Biology Commons^™

Scribble Acts In The Drosophila Fat-Hippo Pathway To Regulate Warts Activity, Shilpi Verghese, Indrayani Waghmare, Hailey Kwon, Katelin Hanes, Madhuri Kango-Singh

Biology Faculty Publications

Epithelial cells are the major cell-type for all organs in multicellular organisms. In order to achieve correct organ size, epithelial tissues need mechanisms that limit their proliferation, and protect tissues from damage caused by defective epithelial cells. Recently, the Hippo signaling pathway has emerged as a major mechanism that orchestrates epithelial development. Hippo signaling is required for cells to stop proliferation as in the absence of Hippo signaling tissues continue to proliferate and produce overgrown organs or tumors. Studies in Drosophila have led the way in providing a framework for how Hippo alters the pattern of gene transcription in target …

Gene Expression Patterns Specific To The Regenerating Limb Of The Mexican Axolotl, James R. Monaghan, Antony Athippozhy, Ashley W. Seifert, Sri Putta, Arnold J. Stromberg, Malcolm Maden, David M. Gardiner, Stephen R. Voss

Biology Faculty Publications

Salamander limb regeneration is dependent upon tissue interactions that are local to the amputation site. Communication among limb epidermis, peripheral nerves, and mesenchyme coordinate cell migration, cell proliferation, and tissue patterning to generate a blastema, which will form missing limb structures. An outstanding question is how cross-talk between these tissues gives rise to the regeneration blastema. To identify genes associated with epidermis-nerve-mesenchymal interactions during limb regeneration, we examined histological and transcriptional changes during the first week following injury in the wound epidermis and subjacent cells between three injury types; 1) a flank wound on the side of the animal that …

Soil Nematodes And Their Prokaryotic Prey Along An Elevation Gradient In The Mojave Desert (Death Valley National Park, California, Usa), Amy M. Treonis, Kelsey Sutton, Brendan Kavanaugh, Archana Narla, Timothy Mcllarky, Jasmine Felder, Cecilia O'Leary, Megan Riley, Alyxandr Pikus, Sarah Thomas

Biology Faculty Publications

We characterized soil communities in the Mojave Desert across an elevation gradient. Our goal was to test the hypothesis that as soil quality improved with increasing elevation (due to increased productivity), the diversity of soil prokaryotes and nematodes would also increase. Soil organic matter and soil moisture content increased with elevation as predicted. Soil salinity did not correlate to elevation, but was highest at a mid-gradient, alluvial site. Soil nematode density, community trophic structure, and diversity did not show patterns related to elevation. Similar results were obtained for diversity of bacteria and archaea. Relationships between soil properties, nematode communities, and …

Cartilage On The Move: Cartilage Lineage Tracing During Tadpole Metamorphosis, Ryan R. Kerney, Alison L. Brittain, Brian K. Hall, Daniel R. Buchholz

Biology Faculty Publications

The reorganization of cranial cartilages during tadpole metamorphosis is a set of complex processes. The fates of larval cartilage-forming cells (chondrocytes) and sources of adult chondrocytes are largely unknown. Individual larval cranial cartilages may either degenerate or remodel, while many adult cartilages appear to form de novo during metamorphosis. Determining the extent to which adult chondrocytes/cartilages are derived from larval chondrocytes during metamorphosis requires new techniques in chondrocyte lineage tracing. We have developed two transgenic systems to label cartilage cells throughout the body with fluorescent proteins. One system strongly labels early tadpole cartilages only. The other system inducibly labels forming …

Seed Dimorphism, Nutrients And Salinity Differentially Affect Seed Traits Of The Desert Halophyte Suaeda Aralocaspica Via Multiple Maternal Effects, Lei Wang, Jerry M. Baskin, Carol C. Baskin, J. Hans C. Cornelissen, Ming Dong, Zhenying Huang

Biology Faculty Publications

BACKGROUND: Maternal effects may influence a range of seed traits simultaneously and are likely to be context-dependent. Disentangling the interactions of plant phenotype and growth environment on various seed traits is important for understanding regeneration and establishment of species in natural environments. Here, we used the seed-dimorphic plant Suaeda aralocaspica to test the hypothesis that seed traits are regulated by multiple maternal effects.

RESULTS: Plants grown from brown seeds had a higher brown:black seed ratio than plants from black seeds, and germination percentage of brown seeds was higher than that of black seeds under all conditions tested. However, the coefficient …

Behavioral And Physiological Female Responses To Male Sex Ratio Bias In A Pond-Breeding Amphibian, Kristine L. Grayson, Stephen P. De Lisle, Jerrah E. Jackson, Samuel J. Black, Erica J. Crespi

Biology Faculty Publications

Introduction: The phenomenon of sexual conflict has been well documented, and in populations with biased operational sex ratios the consequences for the rarer sex can be severe. Females are typically a limited resource and males often evolve aggressive mating behaviors, which can improve individual fitness for the male while negatively impacting female condition and fitness. In response, females can adjust their behavior to minimize exposure to aggressive mating tactics or minimize the costs of mating harassment. While male-male competition is common in amphibian mating systems, little is known about the consequences or responses of females. The red-spotted newt (Notophthalmus …

Serotonin And Synaptic Transmission At Invertebrate Neuromuscular Junctions, Wen-Hui Wu, Robin L. Cooper

Biology Faculty Publications

The serotonergic system in vertebrates and invertebrates has been a focus for over 50 years and will likely continue in the future. Recently, genomic analysis and discovery of alternative splicing and differential expression in tissues have increased the knowledge of serotonin (5-HT) receptor types. Comparative studies can provide useful insights to the wide variety of mechanistic actions of 5-HT responsible for behaviors regulated or modified by 5-HT. To determine cellular responses and influences on neural systems as well as the efferent control of behaviors by the motor units, preparations amenable to detailed studies of synapses are beneficial as working models. …

Rapid Range Expansion In The Great Plains Narrow-Mouthed Toad (Gastrophryne Olivacea) And A Revised Taxonomy For North American Microhylids, Jeffrey W. Streicher, Christian L. Cox, Jonathan A. Campbell, Eric N. Smith, Rafael O. De Sá

Biology Faculty Publications

We investigated genetic variation within the Great Plains narrow-mouthed toad, Gastrophryne olivacea, across its geographic range in the United States and Mexico. An analysis of mitochondrial DNA (mtDNA) from 105 frogs revealed remarkably low levels of genetic diversity in individuals inhabiting the central United States and northern Mexico. We found that this widespread matrilineal lineage is divergent (ca. 2% in mtDNA) from haplotypes that originate from the western United States and western coast of Mexico. Using a dataset that included all five species of Gastrophryne and both species of the closely related genus Hypopachus, we investigated the phylogenetic …

High Prevalence Of The Amphibian Chytrid Fungus (Batrachochytrium Dendrobatidis) Across Multiple Taxa And Localities In The Highlands Of Ethiopia, David J. Gower, Thomas M. Doherty-Bone, Roman K. Aberra, Abebe Mengistu, Silvia Schwaller, Michele Menegon, Rafael O. De Sá, Samy A. Saber, Andrew A. Cunningham, Simon P. Loader

Biology Faculty Publications

Surveys of the potentially lethal amphibian chytrid fungus (Batrachochytrium dendrobatidis - Bd) in Africa are patchy, especially in some regions of high species endemicity. We present results of the first Bd surveys of wild amphibians in Ethiopia, for two upland regions on either side of the Rift Valley: the Bale Mountains and the Kaffa region. Surveys were opportunistic so that robust interpretation of the data is limited. Utilizing diagnostic qPCR assays, 51 out of 120 frogs (14 species in 10 genera) tested positive for Bd at altitudes of 1,620–3,225 m, across all genera and species, and all but …

The Development Of Dermatonotus Muelleri (Anura: Microhylidae: Gastrophryninae), Marissa Fabrezi, Silvia Quinzio, Javier Goldberg, Rafael O. De Sá

Biology Faculty Publications

The monophyly of Microhylidae is supported by an overwhelming accumulation of synapomorphic larval features. Despite the distinctiveness of the microhylid tadpole, few studies have focused on larval development. Microhylid larval morphology is usually described and based on standard tables that imply that developmental events at equivalent stages of overall tadpole development are independent from species-specific patterns of developmental timing. Herein, we present additional developmental data based on external morphology and field data on larval growth for the gastrophrynine microhylid Dermatonotus muelleri. We describe internal morphological variation (e.g., skeletal and soft systems) during larval development. The results indicate that the onset …

Endoplasmic Reticulum Involvement In Yeast Cell Death, Nicanor Austriaco

Biology Faculty Publications

Yeast cells undergo programed cell death (PCD) with characteristic markers associated with apoptosis in mammalian cells including chromatin breakage, nuclear fragmentation, reactive oxygen species generation, and metacaspase activation. Though significant research has focused on mitochondrial involvement in this phenomenon, more recent work with both Saccharomyces cerevisiae and Schizosaccharomyces pombe has also implicated the endoplasmic reticulum (ER) in yeast PCD. This minireview provides an overview of ER stress-associated cell death (ER-SAD) in yeast. It begins with a description of ER structure and function in yeast before moving to a discussion of ER-SAD in both mammalian and yeast cells. Three examples of …

The Acute And Chronic Effect Of Low Temperature On Survival, Heart Rate And Neural Function In Crayfish (Procambarus Clarkii) And Prawn (Macrobrachium Rosenbergii) Species, Yoo Sun Chung, Richard M. Cooper, Justin Graff, Robin L. Cooper

Biology Faculty Publications

The effect of acute and chronic cold exposure on heart rate (HR) and neuronal function in crayfish Procambarus clarkii and prawns Macrobrachium rosenbergii was addressed. This is particularly important since prawn farms of this species are used for aquaculture in varied climates world wide. The success of P. clarkii as an invasive species throughout the world may in part be due to their ability to acclimate to cold and warm habitats. A set of experiments was devised to address the physiological abilities of these species in managing rapid changes to cold environments as well as their ability to respond to …

The Remarkable Life Of Sanak, Roly Russell, Nancy J. Huntly, Spencer Wood, Bruce Finney, Dieta Hanson

Biology Faculty Publications

Life on Sanak is remarkable—from the brilliant orange of lichens clinging to life high on wave-beaten and barren rocks to the raspy bark of an introduced arctic fox or a vole's abstract bouquet of drying tundra flowers. In this chapter we will explore a limited selection of the diverse cast of characters that inhabit the Sanak Islands, ranging from the tiny and cryptic to the large and charismatic.

How Sanak Aleut Fit Into The Intertidal Food Web, Jennifer A. Dunne, Spencer Wood, Roly Russell, Nancy Huntly, Matthew Betts, Herbert Maschner

Biology Faculty Publications

Almost everyone learns about the concept of ecological "food chains" in grade school. An example of a marine food chain is shown on the left-hand side of the chart to the left: phytoplankton are eaten by mussels, which are eaten by octopus, which are eaten by sea otters, which are eaten by humans. These feeding interactions can be abstractly represented as five "nodes" connected in a single chain by four links, as shown on the right-hand side of the diagram to the left. The food chain shown is one of the thousands of interlinked food chains that make up the …

The Ecological Interactions Of Sanak, Nancy Huntly, Spencer Wood, Roly Russell

Biology Faculty Publications

Ecology is not only about the interesting biology of organisms, as described for Sanak Island in the last chapter, but also about interactions: interactions between animals (including people), plants, microbes, the habitats that they live in, and the environments that surround them. The ecology of Sanak Island today reflects not only today's conditions, but also shows the imprint of the distant history of interactions of the island, especially, as we will see below, the imprint of the Aleut people that have made this island their home.

Reproductive Characteristics Of A Populus Euphratica Population And Prospects For Its Restoration In China, Dechang Cao, Jingwen Li, Zhenying Huang, Carol C. Baskin, Jerry M. Baskin, Peng Hao, Weilei Zhou, Junqing Li

Biology Faculty Publications

Populus euphratica is a dominant tree in riparian ecosystems in arid areas of northwest China, but it fails to regenerate in these systems. This study evaluates causes for the failure of sexual and asexual regeneration of this species in the wild. P. euphratica disperses as many as 85743 seeds/m² during summer, and the seeds germinate to 92.0% in distilled water and to 60.8% on silt. However, very few seeds (3.6%) can germinate on unflooded soil. The seed-rain season is prolonged by temporal variability in seed dispersal among individuals, which ensures that seedling emergence can occur during favorable conditions (i.e., …

Evolutionary History And Phylodynamics Of Influenza A And B Neuraminidase (Na) Genes Inferred From Large- Scale Sequence Analyses, Jianpeng Xu, C. Todd Davis, Mary C. Christman, Pierre Rivailler, Haizhen Zhong, Ruben O. Donis, Guoqing Lu

Biology Faculty Publications

Background: Influenza neuraminidase (NA) is an important surface glycoprotein and plays a vital role in viral replication and drug development. The NA is found in influenza A and B viruses, with nine subtypes classified in influenza A. The complete knowledge of influenza NA evolutionary history and phylodynamics, although critical for the prevention and control of influenza epidemics and pandemics, remains lacking.

Methodology/Principal findings: Evolutionary and phylogenetic analyses of influenza NA sequences using Maximum Likelihood and Bayesian MCMC methods demonstrated that the divergence of influenza viruses into types A and B occurred earlier than the divergence of influenza A …

Human Breast Milk And Antiretrovirals Dramatically Reduce Oral Hiv-1 Transmission In Blt Humanized Mice, Angela Wahl, Michael D. Swanson, Tomonori Nochi, Rikke Olesen, Paul W. Denton, Morgan Chateau, J. Victor Garcia

Biology Faculty Publications

Currently, over 15% of new HIV infections occur in children. Breastfeeding is a major contributor to HIV infections in infants. This represents a major paradox in the field because in vitro, breast milk has been shown to have a strong inhibitory effect on HIV infectivity. However, this inhibitory effect has never been demonstrated in vivo. Here, we address this important paradox using the first humanized mouse model of oral HIV transmission. We established that reconstitution of the oral cavity and upper gastrointestinal (GI) tract of humanized bone marrow/liver/thymus (BLT) mice with human leukocytes, including the human cell types important for …

Quantitative Acoustic Analysis Of The Vocal Repertoire Of The Golden Rocket Frog (Anomaloglossus Beebei), Beth A. Pettitt, Godfrey R. Bourne, Mark A. Bee

Biology Faculty Publications

This study describes the vocal repertoire of the Guyanan golden rocket frog, Anomaloglossus beebei, a bromeliad specialist with biparental care. Using multivariate analyses of nine call properties, as well as the occurrence of nonlinear phenomena, three signal types were distinguished—advertisement, courtship, and aggressive calls. Although all three call types were composed of a short series of rapidly repeated pulses, advertisement calls were produced at higher amplitudes and had longer pulse durations than both courtship calls and aggressive calls. Courtship calls exhibited lower dominant frequencies than both advertisement and aggressive calls, which had similar dominant frequencies. Aggressive calls had more …

Aquatic Heteroptera Of The Lake Manguao Catchment, Palawan And New Rank Of Rhagovelia Kawakamii Hoberlandti Hungerford & Matsuda 1961, Hendrik Freitag, Herbert Zettel

Biology Faculty Publications

Results of an inventory of the fauna of aquatic and semiaquatic true bugs (Insecta: Hemiptera) of small streams in a lake catchment of northern Palawan are presented. Twenty-one species were recorded. Taxonomic and ecological notes, distribution and collection sites are given for each identified taxon. Rhagovelia hoberlandti Hungerford & Matsuda 1961 is newly ranked as a subspecies of R. kawakamii (Matsumura 1913): Rhagovelia kawakamii hoberlandti Hungerford & Matsuda 1961, stat.n. Cercotmetus asiaticus Amyot & Serville 1843 is recorded for the first time from the Philippines. Endemic and few undescribed taxa are discussed. Additional environmental data of the sampled waters are …

Identifying Context-Specific Gene Profiles Of Social, Reproductive And Mate Preference Behavior In A Fish Species With Female Mate Choice, Mary E. Ramsey, Tara L. Maginnis, Ryan Y. Wong, Chad Brock, Molly E. Cummings

Biology Faculty Publications

Sensory and social inputs interact with underlying gene suites to coordinate social behavior. Here we use a naturally complex system in sexual selection studies, the swordtail, to explore how genes associated with mate preference, receptivity, and social affiliation interact in the female brain under specific social conditions. We focused on 11genes associated with mate preference in this species (neuroserpin, neuroligin-3, NMDA receptor, tPA, stathmin-2, β-1 adrenergic receptor) or with female sociosexual behaviors in other taxa (vasotocin, isotocin, brain aromatase,α-1 adrenergic receptor, tyrosinehydroxylase). We exposed females to four social conditions, including pairings of differing mate choice complexity (large males, large/ small …

Challenging Disciplinary Boundaries In The First Year: A New Introductory Integrated Science Course For Stem Majors, Lisa Gentile, Lester Caudill, Mirela Fetea, April L. Hill, Kathy Hoke, Barry Lawson, Ovidiu Z. Lipan, Michael Kerckhove, Carol A. Parish, Krista J. Stenger, Doug Szajda

Biology Faculty Publications

To help undergraduates make connections among disciplines so they are able to approach, evaluate, and contribute to the solutions of important global problems, our campus has been focused on interdisciplinary research and education opportunities across the science, technology, engineering, and mathematics (STEM) disciplines. This paper describes the mobilization, planning, and implementation of a first-year interdisciplinary course for STEM majors that integrates key concepts found in traditional first-semester biology, chemistry, computer science, mathematics, and physics courses. This team-taught course, Integrated Quantitative Science (IQS), is half of a first-year student’s schedule in both semesters and is composed of a double lecture and …

Fluorescence-Based Reporter For Gauging Cyclic Di-Gmp Levels In Pseudomonas Aeruginosa, Morten T. Rybtke, Bradley R. Borlee, Keiji Murakami, Yasuhiko Irie, Morten Hentzer, Thomas E. Nielsen, Michael Givskov, Matthew R. Parsek, Tim Tolker-Nielsen

Biology Faculty Publications

The increased tolerance toward the host immune system and antibiotics displayed by biofilm-forming Pseudomonas aeruginosa and other bacteria in chronic infections such as cystic fibrosis bronchopneumonia is of major concern. Targeting of biofilm formation is believed to be a key aspect in the development of novel antipathogenic drugs that can augment the effect of classic antibiotics by decreasing antimicrobial tolerance. The second messenger cyclic di-GMP is a positive regulator of biofilm formation, and cyclic di-GMP signaling is now regarded as a potential target for the development of antipathogenic compounds. Here we describe the development of fluorescent monitors that can gauge …

Hybrid Carbon-Based Scaffolds For Applications In Soft Tissue Reconstruction, Jarema S. Czarnecki, Khalid Lafdi, Robert M. Joseph, Panagiotis A. Tsonis

Biology Faculty Publications

Current biomedical scaffolds utilized in surgery to repair soft tissues commonly fail to meet the optimal combination of biomechanical and tissue regenerative properties. Carbon is a scaffold alternative that potentially optimizes the balance between mechanical strength, durability, and function as a cell and biologics delivery vehicle that is necessary to restore tissue function while promoting tissue repair. The goals of this study were to investigate the feasibility of fabricating hybrid fibrous carbon scaffolds modified with biopolymer, polycaprolactone and to analyze their mechanical properties and ability to support cell growth and proliferation. Environmental scanning electron microscopy, micro-computed tomography, and cell adhesion …

The Interacting Effects Of Clumped Seed Dispersal And Distance- And Density-Dependent Mortality On Seedling Recruitment Patterns, Noelle G. Beckman, Claudia Neuhauser, Helene C. Muller-Landau

Biology Faculty Publications

1. Seed dispersal and natural enemies both influence spatial patterns of seedlings, which in turn influence future abiotic and biotic interactions, with consequences for plant populations, distributions and diversity. Clumped seed deposition is common, especially for vertebrate-dispersed seeds, and has the potential to significantly affect interactions with density-responsive enemies, yet has received relatively little attention.
2. We used spatially explicit simulation models to examine how different patterns of seed dispersal and natural enemy attack structure seedling spatial patterns. We simulated clumped seed dispersal by combining a two-dimensional Student’s T dispersal kernel for expected seed rain with a negative binomial distribution for seed …

Fused Traditional And Geometric Morphometrics Demonstrate Pinniped Whisker Diversity, Carly C. Ginter, Thomas J. Dewitt, Frank E. Fish, Christopher D. Marshall

Biology Faculty Publications

Vibrissae (whiskers) are important components of the mammalian tactile sensory system, and primarily function as detectors of vibrotactile information from the environment. Pinnipeds possess the largest vibrissae among mammals and their vibrissal hair shafts demonstrate a diversity of shapes. The vibrissae of most phocid seals exhibit a beaded morphology with repeating sequences of crests and troughs along their length. However, there are few detailed analyses of pinniped vibrissal morphology, and these are limited to a few species. Therefore, we comparatively characterized differences in vibrissal hair shaft morphologies among phocid species with a beaded profile, phocid species with a smooth profile, …

Skin Regeneration In Adult Axolotls: A Blueprint For Scar-Free Healing In Vertebrates, Ashley W. Seifert, James R. Monaghan, S. Randal Voss, Malcolm Maden

Biology Faculty Publications

While considerable progress has been made towards understanding the complex processes and pathways that regulate human wound healing, regenerative medicine has been unable to develop therapies that coax the natural wound environment to heal scar-free. The inability to induce perfect skin regeneration stems partly from our limited understanding of how scar-free healing occurs in a natural setting. Here we have investigated the wound repair process in adult axolotls and demonstrate that they are capable of perfectly repairing full thickness excisional wounds made on the flank. In the context of mammalian wound repair, our findings reveal a substantial reduction in hemostasis, …

Conserved Transcriptional Unit Organization Of The Cag Pathogenicity Island Among Helicobacter Pylori Strains, Linda H. Ta, Lori M. Hansen, William E. Sause, Olga Shiva, Aram Millstein, Karen M. Ottemann, Andrea Castillo, Jay V. Solnick

Biology Faculty Publications

The Helicobacter pylori cag pathogenicity island (cag PAI) encodes a type IV secretion system that is more commonly found in strains isolated from patients with gastroduodenal disease than from those with asymptomatic gastritis. Genome-wide organization of the transcriptional units in H. pylori strain 26695 was recently established using RNA sequence analysis (Sharma et al., 2010). Here we used quantitative reverse-transcription polymerase chain reaction of open reading frames and intergenic regions to identify putative cag PAI operons in H. pylori; these operons were analyzed further by transcript profiling after deletion of selected promoter regions. Additionally, we used a promoter-trap system to …

Electrochemical Characterization Of The Shell Of The Eastern Oyster, Crassostrea Virginica, Yuhchae Yoon, Andrew S. Mount, Karolyn Hansen, Douglas C. Hansen

Biology Faculty Publications

No abstract provided.

Neurodegeneration - A Means To An End, Amit Singh

Biology Faculty Publications

Cell death, a global phenomenon found throughout the animal kingdom, is a mechanism to maintain tissue homeostasis and for adaptation to changes in the environment [1,2]. Millions of cells die in our body daily- they succumb to stress and commit suicide by a mechanism referred to as cell death or apoptosis [2-4]. Under normal conditions cells are continuously replaced by new cells from the stemor progenitor- cells. For example, an optimum balance in shedding of dead cells from the skin and their replenishment by new ones maintain our health and hygiene. In this context, apoptosis is a mechanism to eliminate …