Biology Commons^™

The Uptake Of Amino Acids By Microbes And Trees In Three Cold-Temperate Forests, Adrien C. Finzi, Sean T. Berthrong

Scholarship and Professional Work - LAS

Amino acids are emerging as a critical component of the terrestrial N cycle, yet there is little understanding of amino acid cycling in temperate forests. This research studied the uptake and turnover of amino acid N by soil microbes and the capacity of forest trees to take up the amino acid glycine in comparison to NH₄⁺ and NO₃⁻. This research was conducted in three temperate forests located in northwest Connecticut, USA. The three forests differed in soil parent material and canopy tree species composition. At all three sites, amino acids were released from soil organic …

Diverse Spatial, Temporal, And Sexual Expression Of Recently Duplicated Androgen-Binding Protein Genes In Mus Musculus, Christina M. Laukaitis, Stephen R. Dlouhy, Richard D. Emes, Chris P. Ponting, Robert C. Karn

Scholarship and Professional Work - LAS

Background

The genes for salivary androgen-binding protein (ABP) subunits have been evolving rapidly in ancestors of the house mouse Mus musculus, as evidenced both by recent and extensive gene duplication and by high ratios of nonsynonymous to synonymous nucleotide substitution rates. This makes ABP an appropriate model system with which to investigate how recent adaptive evolution of paralogous genes results in functional innovation (neofunctionalization).

Results

It was our goal to find evidence for the expression of as many of the Abp paralogues in the mouse genome as possible. We observed expression of six Abpa paralogues and five Abpbg paralogues …

Descriptive Ecology Of A Turtle Assemblage In An Urban Landscape, Conner C. A, B A. Douthitt, Travis J. Ryan

Scholarship and Professional Work - LAS

We studied turtle populations inhabiting a canal and a lake (both man-made) within a heavily disturbed, urban setting. Six aquatic and semi-aquatic turtle species were collected in both habitats: spiny softshell turtle (Apolone spinifera), painted turtle (Chrysemys picta), common snapping turtle (Chelydra serpentina), common map turtle (Graptemys geographica), common musk turtle (Sternotherus odoratus) and red-eared slider (Trachemys scripta). While G. geographica was the most common species in the canal habitat, T. scripta was most common in the lake habitat. We describe patterns of sexual size dimorphism and sex ratios for the three most abundant species (G. geographica, T. scripta and …

Cortactin Regulates Cell Migration Via Activation Of N-Wasp, Jennifer Kowalski, C. Egile, S. Gil, S. B. Snapper, R. Li, S. M. Thomas

Scholarship and Professional Work - LAS

Cortactin is an actin-associated scaffolding protein that regulates cell migration. Amplification of the human gene, EMS1, has been detected in breast, head and neck tumors, where it correlates with increased invasiveness. Cortactin can regulate actin dynamics directly via its N-terminal half, which can bind and activate the Arp2/3 complex. The C-terminal portion of cortactin, however, is thought to have limited function in its regulation of the actin polymerization machinery. In this report, we identify a role for the cortactin C-terminus in regulating cell migration and, more specifically, actin dynamics. Overexpression of either full-length cortactin or cortactin C-terminus is sufficient to …

Of Looks, Laws And Lawns: How Human Aesthetic Preferences Influence Landscape Management, Public Policies And Urban Ecosystems, Loren B. Byrne

Arts & Sciences Faculty Publications

No abstract provided.

Changes In Antioxidative Enzymes Of Young And Mature Leaves Of Tomato Seedlings Under Drought Stress, Serpi̇l Ünyayar, Fazi̇let Özlem Çeki̇ç

Turkish Journal of Biology

The effects of exogenous abscisic acid (ABA) on antioxidant enzymes of young and mature leaves of 4-week old Lycopersicon esculentum cv. Ailsa Craig and ABA-deficient mutant, notabilis, were investigated under drought stress. Although ABA induced increases in ascorbate peroxidase (APX), glutathione reductase (GR) and catalase (CAT) activities in drought-stressed young leaves of notabilis, CAT activities remained unchanged in both ABA-treated young and mature leaves of Ailsa Craig under drought. Superoxide dismutase (SOD) activity did not substantially increase in notabilis or Ailsa Craig in all treatments. APX activity significantly increased in ABA-, drought- and drought+ABA- treated young leaves of notabilis. These …

Identification Of Neuronal Enhancers Of The Proopiomelanocortin Gene By Transgenic Mouse Analysis And Phylogenetic Footprinting, Flavio S. J. De Souza, Andrea M. Santangelo, Viviana Bumaschny, Marıa Elena Avale, James L. Smart, Malcolm J. Low, Marcelo Rubinstein

Faculty Publications - Department of Biological & Molecular Science

The proopiomelanocortin (POMC) gene is expressed in the pituitary and arcuate neurons of the hypothalamus. POMC arcuate neurons play a central role in the control of energy homeostasis, and rare loss of function mutations in POMC cause obesity. Moreover, POMC is the prime candidate gene within a highly significant quantitative trait locus on chromosome 2 associated with obesity traits in several human populations. Here, we identify two phylogenetically conserved neuronal POMC enhancers designated nPE1 (600 bp) and nPE2 (150 bp) located approximately 10 to 12 kb upstream of mammalian POMC transcriptional units. We show that mouse or human genomic regions …

Aerodynamics Of The Hovering Hummingbird, Douglas R. Warrick, Bret W. Tobalske, Donald R. Powers

Faculty Publications - Department of Biological & Molecular Science

Despite profound musculoskeletal differences, hummingbirds (Trochilidae) are widely thought to employ aerodynamic mechanisms similar to those used by insects. The kinematic symmetry of the hummingbird upstroke and downstroke has led to the assumption that these halves of the wingbeat cycle contribute equally to weight support during hovering, as exhibited by insects of similar size. This assumption has been applied, either explicitly or implicitly, in widely used aerodynamic models, and in a variety of empirical tests. Here we provide measurements of the wake of hovering rufous hummingbirds (Selasphorus rufus) obtained with digital particle image velocimetry that show force asymmetry: hummingbirds produce …

Calmodulin-Dependent Kinase Kinase/Calmodulin Kinase I Activity Gates Extracellular-Regulated Kinase-Dependent Long-Term Potentiation, John M. Schmitt, Eric S. Guire, Takeo Saneyoshi, Thomas R. Soderling

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

Preservation Of Eumelanin Hair Pigmentation In Proopiomelanocortin-Deficient Mice On A Nonagouti (A/A) Genetic Background, Andrzej Slominski, Przemyslaw M. Plonka, Alexander Pisarchik, James L. Smart, Virgine Tolle, Jacobo Wortsman, Malcolm J. Low

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

Nocturnal Shift In The Antipredator Response To Predator-Diet Cues In Laboratory And Field Trials, Aaron M. Sullivan, Dale M. Madison, John C. Maerz

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

Field Evidence And Isolation Of An Amphibian Male-Male Sexual Repellent, Jason R. Rohr, Daesik Park, Aaron M. Sullivan, Malachy Mckenna, Catherine R. Propper, Dale M. Madison

Faculty Publications - Department of Biological & Molecular Science

Operational sex ratio (OSR) has been traditionally thought of as a force imposing competition for mates rather than also a cue used to regulate the intrasexual competition individuals encounter. To assess whether eastern red-spotted newts, Notophthalmus viridescens, could appropriately compare OSRs, we quantified field responses to traps containing four males, a sexually receptive female, four males plus a female, or nothing as a control. Early in the breeding season, males from two populations chose competitive mating opportunities over no mating opportunity at all, but generally preferred less competitive mating prospects. Later in the breeding season, as the OSR of …

Effects Of Endogenous Steroid Hormone Levels On Annual Survival In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Samrrah A. Raouf, Linda C. Smith, John C. Wingfield

School of Biological Sciences: Faculty Publications

The hormone corticosterone is an important part of animals’ response to environmental stress, modulating short-term adaptive changes in behavior and physiology. The hormone testosterone is also critical, especially for males, in regulating the expression of sexual behavior and parental care. These hormones can have costly consequences, however, and within populations individuals show variation in endogenous levels of both corticosterone and testosterone. We studied how annual survival varied as a function of natural levels of these hormones in colonially breeding Cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, USA, in 2000–2003. We sampled hormone levels of birds caught at colonies …

Testosterone And Group Size In Cliff Swallows: Testing The “Challenge Hypothesis” In A Colonial Bird, Linda C. Smith, Samrrah A. Raouf, Mary Bomberger Brown, John C. Wingfield, Charles R. Brown

School of Biological Sciences: Faculty Publications

The “challenge hypothesis” states that increases in testosterone levels of male animals during the breeding season are directly related to the extent of intrasexual competition for resources or mates that they experience. Although often tested in territorial species, the challenge hypothesis has not been evaluated for colonial animals that live in groups of different sizes and that thus experience different intensities of intrasexual competition. We measured circulating testosterone levels of male and female cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, where these birds nest in colonies of widely different sizes. Males had significantly higher testosterone levels than females, …

Between-Group Transmission Dynamics Of The Swallow Bug, Oeciacus Vicarius, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

The parasitic cimicid swallow bug, Oeciacus vicarius, is the principal invertebrate vector for Buggy Creek virus (BCRV) and has also been associated with Venezuelan equine encephalitis virus. To help understand the spread of this vector, we experimentally measured the transmission of O. vicarius between groups (colonies) of its main host, the cliff swallow (Petrochelidon pyrrhonota), in the field. Transmission of bugs between colonies varied significantly with year, size of the colony, and week within the season. Bug immigration into sites tended to peak in mid-summer. Swallow nests in larger colonies had more consistent rates of bug introduction than …

Characterization Of Different Crystal Forms Of The Α-Glucosidase Mala From Sulfolobus Solfataricus, Heidi Asschenfeldt Ernst, Martin Willemoës, Leila Lo Leggio, Gordon Leonard, Paul H. Blum, Sine Larsen

School of Biological Sciences: Faculty Publications

MalA is an _-glucosidase from the hyperthermophilic archaeon Sulfolobus

solfataricus. It belongs to glycoside hydrolase family 31, which includes several

medically interesting α-glucosidases. MalA and its selenomethionine derivative

have been overproduced in Escherichia coli and crystallized in four different

crystal forms. Microseeding was essential for the formation of good-quality

crystals of forms 2 and 4. For three of the crystal forms (2, 3 and 4) full data sets

could be collected. The most suitable crystals for structure determination are the

monoclinic form 4 crystals, belonging to space group P21, from which data sets

extending to 2.5 Å resolution …

Upf1p, A Highly Conserved Protein Required For Nonsense-Mediated Mrna Decay, Interacts With The Nuclear Pore Proteins Nup100p And Nup116p, Tara Nazarenus, Rebecca Cedarberg, Ryan Bell, Joseph Cheatle, Amanda Forch, Alexis Haifley, Ann Hou, Bessie Wanja Kebaara, Christina Shields, Kate Stoysich, Rachel Taylor, Audrey L. Atkin

School of Biological Sciences: Faculty Publications

Saccharomyces cerevisiae Upf1p is a 971-amino-acid protein that is required for the nonsense-mediated mRNA decay (NMD) pathway, a pathway that degrades mRNAs with premature translational termination codons. We have identified a two-hybrid interaction between Upf1p and the nuclear pore (Nup) proteins, Nup100p and Nup116p. Both nucleoporins predominantly localize to the cytoplasmic side of the nuclear pore and participate in mRNA transport. The two-hybrid interaction between Upf1p and the nuclear pore proteins, Nup100p and Nup116p, is dependent on the presence of the C-terminal 158 amino acids of Upf1p. Nup100p and Nup116p can be coimmunoprecipitated from whole-cell extracts with Upf1p, confirming in …

Intra-Guild Compensation Regulatesspecies Richness In Desert Rodents, J. Goheen, Ethan P. White, S.K. Morgan Ernest, J. H. Brown

Biology Faculty Publications

Evidence from numerous studies suggests that species richness is an emergent property of local communities. The maintenance of species richness, despite changes in species composition and environmental conditions, requires compensatory colonization and extinction events with species coming from a regional pool. Using long-term data from a rodent community in the Chihuahuan Desert, we use randomization methods to test the null hypothesis that changes in species richness occur randomly. We find that the dynamics of species richness differ significantly from a random process, and that these nonrandom dynamics occur largely within the most speciose guild. Finally, we propose a general framework …

Evidence For A General Species Time Arearelationship, P. B. Adler, Ethan P. White, W. K. Lauenroth, D. M. Kaufman, A. Rassweiler, J. A. Rusak

Biology Faculty Publications

The species-area relationship (SAR) plays a central role in biodiversity research, and recent work has increased awareness of its temporal analog, the species-time relationship (STR). Here we provide evidence for a general species-time-area-relationship (STAR), in which species number is a function of the area and time span of sampling, as well as their interaction. For eight assemblages ranging from lake zooplankton to desert rodents, this model outperformed a sampling-based model and two simpler models in which area and time had independent effects. In every case the interaction term was negative, meaning that rates of species accumulation in space decreased with …

Condensed Protocol For Competent Cell Preparation And Transformation Of The Methylotrophic Yeast Pichia Pastoris, Joan Lin-Cereghino, William Wong, See Xiong, William Giang, Linda Luong, Jane Vu, Sabrina Johnson, Geoff P. Lin-Cereghino

College of the Pacific Faculty Articles

No abstract provided.

Controls On Nitrogen Cycling In Terrestrial Ecosystems: A Synthetic Analysis Of Literature Data, M. S. Booth, E. Rastetter, John M. Stark

Biology Faculty Publications

Isotope pool dilution studies are increasingly reported in the soils and ecology literature as a means of measuring gross rates of nitrogen (N) mineralization, nitrification, and inorganic N assimilation in soils. We assembled data on soil characteristics and gross rates from 100 studies conducted in forest, shrubland, grassland, and agricultural systems to answer the following questions: What factors appear to be the major drivers for production and consumption of inorganic N as measured by isotope dilution studies? Do rates or the relationships between drivers and rates differ among ecosystem types? Across a wide range of ecosystems, gross N mineralization is …

Trehalose Loading Through The Mitochondrial Permeability Transition Pore Enhances Desiccation Tolerance In Rat Liver Mitochondria., Xiang-Hong Liu, Alptekin Aksan, Michael Menze, Steven Hand, Mehmet Toner

Faculty and Staff Scholarship

Trehalose has extensively been used to improve the desiccation tolerance of mammalian cells. To test whether trehalose improves desiccation tolerance of mammalian mitochondria, we introduced trehalose into the matrix of isolated rat liver mitochondria by reversibly permeabilizing the inner membrane using the mitochondrial permeability transition pore (MPTP). Measurement of the trehalose concentration inside mitochondria using high perfOrmance liquid chromatography showed that the sugar permeated rapidly into the matrix upon opening the MPTP. The concentration of intra matrix trehalose reached 0.29 mmoVmg protein (-190 mM) in 5 min. Mitochondria, with and without trehalose loaded into the matrix, were desiccated in a …

The Flood Pulse In A Semi-Arid Riparian Forest:Metabolic And Biogeochemical Responses To Inter-Flood Interval, H. M. Valett, Michelle A. Baker, J. A. Morrice, C. S. Crawford, M. C. Molles, C. N. Dahm, D. L. Moyer, J. R. Thibault

Biology Faculty Publications

Flood pulse inundation of riparian forests alters rates of nutrient retention and organic matter processing in the aquatic ecosystems formed in the forest interior. Along the Middle Rio Grande (New Mexico, USA), impoundment and levee construction have created riparian forests that differ in their inter-flood intervals (IFIs) because some floodplains are still regularly inundated by the flood pulse (i.e., connected), while other floodplains remain isolated from flooding (i.e., disconnected). This research investigates how ecosystem responses to the flood pulse relate to forest IFI by quantifying nutrient and organic matter dynamics in the Rio Grande floodplain during three years of experimental …

North American Watersnakes: A Natural History, Alan H. Savitzky

Biology Faculty Publications

No abstract provided.

Body Size, Energy Use, And Community Structure Of Small Mammals, S.K. Morgan Ernest

Biology Faculty Publications

Body size has long been hypothesized to play a major role in community structure and dynamics. Two general hypotheses exist for how resources are distributed among body sizes: (1) resources are equally available and uniformly utilized across body sizes and (2) resources are differentially available to organisms of different body sizes, resulting in a nonuniform or modal distribution. It has also been predicted that the distri-bution of body sizes of species in a community should reflect the underlying availability of resources, with the emergence of aggregations of species around specific body sizes. I examined the relationship between energy utilization, body …

Molecular Identification, Distribution And Ecology Of Larval Malaria Mosquitoes In Carrasco/Chapare Valleys, Bolivia, Reema Paudel

Masters Theses

The purpose of this study was to address the ecological differentiation of anopheline mosquitoes at the level of breeding sites in an area where species diversity is high, malaria is endemic, and the ecology of the area is complex. Fifty six sampling sites in the Carrasco/Chapare Valleys, Bolivia were sampled in May 2003 for mosquito larvae and pupae, water quality parameters, breeding water habitat type, vegetation, and altitude. Multiplex polymerase chain reaction of up to 50 samples from each collection site identified six species in the subgenus Nyssorhynchus, comprising 62% of all samples (n = 2,708): A. triannulatus (18%), A. …

Land-Use Changes And Stream Productivity: Effects On Stream Communities And Food-Chain Length, Christopher A. North

Masters Theses

In recent years stream ecologists have come to realize that in order to better understand the processes that occur within streams it is important to incorporate some knowledge of the surrounding landscape into their studies. Previous work on Hurricane Creek indicated that agricultural activities and the proportion of cropland has an impact on stream water chemistry and community metabolism within Hurricane Creek, Illinois. Thus, this study examined stream community composition and food-chain length to ascertain the effects of water quality differences resulting from agricultural land-use practices. The four sites chosen for this study on Hurricane Creek were sampled four times …

Seasonal Movements And Habitat Selection Of Raccoons In A Grassland-Agricultural Landscape, Roberta K. Newbury

Masters Theses

Raccoon (Procyon lotor) populations are very high in Illinois due in part to low pelt value and reduced hunting pressure (Gehrt et al., 2002); furthermore, Illinois' agricultural landscape is conducive to high raccoon densities. Such agricultural areas are known to provide a large, reliable food source for raccoons (Pedlar et al., 1997), and higher predator abundance (e.g. raccoons) at northern latitudes may reflect a greater abundance in cropland (Dijak and Thompson, 2000). Other factors known to increase raccoon numbers are edge effects due to habitat fragmentation and the suppression or eradication of top predators (Soulé et al., 1988; Pedlar et …

Benthic Algal Community Structure And Bioaccumulation Of Mercury In A Coastal Watershed, Lucie Novoveska

Masters Theses

Largemouth bass in the Fish River watershed of coastal Alabama are known to contain relatively high concentrations of mercury (>1 µg g¹). g the source of which is unknown. I used benthic microalgal assemblages in effort to assess spatial distribution of mercury in the Fish River and its tributaries. Artificial substrates were deployed for 3-week exposure periods at 13 sites on 4 separate occasions. When analyzed by cold vapor atomic absorption spectroscopy. mercury concentrations in periphyton ranged from 0.066 µg g (Pensacola Branch) to 0.493 µg g¹ (Barner Branch). Principal component analysis indicated that physical and chemical environments among …

Resilience Of An Amphibian Community Following The Removal Of Introduced Fish, Leroy J. Walston

Masters Theses

Introduced species have become one of the most important anthropogenic impacts in aquatic ecosystems and are implicated in the declines of many native amphibian populations. Despite the effects of introduced species on amphibian populations, there is little information concerning the responses of amphibians following the removal of introduced fish. I conducted a field experiment to assess the amphibian community-level responses to the removal of introduced fish, and determine the effects of fish removal on smallmouth salamander (Ambystoma texanum) larval dynamics. Species diversity of the amphibian community and smallmouth salamander juvenile recruitment improved following the removal of fish. My results indicate …