Biology Commons^™

Activated Rhoa Binds To The Pleckstrin Homology (Ph) Domain Of Pdz-Rhogef, A Potential Site For Autoregulation, Zhe Chen, Frank Medina, Mu-Ya Liu, Celestine Thomas, Stephen R. Sprang, Paul C. Sternweis

Biological Sciences Faculty Publications

Guanine nucleotide exchange factors (GEFs) catalyze exchange of GDP for GTP by stabilizing the nucleotide-free state of the small GTPases through their Dbl homology/pleckstrin homology (DH.PH) domains. Unconventionally, PDZ-RhoGEF (PRG), a member of the RGS-RhoGEFs, binds tightly to both nucleotide-free and activated RhoA (RhoA.GTP). We have characterized the interaction between PRG and activated RhoA and determined the structure of the PRG-DH.PH-RhoA.GTPgammaS (guanosine 5'-O-[gamma-thio]triphosphate) complex. The interface bears striking similarity to a GTPase-effector interface and involves the switch regions in RhoA and a hydrophobic patch in PRG-PH that is conserved among all Lbc RhoGEFs. The two surfaces that bind activated and …

The Interpretation Of Habitat Preference Metrics Under Use–Availability Designs, Hawthorne L. Beyer, Daniel T. Haydon, Juan M. Morales, Jacqueline L. Frair, Mark Hebblewhite, Michael Mitchell, Jason Matthiopoulos

Biological Sciences Faculty Publications

Models of habitat preference are widely used to quantify animal–habitat relationships, to describe and predict differential space use by animals, and to identify habitat that is important to an animal (i.e. that is assumed to influence fitness). Quantifying habitat preference involves the statistical comparison of samples of habitat use and availability. Preference is therefore contingent upon both of these samples. The inferences that can be made from use versus availability designs are influenced by subjectivity in defining what is available to the animal, the problem of quantifying the accessibility of available resources and the framework in which preference is modelled. …

Resolving Issues Of Imprecise And Habitat-Biased Locations In Ecological Analyses Using Gps Telemetry Data, Jacqueline L. Frair, John Fieberg, Mark Hebblewhite, Francesca Cagnacci, Nicholas J. Decesare, Luca Pedrotti

Biological Sciences Faculty Publications

Global positioning system (GPS) technologies collect unprecedented volumes of animal location data, providing ever greater insight into animal behaviour. Despite a certain degree of inherent imprecision and bias in GPS locations, little synthesis regarding the predominant causes of these errors, their implications for ecological analysis or solutions exists. Terrestrial deployments report 37 per cent or less non-random data loss and location precision 30 m or less on average, with canopy closure having the predominant effect, and animal behaviour interacting with local habitat conditions to affect errors in unpredictable ways. Home-range estimates appear generally robust to contemporary levels of location imprecision …

Distinguishing Technology From Biology: A Critical Review Of The Use Of Gps Telemetry Data In Ecology, Mark Hebblewhite, Daniel T. Haydon

Biological Sciences Faculty Publications

In the past decade, ecologists have witnessed vast improvements in our ability to collect animal movement data through animal-borne technology, such as through GPS or ARGOS systems. However, more data does not necessarily yield greater knowledge in understanding animal ecology and conservation. In this paper, we provide a review of the major benefits, problems and potential misuses of GPS/Argos technology to animal ecology and conservation. Benefits are obvious, and include the ability to collect fine-scale spatio-temporal location data on many previously impossible to study animals, such as ocean-going fish, migratory songbirds and long-distance migratory mammals. These benefits come with significant …

Correlation And Studies Of Habitat Selection: Problem, Red Herring Or Opportunity?, John Fieberg, Jason Matthiopoulos, Mark Hebblewhite, Mark S. Boyce, Jacqueline L. Frair

Biological Sciences Faculty Publications

With the advent of new technologies, animal locations are being collected at ever finer spatio-temporal scales. We review analytical methods for dealing with correlated data in the context of resource selection, including post hoc variance inflation techniques, ‘two-stage’ approaches based on models fit to each individual, generalized estimating equations and hierarchical mixed-effects models. These methods are applicable to a wide range of correlated data problems, but can be difficult to apply and remain especially challenging for use–availability sampling designs because the correlation structure for combinations of used and available points are not likely to follow common parametric forms. We also …

Habitat–Performance Relationships: Finding The Right Metric At A Given Spatial Scale, Jean-Michel Gaillard, Mark Hebblewhite, Anne Loison, Mark Fuller, Roger Powell, Mathieu Basille, Bram Van Moorter

Biological Sciences Faculty Publications

The field of habitat ecology has been muddled by imprecise terminology regarding what constitutes habitat, and how importance is measured through use, selection, avoidance and other bio-statistical terminology. Added to the confusion is the idea that habitat is scale-specific. Despite these conceptual difficulties, ecologists have made advances in understanding ‘how habitats are important to animals’, and data from animal-borne global positioning system (GPS) units have the potential to help this clarification. Here, we propose a new conceptual framework to connect habitats with measures of animal performance itself—towards assessing habitat–performance relationship (HPR). Long-term studies will be needed to estimate consequences of …

Plant Neighbor Identity Influences Plant Biochemistry And Physiology Related To Defense, Amanda K. Broz, Corey D. Broeckling, Clelia De-La-Peña, Matthew R. Lewis, Erick Greene, Ragan M. Callaway, Lloyd W. Sumner, Jorge M. Vivanco

Biological Sciences Faculty Publications

Background: Chemical and biological processes dictate an individual organism's ability to recognize and respond to other organisms. A small but growing body of evidence suggests that plants may be capable of recognizing and responding to neighboring plants in a species specific fashion. Here we tested whether or not individuals of the invasive exotic weed, Centaurea maculosa, would modulate their defensive strategy in response to different plant neighbors. Results: In the greenhouse, C. maculosa individuals were paired with either conspecific (C. maculosa) or heterospecific (Festuca idahoensis) plant neighbors and elicited with the plant defense signaling molecule methyl jasmonate to mimic insect …

Alpha-Synuclein Delays Endoplasmic Reticulum (Er)-To-Golgi Transport In Mammalian Cells By Antagonizing Er/Golgi Snares, Nandhakumar Thayanidhi, Jared R. Helm, Deborah C. Nycz, Marbin Bentley, Yingjian Liang, Jesse C. Hay

Biological Sciences Faculty Publications

Toxicity of human alpha-synuclein when expressed in simple organisms can be suppressed by overexpression of endoplasmic reticulum (ER)-to-Golgi transport machinery, suggesting that inhibition of constitutive secretion represents a fundamental cause of the toxicity. Whether similar inhibition in mammals represents a cause of familial Parkinson's disease has not been established. We tested elements of this hypothesis by expressing human alpha-synuclein in mammalian kidney and neuroendocrine cells and assessing ER-to-Golgi transport. Overexpression of wild type or the familial disease-associated A53T mutant alpha-synuclein delayed transport by up to 50%; however, A53T inhibited more potently. The secretory delay occurred at low expression levels and …

An Antibody Directed Against The Fusion Peptide Of Junin Virus Envelope Glycoprotein Gpc Inhibits Ph-Induced Membrane Fusion, Joanne York, Jody D. Berry, Ute Stroeher, Qunnu Li, Heinz Feldmann, Min Lu, Meg Trahey, Jack H. Nunberg

Biological Sciences Faculty Publications

The arenavirus envelope glycoprotein (GPC) initiates infection in the host cell through pH-induced fusion of the viral and endosomal membranes. As in other class I viral fusion proteins, this process proceeds through a structural reorganization in GPC in which the ectodomain of the transmembrane fusion subunit (G2) engages the host cell membrane and subsequently refolds to form a highly stable six-helix bundle structure that brings the two membranes into apposition for fusion. Here, we describe a G2-directed monoclonal antibody, F100G5, that prevents membrane fusion by binding to an intermediate form of the protein on the fusion pathway. Inhibition of syncytium …

Testing Hypotheses For Exotic Plant Success: Parallel Experiments In The Native And Introduced Ranges, Jennifer L. Williams, Harald Auge, John L. Maron

Biological Sciences Faculty Publications

A central question in ecology concerns how some exotic plants that occur at low densities in their native range are able to attain much higher densities where they are introduced. This question has remained unresolved in part due to a lack of experiments that assess factors that affect the population growth or abundance of plants in both ranges. We tested two hypotheses for exotic plant success: escape from specialist insect herbivores and a greater response to disturbance in the introduced range. Within three introduced populations in Montana, USA, and three native populations in Germany, we experimentally manipulated insect herbivore pressure …

A Dna-Binding Peroxiredoxin Of Coxiella Burnetii Is Involved In Countering Oxidative Stress During Exponential-Phase Growth, Linda D. Hicks, Rahul Raghavan, James M. Battisti, Michael F. Minnick

Biological Sciences Faculty Publications

Coxiella burnetii is a Gram-negative, obligate intracellular bacterial pathogen that resides within the harsh, acidic confines of a lysosome-like compartment of the host cell that is termed a parasitophorous vacuole. In this study, we characterized a thiol-specific peroxidase of C. burnetii that belongs to the atypical 2-cysteine subfamily of peroxiredoxins, commonly referred to as bacterioferritin comigratory proteins (BCPs). Coxiella BCP was initially identified as a potential DNA-binding protein by two-dimensional Southwestern (SW) blots of the pathogen's proteome, probed with biotinylated C. burnetii genomic DNA. Confirmation of the identity of the DNA-binding protein as BCP (CBU_0963) was established by matrix-assisted laser …

A Toolkit For Rapid Gene Mapping In The Nematode Caenorhabditis Briggsae, Daniel C. Koboldt, Julia E. Staisch, Bavithra Thillainathan, Karen Haines, Scott Everet Baird, Helen M. Chamberlin, Eric S. Haag, Raymond D. Miller, Bhagwati P. Gupta

Biological Sciences Faculty Publications

Background

The nematode C. briggsae serves as a useful model organism for comparative analysis of developmental and behavioral processes. The amenability of C. briggsae to genetic manipulations and the availability of its genome sequence have prompted researchers to study evolutionary changes in gene function and signaling pathways. These studies rely on the availability of forward genetic tools such as mutants and mapping markers.

Results

We have computationally identified more than 30,000 polymorphisms (SNPs and indels) in C. briggsae strains AF16 and HK104. These include 1,363 SNPs that change restriction enzyme recognition sites (snip-SNPs) and 638 indels that range between 7 …

Evaluating Forensic Dna Evidence, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

Establishing Parameters For Objective Interpretation Of Dna Profile Evidence, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

Funding Needed For Assessments Of Weed Biological Control, John L. Maron, Dean E. Pearson, Stephen M. Hovick, Walter P. Carson

Biological Sciences Faculty Publications

No abstract provided.

Isoform-Specific Regulation And Localization Of The Coxsackie And Adenovirus Receptor In Human Airway Epithelia, Katherine J.D.A. Excoffon, Nicholas D. Gansemer, Matthew E. Mobily, Philip H. Karp, Kalpaj R. Parekh, Joseph Zabner

Biological Sciences Faculty Publications

Adenovirus is an important respiratory pathogen. Adenovirus fiber from most serotypes co-opts the Coxsackie-Adenovirus Receptor (CAR) to bind and enter cells. However, CAR is a cell adhesion molecule localized on the basolateral membrane of polarized epithelia. Separation from the lumen of the airways by tight junctions renders airway epithelia resistant to inhaled adenovirus infection. Although a role for CAR in viral spread and egress has been established, the mechanism of initial respiratory infection remains controversial. CAR exists in several protein isoforms including two transmembrane isoforms that differ only at the carboxy-terminus (CAR^Ex7 and CAR^Ex8). We found low-level …

Vesicular Calcium Regulates Coat Retention, Fusogenicity, And Size Of Pre-Golgi Intermediates, Marvin Bentley, Deborah C. Nycz, Ashwini Joglekar, Ismene Fertschai, Roland Malli, Wolfgang F. Graier, Jesse C. Hay

Biological Sciences Faculty Publications

The significance and extent of Ca(2+) regulation of the biosynthetic secretory pathway have been difficult to establish, and our knowledge of regulatory relationships integrating Ca(2+) with vesicle coats and function is rudimentary. Here, we investigated potential roles and mechanisms of luminal Ca(2+) in the early secretory pathway. Specific depletion of luminal Ca(2+) in living normal rat kidney cells using cyclopiazonic acid (CPA) resulted in the extreme expansion of vesicular tubular cluster (VTC) elements. Consistent with this, a suppressive role for vesicle-associated Ca(2+) in COPII vesicle homotypic fusion was demonstrated in vitro using Ca(2+) chelators. The EF-hand-containing protein apoptosis-linked gene 2 …

Use Of Rpsl As A Counterselectable Marker In Borrelia Burgdorferi, Dan Drecktrah, Miles J. Douglas, D. Scott Samuels

Biological Sciences Faculty Publications

We have demonstrated that rpsL, encoding the S12 protein of the small ribosomal subunit, can be used as a counterselectable marker in Borrelia burgdorferi, the causative agent of Lyme disease. Mutations in rpsL confer streptomycin resistance. Streptomycin susceptibility is dominant in an rpsL merodiploid, and streptomycin selects for the loss of wild-type rpsL carried in trans. This is the first description of a counterselectable marker in B. burgdorferi.

Probable Causes Of Increasing Brucellosis In Free-Ranging Elk Of The Greater Yellowstone Ecosystem, P. C. Cross, E. K. Cole, A. P. Dobson, W. H. Edwards, K. L. Hamlin, Gordon Luikart, A. D. Middleton, B. M. Scurlock, P. J. White

Biological Sciences Faculty Publications

While many wildlife species are threatened, some populations have recovered from previous Overexploitation, and data linking these population increases with disease dynamics are limited. We present data suggesting that free-ranging elk (Cervus elaphus) are a maintenance host for Brucella abortus in new areas of the Greater Yellowstone Ecosystem (GYE). Brucellosis seroprevalence in free-ranging elk increased from 0-7% in 1991-1992 to 8 20% in 2006-2007 in four of six herd units around the GYE. These levels of brucellosis are comparable to some herd units where elk are artificially aggregated on supplemental feeding grounds. There are several possible mechanisms for this increase …

Merits And Limits Of Ecosystem Protection For Conserving Wild Salmon In A Northern Coastal British Columbia River, Aaron C. Hill, Thomas S. Bansak, Bonnie K. Ellis, Jack Arthur Stanford

Biological Sciences Faculty Publications

Loss and degradation of freshwater habitat reduces the ability of wild salmon populations to endure other anthropogenic stressors such as climate change, harvest, and interactions with artificially propagated fishes. Preservation of pristine salmon rivers has thus been advocated as a cost-effective way of sustaining wild Pacific salmon populations. We examine the value of freshwater habitat protection in conserving salmon and fostering resilience in the Kitlope watershed in northern coastal British Columbia—a large (3186 km²) and undeveloped temperate rainforest ecosystem with legislated protected status. In comparison with other pristine Pacific Rim salmon rivers we studied, the Kitlope is characterized …

Functional Convergence In Reduced Genomes Of Bacterial Symbionts Spanning 200 My Of Evolution, John P. Mccutcheon, Nancy A. Moran

Biological Sciences Faculty Publications

The main genomic changes in the evolution of host-restricted microbial symbionts are ongoing inactivation and loss of genes combined with rapid sequence evolution and extreme structural stability; these changes reflect high levels of genetic drift due to small population sizes and strict clonality. This genomic erosion includes irreversible loss of genes in many functional categories and can include genes that underlie the nutritional contributions to hosts that are the basis of the symbiotic association. Candidatus Sulcia muelleri is an ancient symbiont of sap-feeding insects and is typically coresident with another bacterial symbiont that varies among host subclades. Previously sequenced Sulcia …

Are Forested Buffers An Effective Conservation Strategy For Riparian Fauna? An Assessment Using Meta-Analysis, Laurie B. Marczak, Takashi Sakamaki, Shannon L. Turvey, Isabelle Deguise, Sylvia L. R. Wood, John S. Richardson

Biological Sciences Faculty Publications

Historically, forested riparian buffers have been created to provide protection for aquatic organisms and aquatic ecosystem functions. Increasingly, new and existing riparian buffers are being used also to meet terrestrial conservation requirements. To test the effectiveness of riparian buffers for conserving terrestrial fauna, we conducted a meta-analysis using published data from 397 comparisons of species abundance in riparian buffers and unharvested (reference) riparian sites. The response of terrestrial species to riparian buffers was not consistent between taxonomic groups; bird and arthropod abundances were significantly greater in buffers relative to unharvested areas, whereas amphibian abundance decreased. Edge-preferring species were more abundant …

Cellular And Molecular Dissection Of Pluripotent Adult Somatic Stem Cells In Planarians, Norito Shibata, Labib Rouhana, Kiyokazu Agata

Biological Sciences Faculty Publications

Freshwater planarians, Plathelminthes, have been an intriguing model animal of regeneration studies for more than 100 years. Their robust regenerative ability is one of asexual reproductive capacity, in which complete animals develop from tiny body fragments within a week. Pluripotent adult somatic stem cells, called neoblasts, assure this regenerative ability. Neoblasts give rise to not only all types of somatic cells, but also germline cells. During the last decade, several experimental techniques for the analysis of planarian neoblasts at the molecular level, such as in situ hybridization, RNAi and fluorescence activated cell sorting, have been established. Moreover, information about genes …

Small-Mammal Seed Predation Limits The Recruitment And Abundance Of Two Perennial Grassland Forbs, Mary Bricker, Dean Pearson, John L. Maron

Biological Sciences Faculty Publications

Although post-dispersal seed predators are common and often reduce seed density, their influence on plant population abundance remains unclear. On the one hand, increasing evidence suggests that many plant populations are seed limited, implying that seed predators could reduce plant abundance. On the other hand, it is generally uncertain whether the magnitude of seed limitation imposed by granivores is strong enough to overcome density-dependent processes that could compensate for seed loss at later stages. We examined the impact of seed predation by small mammals, primarily deer mice (Peromyscus maniculatus), on seedling recruitment and subsequent plant establishment of two …

Building A Mechanistic Understanding Of Predation With Gps-Based Movement Data, Evelyn Merrill, Ha˚Kan Sand, Barbara Zimmermann, Heather Mcphee, Nathan Webb, Mark Hebblewhite, Peter Wabakken, Jacqueline L. Frair

Biological Sciences Faculty Publications

Quantifying kill rates and sources of variation in kill rates remains an important challenge in linking predators to their prey. We address current approaches to using global positioning system (GPS)-based movement data for quantifying key predation components of large carnivores. We review approaches to identify kill sites from GPS movement data as a means to estimate kill rates and address advantages of using GPS-based data over past approaches. Despite considerable progress, modelling the probability that a cluster of GPS points is a kill site is no substitute for field visits, but can guide our field efforts. Once kill sites are …

Conservation Status And Habitat Use Of The West Virginia Spring Salamander (Gyrinophilus Subterraneus) And Spring Salamander (G. Porphyriticus) In General Davis Cave, Greenbrier Co., West Virginia, Matthew L. Niemiller, Michael S. Osbourn, Dante B. Fenolio, Thomas K. Pauley, Brian T. Miller, John R. Holsinger

Biological Sciences Faculty Publications

The West Virginia Spring Salamander (Gyrinophilus subterraneus) is one of four obligate cave-dwelling species of plethodontid salamanders found east of the Mississippi River in the United States. This species is endemic to a single cave system; General Davis Cave, in Greenbrier Co., West Virginia, where it is syntopic with the closely-related Spring Salamander (G. porphyriticus). Accordingly, the West Virginia Spring Salamander is a species of critical conservation concern. Because of it's conservation status and lack of data regarding the ecology and life history, particularly about population trends, we present data on relative abundance of and habitat …

Don't Diss Integration: A Comment On Ricklefs's Disintegrating Communities, Rob W. Booker, Ragan M. Callaway, Lohengrin A. Cavieres, Zaal Kikvidze, Christopher J. Lortie, Richard Michalet, Francisco I. Pugnaire, Alfonso Valiente-Banuet, Thomas G. Whitham

Biological Sciences Faculty Publications

No abstract provided.

Evaluating Forensic Dna Evidence, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

E Unibus Plurum: Genomic Analysis Of An Experimentally Evolved Polymorphism In Escherichia Coli, Margie A. Kinnersley, William E. Holben, Frank Rosenzweig

Biological Sciences Faculty Publications

Microbial populations founded by a single clone and propagated under resource limitation can become polymorphic. We sought to elucidate genetic mechanisms whereby a polymorphism evolved in Escherichia coli under glucose limitation and persisted because of cross-feeding among multiple adaptive clones. Apart from a 29 kb deletion in the dominant clone, no large-scale genomic changes distinguished evolved clones from their common ancestor. Using transcriptional profiling on co-evolved clones cultured separately under glucose-limitation we identified 180 genes significantly altered in expression relative to the common ancestor grown under similar conditions. Ninety of these were similarly expressed in all clones, and many of …

Group I Introns And Inteins: Disparate Origins But Convergent Parasitic Strategies, Rahul Raghavan, Michael F. Minnick

Biological Sciences Faculty Publications

No abstract provided.