Biology Commons^™

Conservation Of Selection On Matk In Ferns Following An Ancient Loss 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 …

Immunomodulatory Properties Of A Viral Homolog Of Human Interleukin-10 Expressed By Human Cytomegalovirus During The Latent Phase Of Infection, C Jenkins, W Garcia, M J. Godwin, Juliet V. Spencer, J Lewis Stern, Allison Abendroth, Barry Slobedman

Biology Faculty Publications

Human cytomegalovirus (HCMV) establishes a latent infection in hematopoietic cells, from which it can reactivate to cause significant disease in immunocompromised individuals. HCMV expresses a functional homolog of the immunosuppressive cytokine interleukin-10 (termed cmvIL-10), and alternate splicing of the cmvIL-10 transcript results in expression of a latency-associated cmvIL-10 transcript (LAcmvIL-10). To determine whether LAcmvIL-10 encodes immunosuppressive functions, recombinant LAcmvIL-10 protein was generated, and its impact on major histocompatibility complex class II (MHC-II) expression was examined on granulocyte macrophage progenitor cells (GM-Ps) and monocytes. LAcmvIL-10 (and cmvIL-10) downregulated MHC-II on the surfaces of both cell types. This downregulation was associated with …

Estimation Of Submarine Groundwater Discharge From Bulk Ground Electrical Conductivity Measurements, Thomas Stieglitz, John Rapaglia, Henry Bokuniewicz

Biology Faculty Publications

The utility of bulk ground conductivity (BGC) measurements in the estimation of submarine groundwater discharge (SGD) was investigated at four sites covering a range of hydrogeological settings, namely Cockburn Sound (Australia); Shelter Island (USA); Ubatuba Bay (Brazil) and Flic-en-Flac Bay (Mauritius). At each of the sites, BGC was surveyed in the intertidal zone, and seepage meters were used for direct measurements of SGD flow rates. In the presence of detectable salinity gradients in the sediment, a negative correlation between SGD and BGC was recorded. The correlation is site-specific and is dependent on both the type of sediment and the mixing …

Occurrence And Biological Effect Of Exogenous Steroids In The Elkhorn River, Nebraska, Usa, Alan S. Kolok, Daniel D. Snow, Satomi Kohno, Marlo K. Sellin, Louis J. Guillette Jr.

Biology Faculty Publications

Recent studies of surface waters in North America, Japan, and Europe have reported the presence of steroidogenic agents as contaminants. The current study has three objectives: 1) to determine if steroidogenic compounds are present in the Elkhorn River, 2) to determine if sediments collected from the Elkhorn River can act as a source of steroidogenic compounds to aquatic organisms, and 3) to determine if site-specific biological effects are apparent in the hepatic gene expression of fathead minnows. Evidence was obtained using three approaches: 1) deployment of polar organic chemical integrative samplers (POCIS), 2) deployment of caged fathead minnows, and 3) …

Designation Of A Neotype For Leptodactylus Gracilis (Duméril And Bibron, 1840) (Amphibia: Leptodactylidae), Rafael O. De Sá, A. Dubois, A. Ohler

Biology Faculty Publications

The examination of the preserved specimens in the herpetological collection of the Museum National d'Histoire Naturelle, along with a review of the original literature, indicates that no extant specimen can be undoubtedly identified as the holotype of Leptodactylus gracilis (DumCri.l and Bibron, 1840). Furthermore, it revealed that the type locality recently assigned to this taxon is in error.

Regeneration Of Retinotectal Projections After Optic Tectum Removal In Adult Newts, Mitsumasa Okamoto, Hatsuki Ohsawa, Toshinori Hayashi, Katsushi Owaribe, Panagiotis A. Tsonis

Biology Faculty Publications

Purpose: When injured, the adult newt possesses the remarkable capability to regenerate tissues and organs with return of function and physiology. One example is the newt eye, in which regeneration can restore normal vision if the retina or lens has been removed. We wanted to examine how the retinotectal projections regenerate after removal of the brain’s optic tectum and establish this animal as a model for retinal projection as well as a central nervous system regeneration model.

A Non-Circadian Role For Clock-Genes In Sleep Homeostasis: A Strain Comparison, Paul Franken, Ryan Thomason, H. Craig Heller, Bruce F. O'Hara

Biology Faculty Publications

BACKGROUND: We have previously reported that the expression of circadian clock-genes increases in the cerebral cortex after sleep deprivation (SD) and that the sleep rebound following SD is attenuated in mice deficient for one or more clock-genes. We hypothesized that besides generating circadian rhythms, clock-genes also play a role in the homeostatic regulation of sleep. Here we follow the time course of the forebrain changes in the expression of the clock-genes period (per)-1, per2, and of the clock-controlled gene albumin D-binding protein (dbp) during a 6 h SD and subsequent recovery sleep in three inbred strains of mice for which …

Description Of The Tadpole Of Leptodactylus Pustulatus Peters, 1870 (Anura: Leptodactylidae), Rafael O. De Sá, Reuber Brandão, Lorena Dall'ara Guimarães

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus pustulatus Peters, 1870, are described and illustrated for Gosner stage 39. The internal oral anatomy was analyzed with SEM at Gosner stage 36 whereas chondrocranial anatomy is reported for Gosner stage 35. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the melanonotus species group. The labial tooth row formula is 2(2)/3. Observations are presented that suggest that L. pustulatus engages in larval parental care.

Resumo

São descritas a morfologia externa e o disco oral do girino de …

Comparative Functional Analysis Of Aquaporins/Glyceroporins In Mammals And Anurans, Carissa M. Krane, David L. Goldstein

Biology Faculty Publications

Maintenance of fluid homeostasis is critical to establishing and maintaining normal physiology. The landmark discovery of membrane water channels (aquaporins; AQPs) ushered in a new area in osmoregulatory biology that has drawn from and contributed to diverse branches of biology, from molecular biology and genomics to systems biology and evolution, and from microbial and plant biology to animal and translational physiology. As a result, the study of AQPs provides a unique and integrated backdrop for exploring the relationships between genes and genome systems, the regulation of gene expression, and the physiologic consequences of genetic variation. The wide species distribution of …

Identification And Characterization Of A Carlavirus Causing Veinal Necrosis Of Coleus, Dimitre S. Mollov, Maya C. Hayslett, Kari A. Eichstaedt, Noelle G. Beckman, Margery L. Daughtrey, Ben E. Lockhart

Biology Faculty Publications

A filamentous virus identified in coleus (Coleus x hybrida) in Minnesota and New York was found to cause veinal necrosis in coleus, although this symptom was observed only under certain conditions. The virus was transmitted readily by mechanical inoculation to coleus and Nicotiana spp. and was not transmitted by Myzus persicae. The particles of the coleus virus had a modal length of 640 nm and a single capsid protein with an estimated molecular mass of 34 kDa. The amino acid sequence of the coat protein region of the coleus virus genome had significant similarities only to the …

Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

Natural history researchers are increasingly using digital cameras and computer software to measure their study animals. Adult Red-spotted Newts (Notophthalmus viridescens viridescens) are known to display a range of skin colors, from brown to green, but it has not been possible to quantify this variation until the advent of image analysis technology. We used an image analysis approach to compare skin color between sexes, across a range of sizes, and between aquatic and post-breeding (emigrating to the terrestrial habitat) stage adult newts. From 232 individuals (53% male, 47% female) we documented a wide but subtle range of skin …

The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá

Biology Faculty Publications

The genus Eupsophus is characterized by endotrophic larvae that inhabit water-filled cavities. The larvae feed from large yolk reserves during metamorphosis. The external morphology has been described for four of the ten known species and data on larval chondrocranial morphology are available only for one. We describe the extema1 morphology, oral disc and chondrocranial anatomy of the larvae of Eupsophus queulensis. The characteristics of E. queulensis tadpoles are compared with those of other Eupsophus larvae.

Differential Effects Of Hunting On Pre-Dispersal Seed Predation And Primary And Secondary Seed Removal Of Two Neotropical Tree Species, Noelle G. Beckman, Helene C. Muller-Landau

Biology Faculty Publications

Many of the mammals undergoing drastic declines in tropical forests worldwide are important seed dispersers and seed predators, and thus changes in mammal communities due to hunting will affect plant recruitment. It has been hypothesized that larger-seeded species will suffer greater reductions in seed removal and thus greater increases in predispersal seed predation than smaller-seeded species. We compared primary and secondary seed removal and predispersal seed predation of two tree species between hunted and nonhunted sites in Central Panama. Seeds of Oenocarpus mapora (Arecaceae) are 16-times greater in size than those of Cordia bicolor (Boraginaceae). We quantified primary seed removal …

The Plight Of Large Animals In Tropical Forests And The Consequences For Plant Regeneration, S. Joseph Wright, Kathryn E. Stoner, Noelle Beckman, Richard T. Corlett, Rodolfo Dirzo, Helene C. Muller-Landau, Gabriela Nuñez-Iturri, Carlos A. Peres, Benjamin C. Wang

Biology Faculty Publications

We introduce a special section that addresses the bushmeat or wild meat crisis, its direct impact on game species, and its indirect impact on plants in tropical forests.

Bass Strike Like Lightning, Steve Huskey

Biology Faculty Publications

No abstract provided.

First Slaty-Backed Gull For Minnesota, Philip C. Chu

Biology Faculty Publications

No abstract provided.

The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus notoaktites Heyer, 1978, are described and illustrated for Gosner’s stage 33. The internal oral anatomy was analyzed under SEM at Gosner’s stage 36 whereas chondrocranial anatomy is reported for Gosner’ stage 38. The morphology of this tadpole is compared with those available for other species of the L. mystaceus complex. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the fuscus species group. The labial tooth row formula is 2(2)/3.

Intrarectal Transmission, Systemic Infection, And Cd4+ T Cell Depletion In Humanized Mice Infected With Hiv-1, Zhifeng Sun, Paul W. Denton, Jacob D. Estes, Florence A. Othieno, Bangdong L. Wei, Anja K. Wege, Michael W. Melkus, Angela Padgett-Thomas, Mary Zupancic, Ashley T. Haase, J. Victor Garcia

Biology Faculty Publications

Intrarectal infection between men who have sex with men represents a predominant form of human immunodefi ciency virus (HIV) transmission in developed countries. Currently there are no adequate small animal models that recapitulate intrarectal HIV transmission. Here we demonstrate that human lymphocytes generated in situ from hematopoietic stem cells reconstitute the gastrointestinal tract of humanized mice with human CD4+ T cells rendering them susceptible to intrarectal HIV transmission. HIV infection after a single intrarectal inoculation results in systemic infection with depletion of CD4+ T cells in gut-associated lymphoid tissue and other pathologic sequela that closely mimics those observed in HIV …

Ecological And Genetic Evidence That Low-Order Streams Inhibit Dispersal By Red-Backed Salamanders (Plethodon Cinereus), D. M. Marsh, R. B. Page, T. J. Hanlon, H. Bareke, R. Corritone, N. Jetter, N. G. Beckman, K. Gardner, D. E. Seifert, P. R. Cabe

Biology Faculty Publications

While many studies have examined the barrier effects of large rivers on animal dispersal and gene flow, few studies have considered the barrier effects of small streams. We used displacement experiments and analyses of genetic population structure to examine the effects of first-order and second-order streams on the dispersal of terrestrial red-backed salamanders, Plethodon cinereus (Green, 1818). We marked red-backed salamanders from near the edges of one first-order stream and one second-order stream, and experimentally displaced them either across the stream or an equal distance farther into the forest. A comparison of return rates indicated that both streams were partial …

Delimitation Of Major Lineages Within Cuscuta Subgenus Grammica (Convolvulaceae) Using Plastid And Nuclear Dna Sequences, Saša Stefanović, Maria Kuzmina, Mihai Costea

Biology Faculty Publications

Subgenus Grammica, the largest and most diverse group in the parasitic genus Cuscuta, includes ~130 species distributed primarily throughout the New World, with Mexico as its center of diversity. To circumscribe the subgenus ans assess the relationships among its major lineages, we conducted the first phylogenetic study of Grammica using plastid trnL F and nrITS sequences from a wide taxonomic sampling covering its morphological, physiological, and geographical diversiity. With the exception of of one species belonging elsewhere, the subgenus was found to be monophyletic. The results further indicate the presence of 15 well supported major clades within Grammica …

Selective Activation Of Estrogen Receptor-Β Transcriptional Pathways By An Herbal Extract, Aleksandra Cvoro, Sreenivasan Paruthiyil, Jeremy O. Jones, Christina Tzagarakis-Foster, Nicola J. Clegg, Deirdre Tatomer, Roanna T. Medina, Mary Tagliaferri, Fred Schaufele, Thomas S. Scanlan, Marc I. Diamond, Isaac Cohen, Dale C. Leitman

Biology Faculty Publications

Novel estrogenic therapies are needed that ameliorate menopausal symptoms and have the bone-sparing effects of endogenous estrogens but do not promote breast or uterine cancer. Recent evidence suggests that selective activation of the estrogen receptor (ER)-beta subtype inhibits breast cancer cell proliferation. To establish whether ERbeta-selective ligands represent a viable approach to improve hormone therapy, we investigated whether the estrogenic activities present in an herbal extract, MF101, used to treat hot flashes, are ERbeta selective. MF101 promoted ERbeta, but not ERalpha, activation of an estrogen response element upstream of the luciferase reporter gene. MF101 also selectively regulates transcription of endogenous …

Loathsome Beasts: Images Of Reptiles And Amphibians In Art And Science, Kay Etheridge

Biology Faculty Publications

The mythology and symbolism historically associated with reptiles and amphibians is unequaled by that of any other taxonomic group of animals. Even today, these creatures serve as icons - often indicating magic or evil - in a variety of media. Reptiles and amphibians also differ from other vertebrates (i.e. fish, mammals and birds) in that most have never been valued in Europe as food or for sport. Aside from some limited medicinal uses and the medical concerns related to venomous species, there was little utilitarian value in studying the natural history of reptiles and amphibians. Because of this history and …

First Breeding Of The Snowy Plover In Minnesota, Philip C. Chu

Biology Faculty Publications

No abstract provided.

Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe

Biology Faculty Publications

Funnel traps of various designs have been used to capture adults and larvae of aquatic amphibians (e.g., Buech and Egeland 2002; Richter 1995). Most studies use unbaited funnel traps to capture amphibians while others have used shrimp or salmon eggs (Adams et al. 1997). Light traps and light sticks are commonly used in studies of fish, particularly larvae (Doherty 1987; Marchetti et al. 2004), but have not been widely used to capture amphibians. Glow sticks have been mentioned briefly in the literature as a means to increase capture rates of aquatic amphibians (Smith and Rettig 1996), but no studies have …

A Practical Approach To Phylogenomics: The Phylogeny Of Ray-Finned Fish (Actinopterygii) As A Case Study, Chenhong Li, Guillermo Orti, Gong Zhang, Guoqing Lu

Biology Faculty Publications

Background: Molecular systematics occupies one of the central stages in biology in the genomic era, ushered in by unprecedented progress in DNA technology. The inference of organismal phylogeny is now based on many independent genetic loci, a widely accepted approach to assemble the tree of life. Surprisingly, this approach is hindered by lack of appropriate nuclear gene markers for many taxonomic groups especially at high taxonomic level, partially due to the lack of tools for efficiently developing new phylogenetic makers. We report here a genome-comparison strategy to identifying nuclear gene markers for phylogenetic inference and apply it to the …

Electrical And Behavioral Courtship Displays In The Mormyrid Fish Brienomyrus Brachyistius, Ryan Y. Wong, Carl D. Hopkins

Biology Faculty Publications

Mormyrid electric fish rely on the waveform of their electric organ discharges (EODs) for communicating species, sex, and social status, while they use the sequences of pulse intervals (SPIs) for communicating rapidly changing behavioral states and motivation. Little is known of electric signaling during courtship behavior because of two major difficulties: (1) the fish are not easily bred in captivity and (2) there is no reliable means of separating electric signals from several individuals in natural communication settings. Through simulating artificial rain conditions, we have successfully induced courtship and succeeded in breeding a mormyrid electric fish (Brienomyrus brachyistius) in the …

The Diatom Flora Of Phosphorus-Enriched And Unenriched Sites In An Everglades Marsh, Jennifer E. Slate, R Jan Stevenson

Biology Faculty Publications

Diatoms are used as environmental indicators in the Florida Everglades, a large subtropical wetland highly impacted by phosphorus pollution. However, the taxonomy of the diatom flora, a mix of temperate and tropical diatoms, is understudied. Therefore, we analyzed the taxonomy of 71 diatom taxa collected in Water Conservation Area 2A (WCA-2A). Diatoms were analyzed from sediment cores and from floating algal mats collected in phosphorus-enriched northern WCA-2A and in relatively unenriched southern WCA-2A. In addition, diatoms were analyzed from experimental mesocosms in southern WCA- 2A dosed with 0-126 µgL^-1 P-PO₄. Total phosphorus optima were calculated for dominant …

Relationships Between Body Size And Abundance In Ecology, Ethan P. White, S.K. Morgan Ernest, A. J. Kerkoff, B. J. Enquist

Biology Faculty Publications

Body size is perhaps the most fundamental property of an organism and is related to many biological traits, including abundance. The relationship between abundance and body size has received much attention, both to quantify the form of the relationship and to understand the processes that generate it. However, progress is impeded by the underappreciated fact that there are four distinct, but inter-related, relationships between size and abundance that are often confused in the literature. Here, we review and distinguish between these four patterns, and discuss the linkages between them. We argue that a synthetic understanding of size and abundance relationships …

Ecological Correlates Of Geographic Range Occupancy In North American Birds, A. H. Hurlbert, Ethan P. White

Biology Faculty Publications

The degree to which a species is predictably encountered within its range varies 36 tremendously across species. Understanding why some species occur less frequently within their 37 range than others has important consequences for conservation and for range map based analyses 38 of ecological patterns. We examined whether patterns in geographical range occupancy can be 39 explained by species level traits.

Challenges In The Application Of Geometric Constraint Models, C. R. Mcclain, Ethan P. White, A. H. Hurlbert

Biology Faculty Publications

Discerning the processes influencing geographic patterns of species richness remains one of the central goals of modern ecology. Traditional approaches to exploring these patterns have focused on environmental and ecological correlates of observed species richness. Recently, some have suggested these approaches suffered from the lack of an appropriate null model that accounts for species’ ranges being constrained to occur within a bounded domain. Proponents of these null geometric constraint models (GCMs), and the mid-domain effect these models produce, argue their utility in identifying meaningful gradients in species richness. This idea has generated substantial debate. Here we discuss what we believe …