Digital Commons Network^™

Responses Of Nesting Bobolinks (Dolichonyx Oryzivorus) To Habitat Edges, Eric Bollinger, Thomas Gavin

Faculty Research & Creative Activity

T.-Avoidance of habitat edges may be contributing to reduced densities of grass- land birds in small habitat patches. Nest densities for grassland-nesting Bobolinks (Dolichonyx oryzivorus) were much lower than expected within 25 m of forest edges at three sites in New York, and that pattern ("edge avoidance") extended to 100 m at one site. Nests located within 50 m of forest or wooded hedgerow edges had lower daily survival rates, compared with nests >100 m from any habitat edge. Bobolinks tended to move away from forest edges when renest- ing after nest failure; that pattern was especially evident in females …

Immunoglobulin Heavy-Chain Receptor Editing Is Observed In The Nod/Scid Model Of Human B-Cell Development, G. R. Kolar, J. D. Capra

Biological Sciences Faculty Research & Creative Works

Receptor editing and receptor revision are the two mechanisms of antibody diversity that result in either complete V-gene replacement or the formation of hybrid V genes. We do not yet understand how this process unfolds, because they are rare and difficult to study in vivo. In this study, we describe a family of VH4-34:VH4-61 hybrids isolated from a human B-cell chimeric non-obese diabetic/severe combined immunodeficient mouse. The observation of hybrid immunoglobulin sequences in human B cells that developed in this model system makes it useful for the study of this mechanism of diversification and tolerance.

Immunoglobulin Heavy-Chain Receptor Editing Is Observed In The Nod/Scid Model Of Human B-Cell Development, G. R. Kolar, J. D. Capra

Biological Sciences Faculty Research & Creative Works

Receptor editing and receptor revision are the two mechanisms of antibody diversity that result in either complete V-gene replacement or the formation of hybrid V genes. We do not yet understand how this process unfolds, because they are rare and difficult to study in vivo. In this study, we describe a family of VH4-34:VH4-61 hybrids isolated from a human B-cell chimeric non-obese diabetic/severe combined immunodeficient mouse. The observation of hybrid immunoglobulin sequences in human B cells that developed in this model system makes it useful for the study of this mechanism of diversification and tolerance.

Responses Of Nesting Bobolinks (Dolichonyx Oryzivorus) To Habitat Edges, Eric K. Bollinger, Thomas A. Gavin

Faculty Research & Creative Activity

ABSTRACT.-Avoidance of habitat edges may be contributing to reduced densities of grassland birds in small habitat patches. Nest densities for grassland-nesting Bobolinks (Dolichonyx oryzivorus) were much lower than expected within 25m of forest edges at three sites in New York, and that pattern ("edge avoidance") extended to 100m at one site. Nests located within 50 m of forest or wooded hedgerow edges had lower daily survival rates, compared with nests >100m from any habitat edge. Bobolinks tended to move away from forest edges when renesting after nest failure; that pattern was especially evident in females that placed their first nest …

Genetic Analysis Of Song Dialect Populations In Puget Sound White-Crowned Sparrows, Jill Soha, Douglas Nelson, Patricia Parker

Biology Department Faculty Works

The relationship between cultural variation and biological variation among natural populations has been the subject of both theoretical and empirical study. Zonotrichia leucophrys pugetensis is one of three subspecies of white-crowned sparrow known to form geographical song dialects. We investigated whether these dialects correspond to genetic differences among Z. l. pugetensis populations. We compared allele frequencies at four microsatellite loci in males from 11 sites spanning six dialects over the subspecies' range in Oregon and Washington. Cluster analysis and genotype assignment tests indicated no tendency for sample sites within dialect areas to be genetically more similar than are sites from …

Responses Of Kit Foxes (Vulpes Macrotis) To Antipredator Blood-Squirting And Blood Of Texas Horned Lizards (Phrynosoma Cornutum), Wade Sherbrooke, George Middendorf, M Douglas

Department of Biology Faculty Publications

Six related studies were conducted with four captive juvenile Kit Foxes (Vulpes macrotis) to test the hypothesis that blood-squirting from eye-socket tissues by Texas Horned Lizards (Phrynosoma cornutum) is a canid antipredator defense. In 16 trials, naive “hungry” foxes killed and ate adult Yarrow's Spiny Lizards (Sceloporus jarrovii; eight of eight trials) slightly more frequently than adult P. cornutum (six of eight trials). Adverse responses by foxes (head shaking) were seen in five of six trials in which Phrynosoma squirted blood. Later these experienced foxes, fed ad libitum, killed and ate mice (eight of eight trials) while largely ignoring P. …

Constraints On Adaptive Evolution: The Functional Trade-Off Between Reproduction And Fast-Start Swimming Performance In The Trinidadian Guppy (Poecilia Reticulata), Cameron K. Ghalambor, David N. Reznick, Jeffrey A. Walker Phd

Faculty Publications

The empirical study of natural selection reveals that adaptations often involve trade-offs between competing functions. Because natural selection acts on whole organisms rather than isolated traits, adaptive evolution may be constrained by the interaction between traits that are functionally integrated. Yet, few attempts have been made to characterize how and when such constraints are manifested or whether they limit the adaptive divergence of populations. Here we examine the consequences of adaptive life-history evolution on locomotor performance in the live-bearing guppy. In response to increased predation from piscivorous fish, Trinidadian guppies evolve an increased allocation of resources toward reproduction. These populations …

A Patch Hath Smaller Patches: Delineating Ecological Neighborhoods For Parasites, Derek Zelmer, John R. Seed

Faculty Publications

Use of the host individual as a boundary for parasite populations and communities provides an unambiguous spatial unit that is useful for pattern description, but this framework precludes consideration of the host landscape and within-host population dynamics. Recognizing host individuals as spatially and temporally complex landscapes requires modified concepts of parasite populations and communities. An outline of the currently accepted hierarchies of parasite populations and communities is provided on the basis of ecological neighborhoods that are delineated by discrete habitat patches or functional dynamics (or both), as opposed to host individuals. This parasite-based framework accommodates consideration of both within- and …

Cold Induction Of Earli1, A Putative Arabidopsis Lipid Transfer Protein, Is Light And Calcium Dependent, Jason A. Bubier, Michael Schläppi

Biological Sciences Faculty Research and Publications

As sessile organisms, plants must adapt to their environment. One approach toward understanding this adaptation is to investigate environmental regulation of gene expression. Our focus is on the environmental regulation of EARLI1, which is activated by cold and long-day photoperiods. Cold activation of EARLI1 in short-day photoperiods is slow, requiring several hours at 4ºC to detect an increase in mRNA abundance. EARLI1 is not efficiently cold-activated in etiolated seedlings, suggesting that photomorphogenesis is necessary for its cold activation. Cold activation of EARLI1 is inhibited in the presence of the calcium channel blocker lanthanum chloride or the calcium chelator EGTA. Addition …

High Polymorphism In The K-Casein (Csn3) Gene From Wild And Domestic Caprine Species Revealed By Dna Sequencing, Oliver C. Jann, Eva-Maria Prinzenberg, Gordon Luikart, Ana Caroli, Georg Erhardt

Biological Sciences Faculty Publications

We assessed polymorphisms in exon IV of the k-casein gene (CSN3) in ten different breeds of domestic goat (Capra hircus) from three continents and in three related wild caprine taxa (Capra ibex, Capra sibirica and Capra aegagrus). Thirty-five DNA samples were sequenced within a 558 bp fragment of exon IV. Nine polymorphic sites were identified in domestic goat, including four new polymorphisms. In addition to four previously described polymorphic positions, a total of 13 polymorphisms allowed the identification of 13 DNA variants, corresponding to 10 protein variants. Because of conflicting nomenclature of these variants, we propose …

Identification And Functional Analysis Of The Essential And Regulatory Light Chains Of The Only Type Ii Myosin Myo1p In Saccharomyces Cerevisiae, J. Luo, Elizabeth Ann Vallen, C. Dravis, S. E. Tcheperegine, B. Drees, E. Bi

Biology Faculty Works

Cytokinesis in Saccharomyces cerevisiae involves coordination between actomyosin ring contraction and septum formation and/or targeted membrane deposition. We show that Mlc1p, a light chain for Myo2p (type V myosin) and lqg1p (IQGAP), is the essential light chain for Myo1p, the only type 11 myosin in S. cerevisiae. However, disruption or reduction of Mlc1p-Myo1p interaction by deleting the Mlc1p binding site on Myo1p or by a point mutation in MLC1, mlc1-93, did not cause any obvious defect in cytokinesis. In contrast, a different point mutation, mlc1-11, displayed defects in cytokinesis and in interactions with Myo2p and lqg1p. These data suggest that …

Genetic Control Of Branching In Foxtail Millet, Andrew Doust, Katrien Devos, Michael Gadberry, Mike Gale, Elizabeth Kellogg

Biology Department Faculty Works

Reduction in vegetative branching is commonplace when crops are domesticated from their wild progenitors. We have identified genetic loci responsible for these changes in foxtail millet (Setaria italica), a crop closely related to maize but whose genetics are little known. Quantitative trait locus (QTL) analysis and comparative genomics reveal that basal branching (tillering) and axillary branching are partially controlled by separate loci, and that the orthologue of teosinte branched1, the major gene controlling branching phenotype in maize, has only a minor and variable effect. We identify other candidate genes for control of branching, including a number of hormone biosynthesis pathway …

Kinetic Isotope Effects In Ras-Catalyzed Gtp Hydrolysis: Evidence For A Loose Transition State, Xinlin Du, Gavin E. Black, Paolo Lecchi, Fred P. Abramson, Stephen R. Sprang

Biological Sciences Faculty Publications

A remote labeling method has been developed to determine (18)O kinetic isotope effects (KIEs) in Ras-catalyzed GTP hydrolysis. Substrate mixtures consist of (13)C-depleted GTP and [(18)O,(13)C]GTP that contains (18)O at phosphoryl positions of mechanistic interest and (13)C at all carbon positions of the guanosine moiety. Isotope ratios of the nonvolatile substrates and products are measured by using a chemical reaction interface/isotope ratio mass spectrometer. The isotope effects are 1.0012 (0.0026) in the gamma nonbridge oxygens, 1.0194 (0.0025) in the leaving group oxygens (the beta-gamma oxygen and the two beta nonbridge oxygens), and 1.0105 (0.0016) in the two beta nonbridge oxygens. …

Cancer. A Bull's Eye For Targeted Lung Cancer Therapy, John D. Minna, Adi F. Gazdar, Stephen R. Sprang, Joachim Herz

Biological Sciences Faculty Publications

No abstract provided.

Combining Paternally And Maternally Inherited Mitochondrial Dna For Analysis Of Population Structure In Mussels, Robert A. Krebs

Biological, Geological, and Environmental Faculty Publications

Sequence divergence for a fragment of the 16S rRNA gene was compared to identify the advantages in using mitochondrial genes that descend separately through the female and male lineages to examine population structure. The test compared divergence among four local species of freshwater mussels (Unionidae) and was extended to multiple populations of one species, Pyganodon grandis. For the same gene, the male-inherited sequences diverged at a faster rate, producing longer branch lengths in the phylogenies. Of particular use were sequences extracted from P. grandis populations from the southern region of the Lake Erie watershed (Ohio, USA); five male-inherited haplotypes were …

Moving From Pattern To Process: Coexistence Mechanisms Under Intermediate Disturbance Regimes, Katriona Shea, Stephen H. Roxburgh, Emily Rauschert

Biological, Geological, and Environmental Faculty Publications

Coexistence mechanisms that require environmental variation to operate contribute importantly to the maintenance of biodiversity. One famous hypothesis of diversity maintenance under disturbance is the intermediate disturbance hypothesis (IDH). The IDH proposes patterns of peaked diversity under intermediate disturbance regimes, based on a tension between competitively superior species and species which can rapidly colonize following disturbance. We review the literature, and describe recent research that suggests that more than one underlying mechanism can generate this unimodal diversity pattern in disturbed environments. Several exciting emerging research areas are identified, including interactions between disturbance types, operation of the IDH in multi-trophic systems, …

A Plasmodium Gene Family Encoding Maurer’S Cleft Membrane Proteins: Structural Properties And Expression Profiling, Tobili Y. Sam-Yellowe, Laurence Florens, Jeffrey R. Johnson, Tongmin Wang, Judith A. Drazba, Karine G. Le Roch, Yingyao Zhou, Serge Batalov, Daniel J. Carucci

Biological, Geological, and Environmental Faculty Publications

Upon invasion of the erythrocyte cell, the malaria parasite remodels its environment; in particular, it establishes a complex membrane network, which connects the parasitophorous vacuole to the host plasma membrane and is involved in protein transport and trafficking. We have identified a novel subtelomeric gene family in Plasmodium falciparum that encodes II transmembrane proteins localized to the Maurer's clefts. Using coimmunoprecipitation and shotgun proteomics, we were able to enrich specifically for these proteins and detect distinct peptides, allowing us to conclude that four to 10 products were present at a given time. Nearly all of the Pfmc-2tm genes are transcribed …

Nitric Oxide Is Involved In Growth Regulation And Re-Orientation Of Pollen Tubes, Ana Margarida Prado, D. M. Porterfield, José A. Feijó

Biological Sciences Faculty Research & Creative Works

Nitric oxide (NO) controls diverse functions in many cells and organs of animals. It is also produced in plants and has a variety of effects, but little is known about their underlying mechanisms. in the present study, we have discovered a role for NO in the regulation of pollen tube growth, a fast tip-growing cellular system. Pollen tubes must be precisely oriented inside the anatomically complex female ovary in order to deliver sperm. We hypothesized that NO could play a role in this guidance and tested this hypothesis by challenging the growth of pollen tubes with an external NO point …

Watercolors In The Coastal Zone: What Can We See?, Oscar Schofield, Robert A. Arnone, W. Paul Bissett, Tommy D. Dickey, Curtis O. Davis, Zoe Finkel, Matthew Oliver, Mark A. Moline

Biological Sciences

No abstract provided.

Alfred Russel Wallace: A Capsule Biography, Charles H. Smith

DLPS Faculty Publications

No abstract provided.

The New Age Of Hyperspectral Oceanography, Grace Chang, Kevin Mahoney, Amanda Briggs-Whitmire, David Kohler, Curtis Mobley, Marlon Lewis, Mark A. Moline, Emmanuel Boss, Minsu Kim, William Philpot, Tommy Dickey

Biological Sciences

No abstract provided.

Integrating Research And Teaching Labs With The Module Evolution Approach, Michael S. Reagan

Biology Faculty Publications

No abstract provided.

Heritability Of Nectar Traits: Why Do We Know So Little?, Randall J. Mitchell

Biology Faculty Research

Although floral and extrafloral nectar traits are important for plant reproduction and defense, we know little about their genetic basis. Only a handful of studies have quantified heritable variation for nectar traits, primarily in controlled environments that minimize environmental variation. Most such studies have reported strong genetic influences, with heritabilities often >0.35. However, because nectar traits are often very responsive to environmental variation, even substantial amounts of genetic variation may be swamped out in the,field. Environmental variation deserves to be studied in its own right, including exploration of genotype X environment interaction for nectar traits . Most genetic studies of …

Aaas Lecture Series On Women In Science And Engineering, Maribel Vazquez

Publications and Research

The winning essay for a Travel Award from the American Association for the Advancement in Science Women Lecture Series.

http://ehrweb.aaas.org/womeninscience/essays/vazquez.htm

The Impact Of Species Concept On Biodiversity Studies, Keith A. Crandall, Paul-Michael Agapow, Olaf R. P. Bininda-Emonds, John L. Gittleman, Georgina M. Mace, Jonathon C. Marshall, Andy Purvis

Faculty Publications

Species are defined using a variety of different operational techniques. While discussion of the various methodologies has previously been restricted mostly to taxonomists, the demarcation of species is also crucial for conservation biology. Unfortunately, different methods of diagnosing species can arrive at different entities. Most prominently, it is widely thought that use of a phylogenetic species concept may lead to recognition of a far greater number of much less inclusive units. As a result, studies of the same group of organisms can produce not only different species identities but also different species range and number of individuals. To assess the …

Evolution Of Morphological Integration. I. Functional Units Channel Stress-Induced Variation In Shrew Mandibles, Alexander V. Badyaev, Kerry R. Foresman

Biological Sciences Faculty Publications

Stress-induced deviations from normal development are often assumed to be random, yet their accumulation and expression can be influenced by patterns of morphological integration within an organism. We studied within-individual developmental variation ( fluctuating asymmetry) in the mandible of four shrew species raised under normal and extreme environments. Patterns of among-individual variation and fluctuating asymmetry were strongly concordant in traits that were involved in the attachment of the same muscles (i.e., functionally integrated traits), and fluctuating asymmetry was closely integrated among these traits, implying direct developmental interactions among traits involved in the same function. Stress-induced variation was largely confined to …

Homing Endonucleases Encoded By Germ Line-Limited Genes In Tetrahymena Thermophila Have Apetela2 Dna Binding Domains, Jeffrey D. Wuitschick, Paul R. Lindstrom, Alison E. Meyer, Kathleen M. Karrer

Biological Sciences Faculty Research and Publications

Three insertion elements were previously found in a family of germ line-limited mobile elements, the Tlr elements, in the ciliate Tetrahymena. Each of the insertions contains an open reading frame (ORF). Sequence analysis of the deduced proteins encoded by the elements suggests that they are homing endonucleases. The genes are designated TIE1-1, TIE2-1, and TIE3-1 for Tetrahymena insertion-homing endonuclease. The endonuclease motif occupies the amino terminal half of each TIE protein. The C-terminal regions of the proteins are similar to the APETELA2 DNA binding domain of plant transcription factors. The TIE1 and TIE3 elements belong to families of repeated sequences …

A New Species Of Callulina (Anura: Microhylidae) From The West Usambara Mountains, Tanzania, Rafael O. De Sá, Simon P. Loader, Alan Channing

Biology Faculty Publications

The description of the species Callulina kreffti was based on specimens collected in the East Usambara Mountains of Tanzania. Successive collecting has shown this species to be widely distributed through the Eastern Arc Mountains. Advertisement calls from populations in the type locality of Callulina kreffti were compared with calls from populations in the West Usambara Mountains. Analysis of the calls suggested that these two populations of Callulina represent two separate taxa. Subsequent morphological and molecular investigations indicated that these two populations are distinct. Herein, we describe a new Callulina species on the basis of call, morphology and molecular sequences.

Development Of Web Tools For Nlx Simulation Software, Daniel Chai Siriphongs

Loma Linda University Electronic Theses, Dissertations & Projects

Valuable mathematical equations have developed within biology and other sciences (physics, chemistry, etc.) that model various processes, but the complexity of the equations are not easily understood by students, scientists, and those with limited knowledge of the subject area. Simulation software used to visually explain a model is normally proprietary to the specific model equations and cannot be easily adapted to new models by non-programmers. Simulation software needs to be modular and based upon web technologies so that the software can be run on multiple platforms. The NLX simulation software is a group of Java-based objects that can be combined …

Diploid And Polyploid Cytotype Distribution In Melampodium Cinereum And M. Leucanthum (Asteraceae, Heliantheae), Tod F. Stuessy, Hanna Weiss-Schneeweiss, David J. Keil

Biological Sciences

Previous chromosomal studies within Melampodium (Asteraceae, Heliantheae) of Mexico and Central America have documented chromosome numbers n = 9, 10, 11, 12, 18, 20, 23, 25 ± 1, 27, 30, and 33. Some species also have been shown to exhibit infra-and interpopulational polyploidy. The presence of cytotype mixtures is especially pronounced in the white-rayed complex, which occurs in the southwestern United States and adjacent Mexico. This group includes M. cinereum (n = 10 and 20), M. leucanthum (n = 10 and 20), and M. argophyllum (n = 30). Cytotype distribution has been newly analyzed in 415 plants from 152 populations …