dramatic adaptive radiations of vertebrate trophic morphology yet described, and the replicate nature of these events provides a unique opportunity to test whether common changes in functional morphology have repeatedly facilitated their ecological success.


Molecular Pedomorphism Underlies Craniofacial Skeletal Evolution In Antarctic Notothenioid Fishes, R. Craig Albertson, Y-L Yan, T. A. Titus, E. Pisano, M. Vacchi, P. C. Yelick, W. H. Detrich, J. H. Postlethwait 2010 University of Massachusetts - Amherst

Molecular Pedomorphism Underlies Craniofacial Skeletal Evolution In Antarctic Notothenioid Fishes, R. Craig Albertson, Y-L Yan, T. A. Titus, E. Pisano, M. Vacchi, P. C. Yelick, W. H. Detrich, J. H. Postlethwait

R. Craig Albertson

Background

Pedomorphism is the retention of ancestrally juvenile traits by adults in a descendant taxon. Despite its importance for evolutionary change, there are few examples of a molecular basis for this phenomenon. Notothenioids represent one of the best described species flocks among marine fishes, but their diversity is currently threatened by the rapidly changing Antarctic climate. Notothenioid evolutionary history is characterized by parallel radiations from a benthic ancestor to pelagic predators, which was accompanied by the appearance of several pedomorphic traits, including the reduction of skeletal mineralization that resulted in increased buoyancy. Results

We compared craniofacial skeletal development in two ...


Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, GM Burkart, RC Augustine, E Kerdavid, E Tuzel, M Bezanilla 2010 University of Massachusetts - Amherst

Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, Gm Burkart, Rc Augustine, E Kerdavid, E Tuzel, M Bezanilla

Magdalena Bezanilla

Class XI myosins are plant specific and responsible for cytoplasmic streaming. Because of the large number of myosin XI genes in angiosperms, it has been difficult to determine their precise role, particularly with respect to tip growth. The moss Physcomitrella patens provides an ideal system to study myosin XI function. P. patens has only two myosin XI genes, and these genes encode proteins that are 94% identical to each other. To determine their role in tip growth, we used RNA interference to specifically silence each myosin XI gene using 5′ untranslated region sequences. We discovered that the two myosin XI ...


Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner 2010 University of Massachusetts - Amherst

Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner

Patricia Wadsworth

TPX2 is a Ran-regulated spindle assembly factor that is required for kinetochore fiber formation and activation of the mitotic kinase Aurora A. TPX2 is enriched near spindle poles and is required near kinetochores, suggesting that it undergoes dynamic relocalization throughout mitosis. Using photoactivation, we measured the movement of PA-GFP-TPX2 in the mitotic spindle. TPX2 moves poleward in the half-spindle and is static in the interzone and near spindle poles. Poleward transport of TPX2 is sensitive to inhibition of dynein or Eg5 and to suppression of microtubule flux with nocodazole or antibodies to Kif2a. Poleward transport requires the C terminus of ...


Multiple Domains In The Crumbs Homolog 2a (Crb2a) Protein Are Required For Regulating Rod Photoreceptor Size, Abigail Jensen, Y. C. Hsu 2010 University of Massachusetts - Amherst

Multiple Domains In The Crumbs Homolog 2a (Crb2a) Protein Are Required For Regulating Rod Photoreceptor Size, Abigail Jensen, Y. C. Hsu

Abigail Jensen

Background Vertebrate retinal photoreceptors are morphologically complex cells that have two apical regions, the inner segment and the outer segment. The outer segment is a modified cilium and is continuously regenerated throughout life. The molecular and cellular mechanisms that underlie vertebrate photoreceptor morphogenesis and the maintenance of the outer segment are largely unknown. The Crumbs (Crb) complex is a key regulator of apical membrane identity and size in epithelia and in Drosophila photoreceptors. Mutations in the human gene CRUMBS HOMOLOG 1 (CRB1) are associated with early and severe vision loss. Drosophila Crumbs and vertebrate Crb1 and Crumbs homolog 2 (Crb2 ...


Fast Microtubule Dynamics In Meiotic Spindles Measured By Single Molecule Imaging: Evidence That The Spindle Environment Does Not Stabilize Microtubules, Thomas J. Maresca, D. J. Needleman, A. Groen, R. Ohi, L. Mirny, T. Mitchison 2010 University of Massachusetts - Amherst

Fast Microtubule Dynamics In Meiotic Spindles Measured By Single Molecule Imaging: Evidence That The Spindle Environment Does Not Stabilize Microtubules, Thomas J. Maresca, D. J. Needleman, A. Groen, R. Ohi, L. Mirny, T. Mitchison

Thomas J. Maresca

Metaphase spindles are steady-state ensembles of microtubules that turn over rapidly and slide poleward in some systems. Since the discovery of dynamic instability in the mid-1980s, models for spindle morphogenesis have proposed that microtubules are stabilized by the spindle environment. We used single molecule imaging to measure tubulin turnover in spindles, and nonspindle assemblies, in Xenopus laevis egg extracts. We observed many events where tubulin molecules spend only a few seconds in polymer and thus are difficult to reconcile with standard models of polymerization dynamics. Our data can be quantitatively explained by a simple, phenomenological model—with only one adjustable ...


Thyroid Hormone May Regulate Mrna Abundance In Liver By Acting On Micrornas, H. Doug, M. Paquette, A. Williams, R. Thomas Zoeller, M. Wade, C. Yauk 2010 University of Massachusetts - Amherst

Thyroid Hormone May Regulate Mrna Abundance In Liver By Acting On Micrornas, H. Doug, M. Paquette, A. Williams, R. Thomas Zoeller, M. Wade, C. Yauk

R. Thomas Zoeller

MicroRNAs (miRNAs) are extensively involved in diverse biological processes. However, very little is known about the role of miRNAs in mediating the action of thyroid hormones (TH). Appropriate TH levels are known to be critically important for development, differentiation and maintenance of metabolic balance in mammals. We induced transient hypothyroidism in juvenile mice by short-term exposure to methimazole and perchlorate from post natal day (PND) 12 to 15. The expression of miRNAs in the liver was analyzed using Taqman Low Density Arrays (containing up to 600 rodent miRNAs). We found the expression of 40 miRNAs was significantly altered in the ...


Evolution Of A Unique Predatory Feeding Apparatus: Functional Anatomy, Development And A Genetic Locus For Jaw Laterality In Lake Tanganyika Scale-Eating Cichlids, R. Craig Albertson, T. A. Stewart 2010 University of Massachusetts - Amherst

Evolution Of A Unique Predatory Feeding Apparatus: Functional Anatomy, Development And A Genetic Locus For Jaw Laterality In Lake Tanganyika Scale-Eating Cichlids, R. Craig Albertson, T. A. Stewart

R. Craig Albertson

Background While bilaterality is a defining characteristic of triploblastic animals, several assemblages have managed to break this symmetry in order to exploit the adaptive peaks garnered through the lateralization of behaviour or morphology. One striking example of an evolved asymmetry in vertebrates comes from a group of scale-eating cichlid fishes from Lake Tanganyika. Members of the Perissodini tribe of cichlid fishes have evolved dental and craniofacial asymmetries in order to more effectively remove scales from the left or right flanks of prey. Here we examine the evolution and development of craniofacial morphology and laterality among Lake Tanganyika scale-eating cichlids. Results ...


Body Mass Index, Adiposity Rebound And Early Feeding In A Longitudinal Cohort (Raine Study), Paola Chivers, Beth P. Hands, Helen Parker, Max K. Bulsara, Lawrence Beilin, Garth Kendall, Wendy Oddy 2010 University of Notre Dame Australia

Body Mass Index, Adiposity Rebound And Early Feeding In A Longitudinal Cohort (Raine Study), Paola Chivers, Beth P. Hands, Helen Parker, Max K. Bulsara, Lawrence Beilin, Garth Kendall, Wendy Oddy

Health Sciences Papers and Journal Articles

Objective: This study examined the influence of type and duration of infant feeding on adiposity rebound and the tracking of body mass index (BMI) from birth to 14 years.

Methods: A sample of 1330 individuals over eight follows-ups was drawn from the Western Australian Pregnancy Cohort (Raine) Study. Trajectories of BMI from birth to adolescence using linear mixed model (LMM) analysis investigated the influence of age breastfeeding stopped and age other milk introduced (binomial 4-month cut-point). A sub-sample of LMM predicted BMI was used to determine BMI and age at nadir for early infant feeding groups.

Results: Chi square analysis ...


New Species In The Genus Monoecocesuts (Cestoda: Anoplocephalidae) From Neotropical Rodents (Caviidae And Sigmodontidae), Terry Haverkost, Scott Lyell Gardner 2010 University of Nebraska - Lincoln

New Species In The Genus Monoecocesuts (Cestoda: Anoplocephalidae) From Neotropical Rodents (Caviidae And Sigmodontidae), Terry Haverkost, Scott Lyell Gardner

Scott Gardner Publications & Papers

Anoplocephalid cestodes have a worldwide distribution, but relatively few species are known from South American rodents. By examining the collections of the Harold W. Manter Laboratory of Parasitology and the United States National Parasite Collection, 6 new species of Monoecocestus Beddard, 1914, are described, along with a redescription of Monoecocestus mackiewiczi Schmidt and Martin, 1978, based on the type specimens. The discussion includes commentary about uterine development, an important taxonomic character of the family, the vaginal dilation in immature segments (a character of potential taxonomic importance), and the implication of host usage to the evolutionary history and biogeography of species ...


Field Applications Of Entomopathogenic Fungi Beauveria Bassiana And Metarhizium Anisopliae F52 (Hypocreales: Clavicipitaceae) For The Control Of Ixodes Scapularis (Acari: Ixodidae), Kirby C. Stafford III, Sandra A. Allan 2010 Connecticut Agricultural Experiment Station

Field Applications Of Entomopathogenic Fungi Beauveria Bassiana And Metarhizium Anisopliae F52 (Hypocreales: Clavicipitaceae) For The Control Of Ixodes Scapularis (Acari: Ixodidae), Kirby C. Stafford Iii, Sandra A. Allan

Publications from USDA-ARS / UNL Faculty

Two commercial formulations of Beauveria bassiana (Balsamo-Crivelli) Vuillemin were applied to residential sites in Old Lyme, CT, for the control of nymphs of the blacklegged tick, Ixodes scapularis, in 1999 and 2000. The pyrethroid bifenthrin was applied to other premises for comparison with B. bassiana. A wood chip barrier was installed and maintained at six of the treated properties. In 1999, control of I. scapularis nymphs ranged from 74.5 to 83.0% on lawns without wood chips and from 88.9 to 90% on lawns with wood chip barriers. As a control check, no ticks (n= 23) collected at ...


Nih Guidelines On Human Embryonic Stem Cell Research In Context: Clarity Or Confusion?, Karen H. Rothenberg, Michael R. Ulrich 2010 University of Maryland School of Law

Nih Guidelines On Human Embryonic Stem Cell Research In Context: Clarity Or Confusion?, Karen H. Rothenberg, Michael R. Ulrich

Faculty Scholarship

No abstract provided.


Permanent Genetic Resources Added To The Molecular Ecology Resources Database 1 February 2010–31 March 2010, D. Aurelle, M. R. Pooler, T. A. Rinehart, B. E. Scheffler, MOLECULAR ECOLOGY RESOURCES PRIMER DEVELOPMENT CONSORTIUM 2010 Aix-Marseille Université

Permanent Genetic Resources Added To The Molecular Ecology Resources Database 1 February 2010–31 March 2010, D. Aurelle, M. R. Pooler, T. A. Rinehart, B. E. Scheffler, Molecular Ecology Resources Primer Development Consortium

Publications from USDA-ARS / UNL Faculty

This article documents the addition of 228 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anser cygnoides, Apodemus flavicollis, Athene noctua, Cercis canadensis, Glis glis, Gubernatrix cristata, Haliotis tuberculata, Helianthus maximiliani, Laricobius nigrinus, Laricobius rubidus, Neoheligmonella granjoni, Nephrops norvegicus, Oenanthe javanica, Paramuricea clavata, Pyrrhura orcesi and Samanea saman. These loci were cross-tested on the following species: Apodemus sylvaticus, Laricobius laticollis and Laricobius osakensis (a proposed new species currently being described).


Thermal And Mechanical Properties Of Compression-Molded Pmdi-Reinforced Pcl/Gluten Composites, Abdellatif Mohamed, Victoria L. Finkenstadt, Sherald H. Gordon, Debra E. Palmquist 2010 USDA-ARS

Thermal And Mechanical Properties Of Compression-Molded Pmdi-Reinforced Pcl/Gluten Composites, Abdellatif Mohamed, Victoria L. Finkenstadt, Sherald H. Gordon, Debra E. Palmquist

Publications from USDA-ARS / UNL Faculty

Many biopolymers and synthetic polymers composites were developed by different researchers for environmental protection and for cost reduction. One of these composites is polycaprolactone (PCL) and vital wheat gluten or wheat flour composites were prepared and compatibilized with polymeric diphenylmethane diisocyanate (pMDI) by blending and compression-molding. PCL/pMDI blend exhibited glass transition (Tg) at -67 °C (0.20 J/g/ °C) and vital gluten at 63 °C (0.45 J/g/ °C), whereas no Tg was recorded for wheat flour. Although Tg was unmistakable for either PCL or gluten, all composite exhibited one Tg, which is ...


The Prospects For Sequencing The Western Corn Rootworm Genome, Nicholas Miller, S. Richards, T. W. Sappington 2010 University of Nebraska-Lincoln

The Prospects For Sequencing The Western Corn Rootworm Genome, Nicholas Miller, S. Richards, T. W. Sappington

Faculty Publications: Department of Entomology

Historically, obtaining the complete sequence of eukaryotic genomes has been an expensive and complex task. For this reason, efforts to sequence insect genomes have largely been confined to model organisms, species that are important to human health and representative species from a few insect orders. This situation is set to change as a number of ‘next generation’ sequencing technologies are making largescale DNA sequencing both affordable and accessible. Sequencing the genome of the western corn rootworm, Diabrotica virgifera virgifera, is likely to become a realistic proposition within the next 2 years. In the meantime, there is an active community of ...


Modeling Evolution Of Diabrotica Virgifera Virgifera (Coleoptera: Chrysomelidae) To Transgenic Corn With Two Insecticidal Traits, David W. Onstad, Lance J. Meinke 2010 University of Illinois, Urbana

Modeling Evolution Of Diabrotica Virgifera Virgifera (Coleoptera: Chrysomelidae) To Transgenic Corn With Two Insecticidal Traits, David W. Onstad, Lance J. Meinke

Faculty Publications: Department of Entomology

Asimulation model of the population dynamics and genetics of western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), was created to evaluate the use of refuges in the management of resistance to transgenic insecticidal corn, Zea mays L., expressing one or two toxin traits. Hypothetical scenarios and a case study of a corn hybrid pyramided with existing toxins are simulated. In the hypothetical situations, results demonstrated that evolution is generally delayed by pyramids compared with deployment of a single-toxin corn hybrid. However, soil insecticide use in the refuge reduced this delay and quickened the evolution of resistance. Results were sensitive ...


Degree-Day Requirements For Alfalfa Weevil (Coleoptera: Curculionidae) Development In Eastern Nebraska, A. R. Stilwell, Robert J. Wright, Thomas E. Hunt, Erin E. Blankenship 2010 University of Nebraska-Lincoln

Degree-Day Requirements For Alfalfa Weevil (Coleoptera: Curculionidae) Development In Eastern Nebraska, A. R. Stilwell, Robert J. Wright, Thomas E. Hunt, Erin E. Blankenship

Faculty Publications: Department of Entomology

The alfalfa weevil, Hypera postica (Gyllenhal), is a serious, yet sporadic defoliator of alfalfa, Medicago sativa L., in Nebraska. A 2-yr study was conducted in 2005 and 2006 to test for variation in degree-day requirements by location in eastern Nebraska. Sampling took place along a latitudinal gradient in three regions of eastern Nebraska. Three fields were sampled in each region during the 2 yr of the study. Alfalfa weevil larval degree-day requirements were found to vary by latitude in eastern Nebraska. Alfalfa weevil larvae were discovered in southern regions after fewer developmental degree-days had accumulated than in fields in the ...


Varroa Mites And Honey Bee Health: Can Varroa Explain Part Of The Colony Losses?, Yves Le Conte, Marion D. Ellis, Wolfgang Ritter 2010 Laboratoire de Biologie et Protection de l’abeille

Varroa Mites And Honey Bee Health: Can Varroa Explain Part Of The Colony Losses?, Yves Le Conte, Marion D. Ellis, Wolfgang Ritter

Faculty Publications: Department of Entomology

Since 2006, disastrous colony losses have been reported in Europe and North America. The causes of the losses were not readily apparent and have been attributed to overwintering mortalities and to a new phenomenon called Colony Collapse Disorder. Most scientists agree that there is no single explanation for the extensive colony losses but that interactions between different stresses are involved. As the presence of Varroa in each colony places an important pressure on bee health, we here address the question of how Varroa contributes to the recent surge in honey bee colony losses.


Biotic And Abiotic Influences On Within-Plant Distribution Of Soybean Aphid (Hemiptera: Aphididae: Aphis Glycines), Tierney R. Brosius, Leon G. Higley, Thomas E. Hunt 2010 University of Nebraska-Lincoln

Biotic And Abiotic Influences On Within-Plant Distribution Of Soybean Aphid (Hemiptera: Aphididae: Aphis Glycines), Tierney R. Brosius, Leon G. Higley, Thomas E. Hunt

Faculty Publications: Department of Entomology

The within-plant distribution of soybean aphid, Aphis glycines Matsumura has been attributed to various causes, yet it is unclear which factor or combination of factors most influence aphid within-plant distribution. Understanding soybean aphid distribution within the soybean canopy is important both in developing sampling programs and in evaluating injury. Because natural enemies have the potential to alter aphid dispersion, we examined how within-plant distribution of soybean aphid was influenced by different natural enemies. Field cages of different mesh diameters were used to exclude different sizes of natural enemies from aphid infested plots. Plots were surveyed and both natural enemy density ...


Rna Interference As A Method For Target-Site Screening In The Western Corn Rootworm, Diabrotica Virgifera Virgifera, Analiza P. Alves, Marce D. Lorenzen, Richard W. Beeman, John E. Foster, Blair D. Siegfried 2010 University of Nebraska-Lincoln

Rna Interference As A Method For Target-Site Screening In The Western Corn Rootworm, Diabrotica Virgifera Virgifera, Analiza P. Alves, Marce D. Lorenzen, Richard W. Beeman, John E. Foster, Blair D. Siegfried

Faculty Publications: Department of Entomology

To test the efficacy of RNA interference (RNAi) as a method for target-site screening in Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) larvae, genes were identified and tested for which clear RNAi phenotypes had been identified in the Coleopteran model, Tribolium castaneum. Here the cloning of the D. v. vergifera orthologs of laccase 2 (DvvLac2) and chitin synthase 2 (DvvCHS2) is reported. Injection of DvvLac2-specific doublestranded RNA resulted in prevention of post-molt cuticular tanning, while injection of DvvCHS2- specific dsRNA reduced chitin levels in midguts. Silencing of both DvvLac2 and DvvCHS2 was confirmed by RT-PCR and quantitative RT-PCR. As in T ...


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