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Biology Faculty Publications

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Articles 1021 - 1050 of 1366

Full-Text Articles in Biology

Microarray And Cdna Sequence Analysis Of Transcription During Nerve-Dependent Limb Regeneration, James R. Monaghan, Leonard G. Epp, Srikrishna Putta, Robert B. Page, John A. Walker, Chris K. Beachy, Wei Zhu, Gerald M. Pao, Inder M. Verma, Tony Hunter, Susan V. Bryant, David M. Gardiner, Tim T. Harkins, S. Randal Voss Jan 2009

Microarray And Cdna Sequence Analysis Of Transcription During Nerve-Dependent Limb Regeneration, James R. Monaghan, Leonard G. Epp, Srikrishna Putta, Robert B. Page, John A. Walker, Chris K. Beachy, Wei Zhu, Gerald M. Pao, Inder M. Verma, Tony Hunter, Susan V. Bryant, David M. Gardiner, Tim T. Harkins, S. Randal Voss

Biology Faculty Publications

Background

Microarray analysis and 454 cDNA sequencing were used to investigate a centuries-old problem in regenerative biology: the basis of nerve-dependent limb regeneration in salamanders. Innervated (NR) and denervated (DL) forelimbs of Mexican axolotls were amputated and transcripts were sampled after 0, 5, and 14 days of regeneration.

Results

Considerable similarity was observed between NR and DL transcriptional programs at 5 and 14 days post amputation (dpa). Genes with extracellular functions that are critical to wound healing were upregulated while muscle-specific genes were downregulated. Thus, many processes that are regulated during early limb regeneration do not depend upon nerve-derived factors. …


Microarray And Cdna Sequence Analysis Of Transcription During Nerve-Dependent Limb Regeneration, James R. Monaghan, Leonard G. Epp, Srikrishna Putta, Robert B. Page, John A. Walker, Chris K. Beachy, Wei Zhu, Gerald M. Pao, Inder M. Verma, Tony Hunter, Susan V. Bryant, David M. Gardiner, Tim T. Harkins, S. Randal Voss Jan 2009

Microarray And Cdna Sequence Analysis Of Transcription During Nerve-Dependent Limb Regeneration, James R. Monaghan, Leonard G. Epp, Srikrishna Putta, Robert B. Page, John A. Walker, Chris K. Beachy, Wei Zhu, Gerald M. Pao, Inder M. Verma, Tony Hunter, Susan V. Bryant, David M. Gardiner, Tim T. Harkins, S. Randal Voss

Biology Faculty Publications

BACKGROUND: Microarray analysis and 454 cDNA sequencing were used to investigate a centuries-old problem in regenerative biology: the basis of nerve-dependent limb regeneration in salamanders. Innervated (NR) and denervated (DL) forelimbs of Mexican axolotls were amputated and transcripts were sampled after 0, 5, and 14 days of regeneration.

RESULTS: Considerable similarity was observed between NR and DL transcriptional programs at 5 and 14 days post amputation (dpa). Genes with extracellular functions that are critical to wound healing were upregulated while muscle-specific genes were downregulated. Thus, many processes that are regulated during early limb regeneration do not depend upon nerve-derived factors. …


Investigation Of A Fresh African Elephant Carcass By Conspecifics, Christen Merte, Katie Gough, Bruce A. Schulte Jan 2009

Investigation Of A Fresh African Elephant Carcass By Conspecifics, Christen Merte, Katie Gough, Bruce A. Schulte

Biology Faculty Publications

This examination of elephant bones and ivory indicates that elephants show an elevated level of interest in conspecifics over other dead animals. Elephants do not seem to express special interest in dead kin but rather they appear to have a generalized response to injured, dying and deceased conspecifics (Douglas Hamilton et al. 2006, McComb et al. 2006). The present study reports the behaviour of a group of elephants in response to a euthanized adult male elephant that suffered severe wounds inflicted by a conspecific male. Most of the observations from previous studies have been on females and female group members. …


Cuscuta Jepsonii (Convolvulaceae): An Invasive Weed Or An Extinct Endemic?, Mihai Costea, Saša Stefanović Jan 2009

Cuscuta Jepsonii (Convolvulaceae): An Invasive Weed Or An Extinct Endemic?, Mihai Costea, Saša Stefanović

Biology Faculty Publications

Despite their ecological significance, parasitic plants face more conservation challenges than do autotrophic plants. This is especially true for the groups that include weedy or invasive species such as Cuscuta. While approximately half of the Cuscuta (dodders) species may require conservation measures, the genus as a whole is sometimes posted on governmental lists of noxious or quarantine weeds. Our study challenges this stereotype and uses the case of C. jepsonii (Jepson’s dodder) to illustrate the precarious biodiversity and conservation status faced by many dodder species. Until now, Jepson’s dodder has been known only from its type collection. Consequently, its …


Prospecting For Mammalian Chemical Signals Via Solventless Extraction Techniques: An Elephantine Task, Thomas Goodwin, Bruce A. Schulte Jan 2009

Prospecting For Mammalian Chemical Signals Via Solventless Extraction Techniques: An Elephantine Task, Thomas Goodwin, Bruce A. Schulte

Biology Faculty Publications

In contrast to a plethora of known insect pheromones, a paucity of mammalian pheromones has been identified, two of which have been in elephants (Albone, 1984; Brown and Macdonald, 1985; Wyatt, 2003; Burger, 2005). Elephants possess one of the world’s best chemosensory systems, due in no small measure to their prehensile trunk. The trunk is not only the gateway to smelling (primary olfaction), but also the means by which chemical signals are conveyed from their source to the openings of the vomeronasal organ ducts in the roof of the mouth (the flehmen response; secondary olfaction) (Rasmussen, 1999). The late L. …


Field Guide To The Fishes Of Eastern Washington, Allan T. Scholz, Holly J. Mclellan, Judy Mcmillan, Larry Conboy, Michelle Kirkendall, Angela Davis, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics., United States. Bureau Of Land Management. Jan 2009

Field Guide To The Fishes Of Eastern Washington, Allan T. Scholz, Holly J. Mclellan, Judy Mcmillan, Larry Conboy, Michelle Kirkendall, Angela Davis, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics., United States. Bureau Of Land Management.

Biology Faculty Publications

"This book was prepared through a grant from the United States Department of the Interior, Bureau of Land Management (BLM)."


An Introduction To The Biocomplexity Of Sanak Island, Western Gulf Alaska, Hd G. Maschner, M Betts, J Cornell, B Finney, J A. Dunne, Nancy J. Huntly, J W. Jordan, N Misarti, K L. Reedy-Maschner, R Russell Jan 2009

An Introduction To The Biocomplexity Of Sanak Island, Western Gulf Alaska, Hd G. Maschner, M Betts, J Cornell, B Finney, J A. Dunne, Nancy J. Huntly, J W. Jordan, N Misarti, K L. Reedy-Maschner, R Russell

Biology Faculty Publications

The Sanak Biocomplexity Project is a transdisciplinary research effort focused on a small island archipelago 50 km south of the Alaska Peninsula in the western Gulf of Alaska. This team of archaeologists, terrestrial ecologists, social anthropologists, intertidal ecologists, geologists, oceanographers, paleoecologists, and modelers is seeking to understanding the role of the ancient, historic, and modern Aleut in the structure and functioning of local and regional ecosystems. Using techniques ranging from systematic surveys to stable isotope chemistry, long-term shifts in social dynamics and ecosystem structure are present in the context of changing climatic regimes and human impacts. This paper presents a …


Incidence And Post-Pollination Mechanisms Of Nonrandom Mating In Arabidopsis Thaliana, Ann L. Carlson, Megan Telligman, Rob Swanson Jan 2009

Incidence And Post-Pollination Mechanisms Of Nonrandom Mating In Arabidopsis Thaliana, Ann L. Carlson, Megan Telligman, Rob Swanson

Biology Faculty Publications

Compatible pollinations from many differenttaxa display nonrandom mating. Here we describe a systemfor examining questions of nonrandom mating in Arabidopsisthaliana. Using this system, we demonstrate thatArabidopsis thaliana displays nonrandom mating betweendistinct accessions. Statistical analysis of these data demonstratesaspects of both pollen competition and male–female complementarity in these matings. Cytologicalexperiments implicate pollen germination and pollen tubegrowth rates as possible causal factors in these nonrandommating efficiencies.


Lap3, A Novel Plant Protein Required For Pollen Development, Is Essential For Proper Exine Formation, Anna A. Dobritsa, Shuh-Ichi Nishikawa, Daphne Preuss, Ewa Urbanczyk-Wochniak, Lloyd W. Sumner, Adam Hammond, Ann L. Carlson, Rob Swanson Jan 2009

Lap3, A Novel Plant Protein Required For Pollen Development, Is Essential For Proper Exine Formation, Anna A. Dobritsa, Shuh-Ichi Nishikawa, Daphne Preuss, Ewa Urbanczyk-Wochniak, Lloyd W. Sumner, Adam Hammond, Ann L. Carlson, Rob Swanson

Biology Faculty Publications

We isolated lap3-1 and lap3-2 mutants in ascreen for pollen that displays abnormal stigma binding.Unlike wild-type pollen, lap3-1 and lap3-2 pollen exine isthinner, weaker, and is missing some connections betweentheir roof-like tectum structures. We describe the mappingand identification of LAP3 as a novel gene that contains arepetitive motif found in b-propeller enzymes. Insertionmutations in LAP3 lead to male sterility. To investigatepossible roles for LAP3 in pollen development, we assayedthe metabolite profile of anther tissues containing developingpollen grains and found that the lap3-2 defect leadsto a broad range of metabolic changes. The largest changeswere seen in levels of a straight-chain hydrocarbon …


Cyp704b1 Is A Long-Chain Fatty Acid V-Hydroxylase Essential For Sporopollenin Synthesis In Pollen Of Arabidopsis, Anna A. Dobritsa, Jay Shrestha, Marc Morant, Franck Pinot, Michiyo Matsuno, Rob Swanson, Birger Lindberg Møller, Daphne Preuss Jan 2009

Cyp704b1 Is A Long-Chain Fatty Acid V-Hydroxylase Essential For Sporopollenin Synthesis In Pollen Of Arabidopsis, Anna A. Dobritsa, Jay Shrestha, Marc Morant, Franck Pinot, Michiyo Matsuno, Rob Swanson, Birger Lindberg Møller, Daphne Preuss

Biology Faculty Publications

Sporopollenin is the major component of the outer pollen wall (exine). Fatty acid derivatives and phenolics are thought to be itsmonomeric building blocks, but the precise structure, biosynthetic route, and genetics of sporopollenin are poorly understood.Based on a phenotypic mutant screen in Arabidopsis (Arabidopsis thaliana), we identified a cytochrome P450, designatedCYP704B1, as being essential for exine development. CYP704B1 is expressed in the developing anthers. Mutations in CYP704B1result in impaired pollen walls that lack a normal exine layer and exhibit a characteristic striped surface, termed zebraphenotype. Heterologous expression of CYP704B1 in yeast cells demonstrated that it catalyzes v-hydroxylation of long-chainfatty acids, …


Global Chloroplast Phylogeny And Biogeography Of Bracken (Pteridium: Dennstaedtiaceae), Joshua P. Der, J. A. Thomson, J. K. Stratford, Paul G. Wolf Jan 2009

Global Chloroplast Phylogeny And Biogeography Of Bracken (Pteridium: Dennstaedtiaceae), Joshua P. Der, J. A. Thomson, J. K. Stratford, Paul G. Wolf

Biology Faculty Publications

Bracken ferns (genus Pteridium ) represent an ancient species complex with a natural worldwide distribution. Pteridium has historically been treated as comprising a single species, but recent treatments have recognized several related species. Phenotypic plasticity, geographically structured morphological variation, and geographically biased sampling have all contributed to taxonomic confusion in the genus. We sampled bracken specimens worldwide and used variable regions of the chloroplast genome to investigate phylogeography and reticulate evolution within the genus. Our results distinguish two major clades within Pteridium , a primarily northern hemisphere Laurasian/African clade, which includes all taxa currently assigned to P. aquilinum , and …


Hydrologic Control Of Nitrogenremoval, Storage And Export In A Mountain Stream, R. O. Hall Jr., Michelle A. Baker, C. D. Arp, B. J. Koch Jan 2009

Hydrologic Control Of Nitrogenremoval, Storage And Export In A Mountain Stream, R. O. Hall Jr., Michelle A. Baker, C. D. Arp, B. J. Koch

Biology Faculty Publications

Nutrient cycling and export in streams and rivers should vary with flow regime, yet most studies of stream nutrient transformation do not include hydrologic variability. We used a stable isotope tracer of nitrogen (15N) to measure nitrate (NO3-) uptake, storage, and export in a mountain stream, Spring Creek, Idaho, U.S.A. We conducted two tracer tests of 2-week duration during snowmelt and baseflow. Dissolved and particulate forms of 15N were monitored over three seasons to test the hypothesis that stream N cycling would be dominated by export during floods, and storage during low flow. Floods …


Changes In A Tropical Forest Support Metabolic Zero-Sum Dynamics, S.K. Morgan Ernest, Ethan P. White, J. H. Brown Jan 2009

Changes In A Tropical Forest Support Metabolic Zero-Sum Dynamics, S.K. Morgan Ernest, Ethan P. White, J. H. Brown

Biology Faculty Publications

Major shifts in many ecosystem-level properties of tropical forests have been observed, but the processes driving these changes are poorly understood. Over the past two decades, the forest on Barro Colorado Island, Panama (BCI) exhibited a 20% decrease in the number of trees and a 10% increase in average tree diameter. Here we show that these changes are consistent with a zero-sum constraint operating in this forest. Zero-sum constraints result when the total resource use of an ecosystem is limited by available resources. This causes increases in resource use by some groups of organisms to be compensated for by decreases …


Bibliography Of The Frogs Of The Leptodactylus Clade – Adenomera, Hydrolaetare, Leptodactylus, Lithodytes (Amphibia, Anura, Leptodactylidae) Volume 2. Indices, Miriam H. Heyer, W. Ronald Heyer, Rafael O. De Sá Jan 2009

Bibliography Of The Frogs Of The Leptodactylus Clade – Adenomera, Hydrolaetare, Leptodactylus, Lithodytes (Amphibia, Anura, Leptodactylidae) Volume 2. Indices, Miriam H. Heyer, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

The bibliography (Volume 1) is organized alphabetically by last name of the first author. The Species Index, Keyword Index, and Geographic Index are organized by the unique number that EndNote® assigns to each record. To find a reference from the three indices, one must utilize the References by EndNote® Number, listed in numerical order. There is sufficient information associated with the EndNote® numerical order entry to find the specific reference involved in Volume 1 – References.

Complete authors names are used in the EndNote® Number index for the EndNote® records that contain such information. Note that there are some “missing” …


The Tadpole Of Hypsiboas Atlanticus (Anura, Hylidae) From Northeastern Brazil, Filipe A. C. Do Nascimento, Marcelo G. De Lima, Gabriel O. Skuk, Rafael O. De Sá Jan 2009

The Tadpole Of Hypsiboas Atlanticus (Anura, Hylidae) From Northeastern Brazil, Filipe A. C. Do Nascimento, Marcelo G. De Lima, Gabriel O. Skuk, Rafael O. De Sá

Biology Faculty Publications

The tadpole of Hypsiboas atlanticus (Caramaschi & Velosa, 1996) is described from the municipality of Maceió, State of Alagoas, Brazil. At stage 36 the larvae have an overall elliptical body in lateral and dorsal views, oral disc anteroventral, spiracular tube sinistral, and labial tooth row formula 2(1,2)/3(1). The oral disc is surrounded, almost completely (anterior medial gap present) by a single row of marginal papillae. Described tadpoles of the H. punctatus species group can be differentiated by a combined disc oral features. Additional descriptions of H. punctatus (Schneider, 1799) tadpoles from populations throughout South America may be helpful in determining …


7tmrmine: A Web Server For Hierarchical Mining Of 7tmr Proteins, Guoqing Lu, Zhifang Wang, Alan M. Jones, Etsuko N. Moriyama Jan 2009

7tmrmine: A Web Server For Hierarchical Mining Of 7tmr Proteins, Guoqing Lu, Zhifang Wang, Alan M. Jones, Etsuko N. Moriyama

Biology Faculty Publications

Background: Seven-transmembrane region-containing receptors (7TMRs) play central roles in eukaryotic signal transduction. Due to their biomedical importance, thorough mining of 7TMRs from diverse genomes has been an active target of bioinformatics and pharmacogenomics research. The need for new and accurate 7TMR/GPCR prediction tools is paramount with the accelerated rate of acquisition of diverse sequence information. Currently available and often used protein classification methods (e.g., profile hidden Markov Models) are highly accurate for identifying their membership information among already known 7TMR subfamilies. However, these alignment-based methods are less effective for identifying remote similarities, e.g., identifying proteins from highly divergent or possibly …


Summer Burrows Of Ord's Kangaroo Rats (Dipodomys Ordii) In Western Nebraska: Food Content And Structure, Jeremy A. White Jan 2009

Summer Burrows Of Ord's Kangaroo Rats (Dipodomys Ordii) In Western Nebraska: Food Content And Structure, Jeremy A. White

Biology Faculty Publications

Extent of larder hoarding differs among species of kangaroo rats, and limited information is available for food stored in burrows by Ord's kangaroo rat (Dipodomys ordii)—the most widespread species of Dipodomys. I excavated 9 burrows recently used by adult D. ordii during summer in the Sandhill Region of Nebraska. I observed only small quantities of food stored in burrows. Eight of 9 burrows contained segments of sand dropseed (Sporobolus cryptandrus) in limited quantities. These segments consisted of upper leaves with fruits (containing seeds) housed in sheaths. My observations represent the first documentation of D. ordii storing food in burrows under …


Estrogenic Compounds Downstream From Three Small Cities In Eastern Nebraska: Occurrence And Biological Effect, Marlo K. Sellin, Daniel D. Snow, Debbie L. Akerly, Alan S. Kolok Jan 2009

Estrogenic Compounds Downstream From Three Small Cities In Eastern Nebraska: Occurrence And Biological Effect, Marlo K. Sellin, Daniel D. Snow, Debbie L. Akerly, Alan S. Kolok

Biology Faculty Publications

Recent studies have detected estrogenic compounds in surface waters in North America and Europe. Furthermore, the presence of estrogenic compounds in surface waters has been attributed, in some cases, to the discharge of wastewater treatment plant (WWTP) effluent. The primary objective of the current study was to determine if WWTP effluent contributes estrogens to the surface waters of Nebraska. A second objective of this study was to determine if estrogens were found in concentrations sufficient enough to manifest feminizing effects on fish. These objectives were satisfied by deploying polar organic chemical integrative samplers (POCIS) and caged fathead minnows at eight …


Patterning Defects In Silkworm Embryos Analysed Through Cuticle Preparations, Amit Singh, Madhuri Kango-Singh, K. P. Gopinathan Jan 2009

Patterning Defects In Silkworm Embryos Analysed Through Cuticle Preparations, Amit Singh, Madhuri Kango-Singh, K. P. Gopinathan

Biology Faculty Publications

The mulberry silkworm, Bombyx mori, a holometabolous lepidopteran insect, has a metameric body plan. Due to its functional adaptation, B. mori presents some unique deviations in its pal/ern from the evolutionarily advanced dipteran insect, Drosophila melanogaster. Previous studies on mutant phenotype analysis in B. mori have been carried out in late stages of larval development. Here we employ, the cuticle preparation approach during embryonic development to study morphological landmarks associated with B. mori, Eri, another race a/silkworm, and pattern defects associated with Ekp mutant of B.mori. The homeotic mutant Ekp, generates ectopic abdominallegs, a feature …


Differences In Nitrate Uptakeamong Benthic Algal Assemblages In A Mountain Stream, Michelle A. Baker, G. De Guzman Jan 2009

Differences In Nitrate Uptakeamong Benthic Algal Assemblages In A Mountain Stream, Michelle A. Baker, G. De Guzman

Biology Faculty Publications

We evaluated how benthic algal assemblages that vary in composition, richness, and other diversity metrics remove NO 3 -N from the water column of a mountain stream. Ecological theory and empirical studies suggest that ecosystem process rates should increase as richness increases because of niche separation or activity of dominant taxa. Accordingly, we predicted that algal assemblages with highest richness would show the highest rates of NO 3 -N uptake. To test this prediction, we transplanted 225 rocks representing 3 patch types (green, yellow, and brown) that differed macroscopically in algal composition from a lake outflow stream to a lake …


Selective Herbivory By The Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), M P. Stanford, Nancy J. Huntly Jan 2009

Selective Herbivory By The Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), M P. Stanford, Nancy J. Huntly

Biology Faculty Publications

We studied herbivory by the desert woodrat (Neotoma lepida) on Joshua trees (Yucca brevifolia) in the Mojave Desert to determine whether N. lepida fed selectively based on leaf nitrogen content. We measured leaf nitrogen content and the location and amount of herbivory by woodrats on Y. brevifolia trees in southwestern Utah, USA. Neotoma lepida removed the outer tips of leaves (1/3 to 2/3 of total leaf length) but left leaf bases, which had lower nitrogen content, uneaten. Herbivory by N. lepida also was concentrated on rosettes that were oriented south, and these had significantly higher nitrogen content than rosettes that …


Taking Species Abundance Distributions Beyond Individuals, H. Morlon, Ethan P. White, R. S. Etienne, J. L. Green, A. Ostling, D. Alonso, B. J. Enquist, F. He, A. H. Hurlbert, A. E. Magurran, B. A. Maurer, B. J. Mcgill, H. Olff, D. Storch, T. Zillio Jan 2009

Taking Species Abundance Distributions Beyond Individuals, H. Morlon, Ethan P. White, R. S. Etienne, J. L. Green, A. Ostling, D. Alonso, B. J. Enquist, F. He, A. H. Hurlbert, A. E. Magurran, B. A. Maurer, B. J. Mcgill, H. Olff, D. Storch, T. Zillio

Biology Faculty Publications

The species abundance distribution is one of the few “universal” patterns in ecology. Research on this fundamental distribution has been focused to the study of numerical counts, irrespective of the traits of individuals. Here we show that considering a set of Generalized Species Abundance Distributions (GSADs) that encompass several abundance measures, specifically numerical abundance, biomass and resource use can provide novel insights into organizational forces at play in ecological communities. We first leverage a comprehensive dataset to investigate the similarity and difference between GSADs. We then use classical probability theory and allometric scaling laws to explore theoretical linkages among GSADs …


Long-Term Monitoring And Experimentalmanipulation Of A Chihuahuan Desert Ecosystem Near Portal, Arizona, Usa, S.K. Morgan Ernest, T. J. Valone, J. H. Brown Jan 2009

Long-Term Monitoring And Experimentalmanipulation Of A Chihuahuan Desert Ecosystem Near Portal, Arizona, Usa, S.K. Morgan Ernest, T. J. Valone, J. H. Brown

Biology Faculty Publications

Desert ecosystems have long served as model systems in the study of ecological concepts (e.g., competition, resource pulses, top-down/bottom-up dynamics). However, the inherent variability of resource availability in deserts, and hence consumer dynamics, can also make them challenging ecosystems to understand. Study of a Chihuahuan desert ecosystem near Portal, Arizona, USA, began in 1977. At this site, 24 experimental plots were established in 1977 and divided among controls and experimental manipulations. Experimental manipulations over the years include removal of all or some rodent species, all or some ants, seed additions, and various alterations of the annual plant community. While some …


The Taxonomic Designation Of Eriogonum Corymbosum Var. Nilesii (Polygonaceae) Is Supported By Aflp And Cpdna Analyses, M. W. Ellis, J. M. Roper, R. Gainer, J. P. Der, Paul G. Wolf Jan 2009

The Taxonomic Designation Of Eriogonum Corymbosum Var. Nilesii (Polygonaceae) Is Supported By Aflp And Cpdna Analyses, M. W. Ellis, J. M. Roper, R. Gainer, J. P. Der, Paul G. Wolf

Biology Faculty Publications

We examined populations of perennial, shrubby buckwheats in the Eriogonum corymbosum complex and related Eriogonum species in the subgenus Eucycla, to assess genetic affiliations of the recently named E. corymbosum var. nilesii. The known populations of this varietyare all located in Clark County, Nevada, U. S. A. We compared AFLP profiles and chloroplast DNA sequences of plants sampled from populations of E. corymbosum var. nilesii with those of plants representing other E. corymbosum varieties and related Eriogonum species from Colorado,Utah, northern Arizona, and northern New Mexico. We found evidence of genetic cohesion among the Clark County populations as well astheir …


Conservation Of Selection On Matk Following An Ancient Loss Of Its Flanking Intron, A. M. Duffy, S. A. Kelchner, Paul G. Wolf Jan 2009

Conservation Of Selection On Matk Following An Ancient Loss Of Its Flanking Intron, A. M. Duffy, S. A. Kelchner, Paul G. Wolf

Biology Faculty Publications

The chloroplast gene trnK and its associated group II intron appear to be absent in a large and ancient clade that includes nearly 90% of fern species. However, the maturase protein encoded within the intron (matK) is still present and located on the boundary of a large-scale inversion. We surveyed the chloroplast genome sequence of clade-member Adiantum capillus-veneris for evidence of a still present but fragmented trnK intron. Lack of signature structural domains and sequence motifs in the genome indicate loss of the trnK intron through degradation in an ancestor of the clade. In plants, matK preferentially catalyzes splicing of …


Evolutionary Time For Dispersal Limits The Extent But Not The Occupancy Of Species’ Potential Ranges In The Tropical Plant Genus Psychotria (Rubiaceae), John R. Paul, Cynthia Morton, Charlotte M. Taylor, Stephen J. Tonsor Jan 2009

Evolutionary Time For Dispersal Limits The Extent But Not The Occupancy Of Species’ Potential Ranges In The Tropical Plant Genus Psychotria (Rubiaceae), John R. Paul, Cynthia Morton, Charlotte M. Taylor, Stephen J. Tonsor

Biology Faculty Publications

Explaining the diversity in geographic range sizes among species is a central goal of ecological and evolutionary studies. We tested species age as an explanation of range size variation within a group of understory shrubs in the Neotropics (Psychotria subgenus Psychotria, Rubiaceae). We distinguish between range occupancy (filling an occupied area) and range extent (maximum distances dispersed). We used Bayesian relaxed-clock dating of molecular sequence data to estimate the relative age of species, and we used species distribution modeling to predict species' potential ranges. If the range sizes of species are limited by time for dispersal, we hypothesize that older …


Virus-Encoded Homologs Of Cellular Interleukin-10 And Their Control Of Host Immune Function, Barry Slobedman, Peter A. Barry, Juliet V. Spencer, Selmir Avdic, Allison Abendroth Jan 2009

Virus-Encoded Homologs Of Cellular Interleukin-10 And Their Control Of Host Immune Function, Barry Slobedman, Peter A. Barry, Juliet V. Spencer, Selmir Avdic, Allison Abendroth

Biology Faculty Publications

No abstract provided.


Global Chloroplast Phylogeny And Biogeography Of Bracken (Pteridium: Dennstaedtiaceae), J. P. Der, J. A. Thomson, J. K. Stratford, Paul G. Wolf Jan 2009

Global Chloroplast Phylogeny And Biogeography Of Bracken (Pteridium: Dennstaedtiaceae), J. P. Der, J. A. Thomson, J. K. Stratford, Paul G. Wolf

Biology Faculty Publications

Bracken ferns (genus Pteridium) represent an ancient species complex with a natural worldwide distribution. Pteridium has historically been treated as comprising a single species, but recent treatments have recognized several related species. Phenotypic plasticity, geographically structured morphological variation, and geographically biased sampling have all contributed to taxonomic confusion in the genus. We sampled bracken specimens worldwide and used variable regions of the chloroplast genome to investigate phylogeography and reticulate evolution within the genus. Our results distinguish two major clades within Pteridium, a primarily northern hemisphere Laurasian/African clade, which includes all taxa currently assigned to P. aquilinum, and a primarily southern …


Horseshoe Crab Spawning Survey Protocol, Jennifer Mattei Jan 2009

Horseshoe Crab Spawning Survey Protocol, Jennifer Mattei

Biology Faculty Publications

The protocol lists supplies and clothing needed for the survey, as well as which data is to be collected and when and how it should be entered for the census of horseshoe crabs on the Recapture Data Sheet for 2009. Adopted from Cape Cod and Delaware Bay survey protocols.


Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann Dec 2008

Recombination-Based In Vivo Expression Technology Identifies Helicobacter Pylori Genes Important For Host Colonization, Andrea Castillo, Andrew J. Woodruff, Lynn E. Connolly, William E. Sause, Karen M. Ottemann

Biology Faculty Publications

Here we undertook to identify colonization and gastric disease-promoting factors of the human gastric pathogen Helicobacter pylori as genes that were induced in response to the stomach environment. Using recombination-based in vivo expression technology (RIVET), we identified six promoters induced in the host compared to laboratory conditions. Three of these promoters, designated Pivi10, Pivi66, and Pivi77, regulate genes that H. pylori may use to interact with other microbes or the host. Pivi10 likely regulates the mobA, mobB, and mobD genes, which have potential roles in horizontal gene transfer through plasmid mobilization. Pivi66 occurs in the cytotoxin-associated gene pathogenicity island, a …