Carole Browne, with Mary Lou Voytko, WFUHS Neurobiology & Anatomy
Effects of Estrogen on Cholinergic Indices in Surgically Menopausal Monkeys
Awarded $15,000 for the period 5/6/05 to 5/15/06
Source: WFU Cross-Campus Collaborative Research Fund

Ovarian hormone deficiency resulting from natural or surgical menopause can change cognitive functioning, especially memory and attention. Several studies of postmenopausal women indicated that estrogen replacement therapy (ERT) improved memory and attention, but its neurobiological mechanisms have not been well defined. It may affect the basal forebrain cholinergic system (BFCS) neurons located in the nucleus basalis of Meynert that project to cortical regions and in the medial septal/diagonal band nuclei (MS/DB) that project to hippocampus. This project investigates the effects of chronic ERT on the cholinergic system of surgically menopausal young adult and middle-aged monkeys. The data will be used as pilot data for an RO1 application to the National Institute on Aging for a project to determine the extent to which age influences the effects of ERT on cholinergic indices in monkey models of menopause and the degree to which these effects correlate with behavioral indices.

Robert Browne
Population Genetics Structure and Species Composition of Ground Beetle Communities in the Boreal Forest ‘Sky Island’ in the Southern Appalachian Mountains
Awarded $9,600 for the period 5/1/05 to 4/30/06
Source: WFU Science Research Fund

Flightless ground beetles will be collected from 12 spruce-fir forests in the southeastern United States to test whether species presence correlates with spruce-fir island size, altitude, presence of conifer forest, level of past fire disturbance, and level of logging intensity. Multiple sampling techniques will allow more complete species inventories, while determining seasonal and annual variations in the communities’ composition. Each technique’s efficiency can also be compared and assessed . Molecular techniques will be used to quantify genetic distances among select taxon units and to analyze population genetic structure.

William E. Conner

• Student Ambassador to the National Collegiate Innovators Alliance
  Awarded $6,000 for the period 9/1/10 to 6/30/11
  Source: National Collegiate Inventors & Innovators Alliance (NCIIA)

Mr. William Oelsner will serve as the university’s NCIIA Student Ambassador, creating networks and events to encourage campus entrepreneurs to become involved in NCIIA programs and activities and to support their development of socially beneficial innovations.

• Acoustic Aposematism, Mimicry, and Sonar Jamming in the Bat-Moth Arms Race
  Awarded $120,000 for the period 5/18/10 to 5/31/11
  Source: NSF

The interactions of insectivorous bats and their prey can be seen as an evolutionary arms race. First, bats evolved sophisticated, high-frequency sonar that lets them echolocate and track flying insects. Many nocturnal insects, including moths, then evolved sonar-detecting devices that alert them to the echolocation cries of approaching bats. Tiger moths (Lepidoptera: Arctiidae) can even answer bats with a series of intense ultrasonic clicks produced by paired thoracic structures called tymbals. Dr. Conner’s research supports 3 functions for these clicks: warning, mimicry, and sonar jamming.

After over 8 years of laboratory experimentation, new field studies in North Carolina and southeastern Arizona will evaluate the efficacy of acoustic aposematism, mimicry, and sonar jamming in nature. First, high-speed infrared thermal imaging, 3D image analysis, and voice-recognition software will be used to identify both participants. Second, molecular probes based on species-specific nucleotide sequences will be used to quantify each moth species in the guano pellets of naturally foraging bats. Results will be compared to field counts, and underrepresented moth species will be considered protected against echolocating bats. The project will educate graduate students, undergraduates, and grade-school children in partnership with SciWorks, a science center and environmental park visited by over 30,000 K-12 students per year.

• see also Michelle DaCosta

• Sound Strategies: Acoustic Mimicry and Jamming in the Bat-Moth Arms Race
  Awarded $185,223 for the period 7/01/06 to 6/30/09
  Source: NSF

Insectivorous bats with ultrasonic sonar exert enormous selective pressure on nocturnal insects. In response, insects have evolved the ability to hear bat cries, to evade their hunting maneuvers, and tiger moths (Arctiidae) utter an ultrasonic reply. Using a novel learning approach, we have shown that the bats only respond to the sounds of arctiids when they are paired with defensive chemistry. The sounds are a warning to the bats that the moth is unpalatable – an aposematic signal.

Although the sounds of arctiids have so far been shown to have this single function, they are extremely diverse in structure. Using free-flying naïve red bats and tethered tiger moths, this project explores the other evolutionary forces may contribute to this diversity. It asks whether some palatable tiger moth species mimic the sounds of unpalatable species to gain an advantage and whether some species have modified their warning signals in a way that allows them to “jam” the echolocation sonar system of the bat and mask their presence.

A team of graduate and undergraduate students will study these questions in the Wake Forest Bat Facility directed by Professor Conner. The results will be shared with children through an educational website devoted to bats and moths. Wake Forest undergraduates will also teach in the summer ecology camp at Archbold Biological Station in Lake Placid, FL.

James F. Curran

• AREA: Translational roles of the ribosomal E site
  Awarded $204,951 for the period 7/1/09 to 6/30/12
  Source: National Institutes of Health (NIH)

The accuracy of ribosomal protein synthesis is critical to the health of all cells. Evidence clearly shows that ribosomes contain an exit, or E site, for de-acylated tRNA and that tRNA passes through it after completing its translational role. Theory suggests that this site is important for maintaining the translational reading frame and ensuring accurate aminoacyl-tRNA selection at the ribosomal A site. Dr. Curran’s laboratory has already provided strong evidence that E site tRNA helps to hold the reading frame. This project will determine whether E site tRNA affects aminoacyl-tRNA selection at the A site, while contributing to the biomedical research training of promising graduate and undergraduate students.

• Analysis of protein synthesis in E. coli by high-throughput pyrosequencing
  Awarded $10,000, Spring 2007
  Source: WFU Science Research Fund

Protein synthesis is a critical step in gene expression. The basic mechanics of the translational process are understood but almost nothing is known about how ribosomes process messages. This project aims to provide a snapshot of the message sequences that are translated during standard growth conditions. A new method, pyrosequencing, can simultaneously determine the sequences for several hundred thousand short RNAs. Ribosomes will be isolated; any mRNA not protected by them will be digested; and the protected sequences pyrosequenced. Their pattern will tell us the relative frequency at which all messages are translated, and the distribution of ribosomes will tell us a great deal about how they move over messages. The project brings a powerful new technology to the Wake Forest biomedical research community.

• AREA: Does the Ribosomal E Site Help Hold the Reading Frame?
  Awarded $209,205 for the period 7/1/06 to 6/30/09
  Source: NIH

Maintaining the translational reading frame is a fundament feature of protein synthesis. Ribosomes contain an exit, or E, site for deacylated tRNA, which passes through after completing its translational role. Except for transient interactions with the exiting tRNA, however, no clear function has been identified for the E site. Recent evidence suggests the hypothesis that deacylated tRNA in the ribosomal E site helps to prevent frameshifting. This project will test it by determining whether message nucleotides and tRNA in the E site are associated with increased or decreased frameshifting at the RF2 programmed frameshift site. Preliminary work shows that the E site triplet is important, although the mechanism is not yet clear. The project will also determine whether the E site holds tRNA until an aminoacl-tRNA is selected at the A site. If so, then the E site tRNA might have an important functional role during translation of the A site. If not, then it may have a transient role, possibly in message translocation. From 3-6 undergraduate students and 2-3 MS-level graduate students will perform much of the work.

• The Roles of the Ribosomal E Site in Translation
  Awarded $8,000 for the period 6/1/05 to 5/31/06
  Source: WFU Science Research Fund

  Recent work suggests that the ribosomal E (exit) site may play critical roles in maintaining the translational reading frame. Specific tests of this hypothesis will use standard molecular cloning techniques to enable the assay of effects on gene expression in living E. coli. .

• with Rebecca Alexander, Chemistry, and WSSU
  Research Infrastructure in Minority Institution Grant (RIMI)
  Awarded $15,595 for the period 9/30/06 to 9/29/07
  Source: NIH/Winston-Salem State University

Bacteria significantly overproduce a protein called CsdA when the environmental temperature drops. CsdA may work to unwind RNA, because at low temperatures, a possible increase in RNA secondary structure would inhibit mRNA translation at the ribosome. In collaboration with PI Pamela Jones, a microbiologist at Winston-Salem State University, Dr. Curran will assay CsdA mutations in vivo, looking for translation defects and growth phenotypes, while Dr. Alexander will purify CsdA mutants and assay the effect on RNA binding and unwinding in vitro, to learn what protein motifs in CsdA contribute to the observed functions.

Michelle DaCosta, with William Conner
Defensive Signaling Behaviors and the Influence of Predator Learning on Communication Modalities in the Chetheisa Species in the Galapagos Islands
Awarded $5,000 for the period 9/1/09 to 8/31/10
Source: NSF

Aposematism is a term to describe adaptations — colors, sounds, odors, or other perceivable characteristics — that warn predators off, as opposed to crypsis, which means avoiding detection. In Lepidoptera, unpalatable species are often aposematic, while undefended species tend to be cryptic. Birds, their major diurnal predators, can detect signals in both the visual and ultraviolet regions of the spectrum and learn to avoid aposematic prey. Lizards also detect visual signals but rely more on movement than aposematism. How predator pressure, evolutionary history, and geography interact to favor aposematism or crypsis remains unclear. This project focuses on the defensive signaling of four species of tigermoth, one of which,distributed throughout the Americas, including the Galapagos Islands, is aposematic; the remaining three, endemic to the Galapagos islands, are cryptic, the only cryptic species in the genus, even though they feed on toxic plants. Objectives include 1) quantifying aposematic vs. cryptic behaviors; 2) determining if both birds and lizards learn to avoid aposematic prey; and 3) using molecular data to reconstruct the evolutionary history of these species.

Susan Fahrbach

• Role of Nuclear Receptors in Neural Plasticity
  Awarded $140,000 for the period 1/24/11 to 3/31/12
  Source: NSF

A critical feature of social organization in honey bee colonies is age-based division of labor among workers. For the first 2-3 weeks of adult life, they tend the queen, rear larval brood, and maintain hive architecture, while in their final 1-3 weeks, they forage outside the hive. Foragers show predictable changes in brain volume, including growth of the dendrites of the intrinsic neurons (Kenyon cells) of the mushroom bodies, the primary arthropod brain structure associated with learning and memory. This project aims to clarify why dendritic growth is more prominent during some behavioral development stages than others and why receptors for developmental hormones are expressed so abundantly in the adult insect brain. Long-term, it will enable researchers to control mushroom body growth in vivo as an essential tool for addressing its adaptive function. Broader impacts include support of a doctoral student and a new Bioinformatics for Beginners seminar course, which the co-PIs will teach at Wake Forest University each year of the award. Free access to its teaching materials will be provided via a bilingual (English/Spanish) website.

• Young Investigators Symposium at the Steroid Workshop
  Awarded $13,050 for the period 4/1/08 to 3/31/09
  Source: NSF

Funding supports the Young Investigator Symposium of the annual Workshop on Steroid Hormones and Brain Function for two years. Five competitively chosen senior graduate students and postdoctoral fellows present and discuss their research findings. Over the past 13 years, it has consistently attracted outstanding applicants, including women and minorities. The workshop, now in its 17th year, provides an informal setting in which scientists using a wide array of strategies and technologies can discuss their current research in neuro-endocrinology. Its intentionally limited size encourages collaborative and cross-disciplinary interaction among junior and senior investigators. Past sessions have dealt with topics ranging from fetal development to aging, novel concepts of steroid receptor activation, the role of steroid receptor co-activators, and the role of orphan receptors in brain and behavior. The neural basis of gender differences in behavioral responses across vertebrate classes is an emphasis, but contributions from invertebrate model systems are welcome, so participants can place their work in the broadest possible phylogenetic context. Information related to the workshop and the Young Investigator Symposium is broadly disseminated at www.steroidworkshop.org/.

• FIBR: BeeSpace – An interactive Environment for Analyzing Nature and Nurture in Societal Roles
  Awarded $114,183 for the period 9/1/04 to 8/31/08
  Source: NSF/University of Illinois

The project focuses on the honey bee to elucidate the relationship between genes and animal social life on an unprecedented whole-genome scale. Its interactive environment integrates molecular description with information from ecology, evolution, behavioral science, and physiology. All the roles of a worker honey bee within her society will be functionally analyzed by combining microarray analysis, large-scale brain in situ hybridization, and a novel approach to informatics that links all sources from current genomic databases to the existing scientific and natural history literatures on honey bees. The resulting database will localize the expression of many bee genes to precise regions of the brain for all major social roles. A novel software environment, called BeeSpace, enables users to navigate interactively across sources for hypothesis development and testing. The prototype will be tested in 15 laboratories studying honey bees and related organisms and provide research experiences at the graduate, undergraduate, high school, and middle school levels, with training and minority outreach.

• Muscarinic regulation of plasticity in the brain
  Awarded $68,150 for the period 3/31/09 to 3/31/10
  Source: NIH/University of Illinois
  

This project examines how experience translates into changes in brain structure that enhance adult performance. It is based on the surprising demonstration that treating foraging honey bees with a muscarinic agonist, pilocarpine, induces growth of the mushroom bodies, the insect brain center for learning and memory, resulting in a brain plasticity identical to that produced by a week of foraging. The honey bee provides a superb model system for these studies because appropriate tools, such as the sequenced genome, are available and the effects of experience on brain structure are better understood than in any other insect. Nervous system function at the molecular level is highly conserved across the animal kingdom; thus, experiments that can be efficiently performed using the simpler insect system are likely to reveal how learning changes the brain in all animals, including humans. Such understanding is the first step in developing therapies to improve human learning after brain damage or with the decline that accompanies aging.

• Role of Orphan Nuclear Hormone Receptors in the Adult Honey Bee Brain
  Awarded $103,688 for the period 9/1/05 to 8/31/06
  Source: NSF

The honey bee brain serves as a model for neuronal plasticity coupled with behavioral development; in other words, how the brain changes with age. In honey bee colonies, a critical feature of social organization is age-based division of labor among workers. They tend the queen, rear larval brood, and maintain the physical structure of the hive for the first 2 to 3 weeks of adult life then switch to foraging outside the hive for their final 1 to 3 weeks, and studies show predictable changes in foragers’ brain structure, including the expansion of the neuropil of the mushroom bodies, the primary arthropod brain region associated with learning and memory with some similarities to the vertebrate hippocampus. More specifically, Golgi analyses have shown that the brain volume changes associated with foraging reflect growth of Kenyon cell dendrites. This project seeks to identify the mechanisms that permit Kenyon cells in the adult bee brain to grow in response to changes in experience. Members of the nuclear hormone receptor (NHR) superfamily are candidate regulators of neuronal structure. Analysis of a Bee Brain EST Database revealed that 6 homologs of Drosophilia melanogaster NHRs are expressed in the adult bee brain. Quantitative real-time PCR, in situ hybridization, and manipulation of gene expression in primary cultures of Kenyon cells will be used to test two hypotheses:
1. Neuronal populations showing dendritic growth during behavioral development in the adult honey bee will be characterized by the expression of NHRs; and
2. Process outgrowth with require signaling though NHR-activated pathways.

These studies will contribute new knowledge of the mechanisms of structural plasticity in the adult nervous system and the insect members of the NHR superfamily. Participating graduate and undergraduate students will learn to use several new bioinformatics tools to exploit the Honey Bee Genome Project.

• Functional Genomics of Chronobiological Plasticity in the Honey Bee
  Awarded $9,775 for the period 9/1/07 to 8/31/08
  Source: United States-Israel Binational Science Foundation (BSF)

The project integrates a genomic approach to study complex behavior: the molecular biology of the honey bee circadian clock and socially mediated chronobiological plasticity. Bioinformatic and phylogenetic analyses will identify bee homologs for all pivotal clock genes; and immunocytochemistry and in situ hybridization will be used to determine the spatial expression of clock genes under varying light conditions. Hypotheses include:
1) all clock genes are expressed in pacemaker cells;
2) expression of most or all of these genes will oscillate with circadian rhythm;
3) their phase will shift after alterations in photoperiod; and
4) oscillations in arrhythmic nurses will be smaller than in rhythmic foragers.

Preliminary results suggest that in some ways, the honey bee clock more resembles that of the mouse than the fly. Taking into account the structural and functional conservation of the circadian clock, findings may provide new insights into circadian plasticity in general.

Erik Johnson

• Roles of AMP-activated kinase in metabolic homeostasis in Drosophila
  Awarded $330,278 for the period 8/15/09 to 7/31/11
  Source: NSF

Changes in food availability significantly challenge organisms to maintain constant energy stores. The AMP-activated kinase is a highly conserved molecule that becomes active during energy shortages. This project takes advantage of the unique molecular and genetic tools available for the fruit fly, Drosophila melanogaster, to investigate how the AMP-activated kinase regulates behavioral and physiological changes under starvation conditions. It will contribute new information on the cellular signals in defined neural and peripheral tissues with applications from pest management to novel therapeutics, while extending research opportunities to undergraduate and graduate students and enhancing faculty professional development at a primarily undergraduate institution, Francis Marion University (FMU).

• Genetic Manipulation of a Neuroendocrine Circuit in Drosophila
  Awarded $10,000 for the period 12/1/05 to 11/30/06
  Source: WFU Science Research Fund

In Drosophila, at least four different diuretic peptide hormones control osmotic balance. Evaluation of their expression patterns and dedicated receptors has revealed a neuroendocrine circuit within the brain. Both the molecular components and the anatomical organization of Drosophila diuretic hormone signaling are similar to specific mammalian neuropeptide signaling pathways. We will test hypotheses that activating one hormone receptor affects the release of its co-expressed hormone by either facilitating, inhibiting, or modulating secretion profiles.

Kathleen A. Kron

• Collaborative Research: Phylogenetic, biogeographic, and monographic studies in the wintergreen group
  Awarded $122,720 for the period 8/1/09 to 8/32/10
  Source: NSF

Its amphi-Pacific distribution and diverse fruit and anther morphology make the wintergreen group (Gaultherieae) particularly interesting within the blueberry and rhododendron family (Ericaceae). This collaborative project will study its evolution using eight nucleotide sequences obtained from the nuclear and chloroplast genomes of approximately 250 species. Phylogenetic analyses will test biogeography hypotheses. Monographic work will be performed on selected strongly supported clades that can also be diagnosed using morphological features. In addition to publication in peer-reviewed journals, data, images, measurements, and results will be made available electronically via the Plone system and Kron’s website, www.ericaceae.org. The study will train three graduate students.

• Ericaceae in the Central Andes: Bolivia and Adjacent Peru
  Awarded: $7,000 for the period 7/1/05 to 1/31/08
  Source: NSF

This cooperative research program focuses on a flora of the Ericaceae in Bolivia and southern Peru, two poorly collected areas that are being rapidly deforested. The Principal Investigator, James Luteyn, New York Botanical Garden, and members of several South American herbaria are collecting ericaceous plants for research purposes, writing identification keys, and providing the basis for future monographs and revisionary work. Dr. Kron will use DNA sequence data to place the discovered taxa within the phylogenetic framework of the remaining neotropical blueberries and wintergreens. Results will contribute to a better understanding of the evolution of South American Ericaceae, a more robust phylogeny for the “Andean Clade”, and help to identify artificially delineated taxa from natural (monophyletic) ones. The specimens collected by Luteyn and collaborators will be housed in herbaria in South America and the New York Botanical Garden, and results disseminated electronically and via scholarly journals and identification keys. In addition, Colombian students will receive training in modern taxonomic techniques and standard field practice.

• Evolutionary Relationships in the Rhubarb Family (Polygonaceae), using Data from NuclearGgenes LEAFY and AGAMOUS
  Awarded $10,000 for the period 5/1/05 to 4/30/06
  Source: WFU Science Research Fund

  The rhubarb family is a group of flowering plants that contains many species of economic or agricultural importance. The flowers of most of the members have a unique tepal arrangement. This project will study the evolution of the perianth arrangement and other features, including fruit diversification, dispersal mechanisms, reproductive biology, and ocrea. It expands my consistently funded research program from the Ericaceae (blueberries & rhododendrons) to include the rhubarb family. Data from two neglected nuclear genes will be used to study evolution in the Polygonaceae.

Raymond F. Kuhn

• Diagnostic Assay and Nutraceutical for Enteric Septicemia of Catfish (ESC)
  Awarded $75,000 for the period 8/1/07 to 1/31/09
  Source: North Carolina Biotechnology Center

The aquaculture industry is burgeoning in response to decreased wild fish populations and increasing demand for sustainable sources of protein. The predominant species farmed in the United States, 95% in the southeast, is the channel catfish. While total US catfish sales in 2005 were approximately $482 million and estimated to grow 8% per year, the global aquaculture market totals about $60.9 billion. US fish farmers operate under thin profit margins threatened by imports and infectious diseases. Catfish are durable but susceptible to bacterial infections that contribute to losses as high as 30%. In most cases, they are treated by antibiotics in the feed, which is expensive, and consumers are concerned about antibiotic contamination. This project aims to develop a quick, cost-effective test to diagnose enteric septicemia of catfish (ESC), the major cause of mortality from bacterial infection. Following the development of antibodies in experimentally infected fish, a proprietary nutraceutical will be tested. Should it protect fish from infection, it can be produced cost-effectively and avoid the use of antibiotics.

• Chytridiomycosis in amphibians
  Awarded $6,731, Spring 2007
  Source: WFU Science Research Fund

Amphibian populations are declining at alarming rates throughout the world. Since 1987, an estimated 43 percent have been drastically reduced, and 34 species are now extinct. Die-offs are attributed to infection caused by the chytrid fungus, Batrachochytridium dendrobatidis. The project aims to develop two immunological assays to detect the infection in frogs. They will assist in studying the epidemiology of the disease, predicting its future spread, and possibly developing a means to control it.

Anita McCauley

• MRI: Acquisition of Accessories to Upgrade a Confocal Microscope Used for Research and Teaching at WFU
  Awarded $258,251
  Source: NSF

This Major Research Instrumentation award supports acquisition of upgrades for a Zeiss LSM 710 confocal microscope. These accessories now permit live-cell, dynamic, and multilabel experiments and more educational opportunities both on campus and throughout the region.

• Acquisition of a laser scanning confocal microscope for research and training in biology and physics at Wake Forest
  Awarded $385,220 for the period 8/1/07 to 7/31/09
  Source: NSF

The Microscopy Core Facility will acquire an urgently needed laser scanning confocal microscope (LSCM). It will enable faculty, graduate students, and undergraduates to conduct and to publish research on plasticity in the brain, hormonal regulation of proteins in plant roots, stress response systems, gene expression and protein localization in Drosophila, chemoreception and plasticity in the moth antennal lobe, blood clot formation, and optical properties of nanoparticles. Forty percent of biology graduate students use the Core Facility for research; 50 percent take a microscopy course; and this impact will increase with the requested LSCM: ~270 undergraduate students will be exposed to it each year and 11 graduate students will immediately increase their competitiveness with peers at larger institutions. In addition, faculty from three local institutions, including the HBCU Winston-Salem State University, will use the LSCM for undergraduate research and education; it will be incorporated in the Biology department’s multiday symposium, Perspectives in Biology (PIB), which brings together leading researchers and regional faculty from 21 institutions; and it will be part of ongoing community outreach events, including regularly scheduled tours by high-school students from urban and rural NW North Carolina.

• A Stereomicroscope Imaging System for Faculty/Student Research in the Microscopy Core Facility at Wake Forest University
  Awarded $52,999 for the period 5/1/05 to 4/30/08
  Source: NSF

The Biology department has purchased a research-grade, epi-fluorescent stereomicroscope coupled with an image-acquisition and analysis system. These imaging capabilities will enable faculty, graduate students, and undergraduates to conduct research on structure and function, responses to physiological conditions, and gene expression and protein localization in intact, often living organisms and to perform time-apse imaging of animal behavior.

Gloria K. Muday

• Teaching Plant Genetics with Tomatoes
  Awarded $30,000 for the period 8/12/10 to 7/30/12
  Source: American Society of Plant Biologists

This project capitalizes on the popularity of gardening and sustainable food production to teach plant biology to K-12 students. Tomatoes, a familiar and popular food with an intriguing range of fruit forms, colors, and patterns, will be used to demonstrate how genetic changes resulting from spontaneous mutations and human interventions, have profound effects on appearance and taste. Planned exercises are consistent with the North Carolina Standard Course of Study for 3rd, 7th, and 9th grade students and will be broadly disseminated through internet resources. We will also create seed sets with accompanying printed materials that can be sent out to teachers nationwide and establish links between community gardens, where these plants can be grown, and teacher and educational networks.

• Dynamics of auxin transport protein localization and gravitropism
  Awarded $278,728 for the period 8/1/09 to 7/31/12
  Source: National Aeronautics and Space Administration (NASA)

When plants re-orient to gravity either in the laboratory or by accident, asymmetric growth returns them to their original angle, with stems growing up and roots growing down. This project examines the molecular mechanisms that control the directional movement of the hormone auxin. First, a domain tied to endomembrane-targeting will be used to transiently disrupt auxin transport and related protein localization. Second, drugs will be used for the same purpose. Finally, mutants with altered auxin transport will be combined with genetic constructs that allow expression of the missing genes to understand when and how these proteins control auxin transport and gravitropism. Experiments combine high-resolution laser scanning confocal microscopy with high temporal resolution gravitropic analyses.

• Arabidopsis 2010 Project Collaborative Research: Modeling Biological Networks in Arabidopsis through Integration of Genomic, Proteomic, and Metabolomic Data
  Awarded $272,450 for the period 5/1/10 to 4/30/11
  Source: NSF

This Arabidopsis 2010 project brings together six research groups with expertise in phenylpropanoid metabolism and function, genomics, proteomics, metabolomics, computational biology, and computational systems biology to produce a comprehensive map of these functions in Arabidopsis thaliana, a small flowering plant whose genome is one of the smallest and was the first among plants to be sequenced. It has played an important role in understanding flower development and light sensing.

• with Mary Lou Voytko, Neurobiology and Anatomy
  Estrogen modulation of leptin synthesis and signaling
  Awarded $19,936; $16,386 Reynolda Campus, $3,550 Health Sciences
  Source: WFU Cross-Campus Collaborative Research Fund

  The hormone leptin is secreted by adipocytes, and its circulating level is proportional to the abundance of fat deposits. It functions by sending signals to specific receptors in the brain and peripheral tissues that reduce appetite and burn excess fat when stores reach higher-than- normal levels. Rodents and humans with defects in the genes encoding either leptin or leptin receptors have been shown to become morbidly obese, yet how leptin signals are sent and how and why leptin synthesis and signaling vary among individuals are unknown. One clear and consistent difference, found in humans and other mammals, is a much higher blood concentration of leptin in females than males, but little is known about the molecular mechanisms that account for this difference and whether changes in leptin levels are associated with altered leptin responses. A signal likely to enhance leptin synthesis is the female sex hormone estrogen, which is more abundant in females, and whose concentration changes with the female reproductive cycle in parallel with changes in leptin levels. This project aims (1) to determine whether estrogen levels are sufficient to modulate circulating levels of leptin and the soluble leptin receptor in the blood of nonhuman primates; and (2) to alter transcription of the gene encoding leptin and leptin receptor in fat cells grown in culture. Together, these experiments should provide evidence for estrogen control of leptin synthesis and signaling in primates and determine whether the mechanisms include transcriptional changes in the genes encoding leptin and its receptor.

• Ethylene and Auxin Crosstalk in Control of Root Architecture
  Awarded $340,000 for the period 8/15/06 to 8/14/09
  Source: US Department of Agriculture (USDA)

Appropriate root growth orientation and extensive branching are essential for efficient nutrient and moisture retention and maximal plant productivity. Auxin’s importance in regulating these processes has long been appreciated, while a role for ethylene has not been clearly established. This study uses a genetic approach to ask if ethylene regulates root orientation and branching and how crosstalk between auxin and ethylene defines root architecture. Experiments investigate whether elevated levels of ethylene and known ethylene signaling mutants alter root gravitropism and branching in opposite ways, using two agriculturally important species. The genetic model Arabidopsis thaliana and the crop plant Lycopersicon esculentum (tomato) each offer unique experimental advantages. In Arabidopsis, many well-characterized ethylene signaling mutants are available along with reporters and transgenic lines that can be used to examine the molecular mechanisms by which ethylene and auxin signaling interface. Tomato offers a more limited set of ethylene-insensitive mutants and transgenics but has a rapidly expanding research community and set of molecular tools and many agriculturally important members. Examination of hormonal control of root development in two species will help to determine its universality across the plant kingdom.

• Control of Lateral Root Development by Membrane Trafficking Machinery
  Awarded $9,859.80
  Source: WFU Science Research Fund

Asymmetrically localized membrane proteins determine the polarity of the hormone auxin’s movement and modulate plant development. Dr. Muday’s laboratory has isolated a protein that is part of the auxin transport protein and may determine its polar localization. Using the sequences of proteins isolated from affinity chromatography, they have identified a Rab GTPase protein that controls membrane trafficking and may facilitate the formation of polar auxin transport complexes. This project’s goal is to characterize the candidate protein and to determine how it functions to regulate auxin transport and lateral root development.

• With Gary Miller, Health and Exercise Science
  Metabolic Hormone Levels and Obesity, Weight-loss Ability, and Osteoarthritis
  Awarded $10,000
  Source: WFU Science Research Fund

While more than 65 percent of US adults are now considered overweight or obese, neither the cause of this epidemic nor the mechanisms underlying the comorbidities associated with it are understood. Hormones secreted by fat cells, adipocytokines, may provide insight, but their alteration in obesity, osteoarthritis, and older adults and their role in weight loss is not clear. This project will examine levels of these hormones and their receptor for a connection to body weight, osteoarthritis, and weight loss. The overall goal is to understand the metabolic alterations associated with obesity in older adults.

Miles Ross Silman

• Field Laboratory for Integrated Ecosystem Service Science in Upper Amazonian Peru  
  Awarded $238,513 for the period 11/4/10 to 11/15/11
  Source: Gordon and Betty Moore Foundation

A new field laboratory in the Amazon headwaters will advance the highly productive Andes Biodiversity and Ecosystems Research Group (ABERG), a scientific consortium studying integrated ecosystem services and climate change in the tropical Andes/Amazon biodiversity hotspot. Moore Foundation funding played a pivotal role in developing this research program, which subsequently attracted over $5 million in additional funds from the US National Science Foundation, UK Natural Environment Research Council, and others. ABERG’s 40 Peruvian researchers and students and 30 researchers from Europe, the USA and Brazil have generated 36 peer-reviewed publications in major scientific journals, while working out of tents or through the generosity of eco-lodges. The new facility will support fieldwork of global impact at very high cost-efficiency.

• Sensing Approach to Large-Scale Assessment of Carbon Storage in Tropical Forests
  Awarded $178,038 for the period 11/1/09 to 10/31/10
  Source: Blue Moon Fund

As part of its climate-change mitigation strategy, Peru has created a $100 million fund to compensate indigenous people, but it lacks technical support. Many private-sector companies are negotiating carbon contracts, commitments, and deals with stakeholders, including indigenous peoples, Brazil-nut harvesters, private landowners, forestry companies, conservation NGOs, and government agencies, with little or no access to solid data on either biomass, expected deforestation rates, or market prices. For example, the proposed payment of $3.50 per hectare to preserve forests is less than 1 percent of the present value of their carbon. In the absence of this information, flawed agreements are likely to discredit REDD. This project will introduce a new remote sensing technology that allows relatively rapid, accurate computation of total biomass in diverse forest types in the southwest Amazon-Andes region. Results, particularly a publicly available database of carbon and biomass maps, will rationalize market forces.

• Norwegian Climate and Forest Initiative: ACA New REDD Models for Tropical Montane Forest
  Awarded $10,000 for the period 7/24/09 to 1/1/10
  Source: Amazon Conservation Association, Inc.

The eastern slope of the tropical Andes is home to extreme human poverty, world-famous cultural diversity, and world-record biodiversity. Reducing Emissions from Deforestation and Degradation (REDD) programs here offer great opportunities for alleviating poverty, reducing carbon emissions, and test-driving innovative strategies to mitigate the deleterious effects of climate change elsewhere in the tropics. This project works to reforest degraded lands by enriching natural fire breaks with economically valuable Andean species, planted by experienced local foresters and a half-dozen indigenous communities. These agroforestry fire breaks will directly prevent the spread of fire into Manu National Park and adjacent community-held forests, protecting tens of thousands of hectares, while generating REDD enterprise development of nontimber forest products and opening the door for indigenous participation as equals in the growing ecotourism trade. The project includes a strong research component on fire frequency, forest degradation, and carbon cycling in the high Andes and incorporates five other strategies to strengthen REDD programs worldwide.

• Collaborative Research: Determining the Ecological Legacy of Pre-Columbian Human Impacts on Amazonian Ecology
  Awarded $128,124 for the period 4/1/08 to 3/31/11
  Source: NSF

The view that humans exploited and extensively modified the Amazonian ecosystem before 1492 is becoming mainstream in archeological and ecological thought. The widespread use of slash and burn agriculture coupled with “gardening” the forest to enrich the proportion of useful plants may have rendered the region a “cultural parkland” even before contact with the West. However, the evidence is based on extrapolations from major archeological sites. This integrated study will be the first conducted at 18 sites of ecological rather than archeological significance. Beyond tackling one of the most contentious questions in Amazonian ecology, anthropology, and archeology, the data will be of direct relevance to conservation planners, ecologists working with successional systems in tropical forests, and entrepreneurs looking at sustainable and purely extractive uses (logging, crop production, ranching) through land conversion. The project will also provide new data on Amazonian paleoclimates within the last 3000 years, of considerable interest to climate modelers. The team links 7 researchers at as many institutions as well as several undergraduates, 2 graduate students, and a postdoctoral fellow. RET supplements will support the involvement of high school teachers in the research and fieldwork and subsequent development of curricular materials about their experiences.

• Conservation Implications of Climate Change and Fire in the Eastern Andes: Impacts on Plant Distribution and Montane Ecosystems
  Awarded $277,190 for the period 6/1/07 to 7/31/09
  Source: Gordon and Betty Moore Foundation

The eastern slope of the Andes, which harbors Earth’s highest biodiversity, is threatened by climate change. The project investigates 1) the ecology of plant distribution; 2) the relationships between ecosystem and climate; and 3) the historic relationships between plant community ecosystem and climate. Specifically, it focuses on the anthropogenic tree line, the limit to trees caused by human activities, which bars natural plant migration in response to climate change. Resulting data will inform effective conservation strategies.

• Collaborative Research: Understanding the Role of Landcover and Landform in the Spatial Organization of the Diurnal Cycle of Orographic Clouds and Rainfall
  Awarded $127,307 for the period 9/1/07–8/31/10
  Source: NSF

Cloud formation depends on large-scale circulation and local effects of geomorphology and vegetation, which is also highly dependent on it. This project uses two elevation gradients, one in the Himalayas and the other in the tropical Andes. The results will be the first comprehensive look at cloud formation on humid continental mountains and crucial to understanding future ecosystem responses to climate change.

• REU Supplement to Vegetation and Paleoecology of an Amazon-Andean Elevational Transect
  Award $7,443 for the period 5/2/06 to 3/31/07
  Source: NSF

  Funds support the participation of one undergraduate student in a project that seeks to answer a key question in Andean distributional ecology. Its novel methodology for Neotropical pollen analysis, including a field component, a bioinformatics component, using collection data to refine distributional hypotheses, and a lab component at Wake Forest University and Florida Institute of Technology using SEM, Deconvolution Light Microscopy, and automated image analysis, will greatly improve our understanding of both modern species distributional limits and the history of species distributions for a dominant tree genus through the late Pleistocene in the Andes Biodiversity Hotspot. At the cloud forest field station of the Amazon Conservation Association in Peru, the student will work with Dr. Silman, his graduate students, and a Peruvian field crew to collect pollen samples and refine range limits for 11 congeneric species of Weinmannia (Cunonicacae). The student will gain a breadth of experience with international scientists and exposure to diverse topics of study.

Wayne L. Silver

• Can a fruit fly assay be used to screen a cola formula?
  Awarded $10,000 for the period 9/30/09 to 11/2/10
  Source: PepsiCo

The food preferences of Drosophila melanogaster are similar to humans’. A two-choice preference assay, originally developed to measure fruit flies’ sensitivity to sugar and aversion to bitter compounds, which are often toxic, will be used in this pilot project.

• Undergraduate neuroscience training cooperative between WFU and WSSU
  Awarded $199,168 for the period 9/1/10 to 8/31/11
  Source: National Institutes of Health

Although Winston-Salem State University has several active research neuroscientists, the curriculum offers no neuroscience-related courses, so students are inadequately prepared for postgraduate study or careers in the field. UNTRAC: Undergraduate Neuroscience Training Cooperative enrolls WSSU students in WFU undergraduate neuroscience courses; creates research opportunities for them with WSSU, WFU, or WFU School of Medicine neuroscientists; pairs them with graduate student mentors in the WFU Neuroscience Program and enables them to attend a Society for Neuroscience meeting; trains a postdoctoral fellow to assist a WSSU neuroscientist to advance both careers; and evaluates student progress.

• Multiple Mechanisms of Nasal Chemoreception
  Awarded $16,970 for the period 3/1/07 to 2/29/08
  Source: NIH

Most nasal cavity sensitivity to chemicals can be attributed to receptor cells in the main olfactory epithelium that rely on the cAMP transduction cascade. Other mechanisms may be found in trigeminal nerves or solitary chemoreceptor cells. In collaboration with researchers at the University of Colorado Health Sciences Center in Denver and Colorado State University in Fort Collins, experiments will explore alternative chemosensory mechanisms using histological, electrophysiological, and behavioral techniques. Results should improve our understanding of how the nasal cavity processes chemosensory information.

• Facilitation of Birch Seedling Establishment in the Caucasus Mountains
  Awarded $8,998 for the period 4/1/07 to 3/31/09
  Source: Civilian Research and Development Foundation (CRDF); Georgian Research and Development Foundation (GRDF)

This project extends a CRDF/GRDF grant awarded in 2002 and 2005 to study the mechanisms of high-elevation treeline stability. The Georgian group (Institute of Botany, Georgian Academy of Science, FSU) has expertise in distributional ecology, reproductive biology, and seed germination factors in the birch species under study, while the Wake Forest University team has expertise in evaluating the ecophysiology of seedling survival. They will examine ecological facilitation between Betula litwinowii Doluch and Rhododendron caucasicum Pall, focusing on seedling establishment in the Greater Caucasus mountain range. Stunted B. litwinowii forests typically occur at treeline but can be found at high elevations in association with R. causcasicum. The investigators hypothesize that R. causcasicum facilitates B. liweinoii seedling emergence and establishment at these high elevations through several mechanisms. They will test whether (1) photosynthetic carbon gain speeds growth; (2) low carbon gain and reduced root growth result in a desiccation-induced death later in summer, as oils dry following spring runoff; and/or (3) survival is tightly coupled to infection from ectomycorrhizal soil fungi. The results will provide a strong mechanistic explanation for shifts in the maximum altitude at which the intact forest occurs and the expansion or contraction of subalpine and alpine vegetation zones according to global climate change.

• Conserving the Relic Spruce-fir Forests of the Southern Appalachian Mountains
  Awarded $25,000 for the period 6/6/06 to 12/31/06
  Source: Bipartisan Policy Center

Fraser fir exists in only six isolated mountain-top populations in North Carolina, southern Virginia, and eastern Tennessee. The dominant tree at elevations above ~1850 m and interspersed with red spruce between 1650 m and 1850 m, it appears to be a relic species that probably diverged from balsam fir 7-8,000 years ago. While once found at much lower elevations throughout the region and as far south and west as Alabama and Mississippi, during a relatively prolonged period of global warming, it survived only at cooler, higher elevations. Over the last several decades, a significant decline in adult populations has been attributed to an introduced insect, the balsam wooly adelgid, but other contributing factors include drought, ice storms, and deposition of atmospheric pollutants. Regional cloud ceilings have been rising for the past thirty years, and species like the fir and spruce that depend on daily cloud cover and cloud-immersion could be replaced by species more adapted to clear-sky conditions. One study reported that current-year Fraser fir seedlings had substantially reduced photosynthetic capacity and low survival when exposed to full sunlight on clear days. Any disappearance of spruce-fir forest would have dire consequences for wood-related industries, recreational use, snowpack accumulation and water supply to storage reservoirs, and global biodiversity. This forest regeneration model (REGEN) makes specific, quantitative comparisons of new fir and spruce seedling growth and survival that can be coupled with current scenarios of global change effects to predict the chances for regeneration and survival of these relic forest communities.

• Sustaining Barrier Island Ecosystems in a Changing Global Environment
  Awarded $14,338 for the period 4/1/06 to 3/31/07
  Source: NSF

Funds support a workshop to consider the sustainability of barrier island ecosystems under current global change scenarios, including the likelihood of continued human disturbance. These unique ecosystems protect all continental shorelines from powerful wave action. An abundance of highly adapted endemic and indigenous species survive in this stressful environment within the ecotonal transition from land to sea, which may be particularly vulnerable to global change.

• Global Change and Natural Stabilization of Barrier Island Sanddune Ecosystems
  Awarded $8,684 for the period 10/1/05 to 06/30/06
  Source: National Oceanic and Atmospheric Administration (NOAA)

Predictions of future global warming include more intense and frequent weather phenomena, such as tornadoes and hurricanes, and rises in sea level. Little is known about the ecological impact on habitats at high risk to episodic disturbance, like sand dunes, at the interface between the terrestrial and marine biomes, and the possibility of increased extinction rates and loss of biodiversity. This study evaluates the effects of short-term (day-to-day) versus long-term (episodic) stress factors on photosynthetic carbon gain, plant survival, and seed production in five species representing four major categories of plant form and function.

• Ecological Facilitation by Rhododendron caucasicum Extends the Betula litwinowii Alpine Treeline, Caucasus Mountains of Georgia
  Awarded $29,212 for the period 8/1/05 to 7/31/07
  Source: NSF

Ecophysiological studies over the past four decades have failed to evaluate influences on population biology, a major drawback in elucidating evolutionary processes. If current projections of climate warming are accurate, a significant portion of the Earth’s biodiversity will disappear during the next century. In particular, alpine tundra ecosystems in temperate and subtropical latitudes may be replaced by the subalpine forest below. Despite these predictions, a unified mechanistic explanation for the upper elevational limits of subalpine forests across the globe is still controversial. Recent studies are developing a more mechanistic interpretation using ecophysiological measurements of seedling establishment away from the forest edge by the two dominant conifers, Abies lasiocarpa (subalpine fir) and Picea engelmannii (Engelmann spruce). This project will compare the quantitative influences of microsite preference, structural features (leaf to crown), and physiological adjustments on the photoinhibition of photosynthesis (LTP) in the natural environment. It uses two new experimental techniques for the first time. It will measure (1) both external and internal fluorescence and (2) the optical properties of diffuse light absorption to gauge their impact on photosynthesis.

• Ecological Facilitation in the Alpine Treeline Ecotone of Georgia: Implications for Future Global Change
  Awarded $7,000 for the period 1/1/05 to 12/31/07
  Source: CRDF

This investigation is the first comprehensive analysis of the mechanisms dictating alpine treeline stability. It evaluates the fundamental process by which timberlines and treelines migrate either upward into the alpine zone or to lower elevations. Results will provide a strong mechanistic basis for interpreting shifts in the maximum altitude for intact forest and predicting the expansion or contraction of subalpine and alpine vegetation zones in response to global climate changes.

Peter D. Weigl
Evolutionary basis for seasonal sociality in the southern flying squirrel (Glaucomys): resolving the conflict between individualistic and kinship-based explanations
Awarded $9,000, Spring 2007
Source: WFU Science Research Fund

Social behavior and aggregation are critical adaptations for winter survival in many small animals but can exact high energy costs due to food theft by nest mates. The solution may involve the preferential aggregation of genetically related animals, so individuals gain an evolutionary benefit through their relatives, even when they die. The project will measure whether winter aggregations of the seasonally social flying squirrel (Glaucomys) are genetically related.

Clifford Zeyl

• Collaborative research: Genomics of adaptation in experimental yeast populations during short and long-term selection in invasive growth
  Awarded $185,159 for the period 8/1/10 to 7/31/13
  Source: NSF

This project uses whole-genome sequencing to study adaptation in Saccharoyces cerevisiae (budding yeast), focusing on invasive growth, in which cells form chains that penetrate soft surfaces, a key component of virulence in fungal pathogens and often strongly expressed in S. cervisiae strains isolated from human patients. The study will elucidate the mechanisms of an ecologically and medically important trait and advance the fields of experimental evolution, by showing how high-throughput sequencing can monitor standing variation and novel mutations, and molecular evolution, by characterizing the mutations selected during adaptation. Graduate and undergraduate students will apply the newest technologies in genomics research and bioinformatics, and the team will work with a North Carolina School for Science and Math teacher to develop a course exploring evolutionary models relevant to this research.

• Mating Behavior in allopatric and sympatric postzygotically isolated populations of the model Saccharomyces paradoxus
  Awarded $7,000 for the period 4/9/09 to 8/31/10
  Source: NSF

• Mating Behavior in allopatric and sympatric postzygotically isolated populations of the model Saccharomyces paradoxus
  Awarded $205,000 for the period 9/1/08 to 8/31/09
  Source: NSF

Microbial species comprise most of the world’s biodiversity, but because most are difficult to isolate and grow in the lab, very little, if anything, is known about their interactions or the process of speciation. Recent debate about whether populations of microbes, which are very large and migrate easily, vary in the same way as higher plants and animals has cast doubt on whether isolated populations speciate in the same way. Kuehne et al. (2007) described two genetically isolated populations of the wild yeast Saccharomyces Paradoxus that live in the same locations in North America. One seems to have descended from a European migrant. This project will look at the mechanisms underlying the genetic isolation, subjecting individual cells from the co-existing populations as well as cells from the migrant’s ancestral population to a variety of mating assays – a new approach in microbial ecology that will enable us to test classic evolutionary ideas.

• REU: An Exploratory Model for Yeast Population Structure and Dynamics
  Awarded $6,000 for the period 5/21/08 to 1/31/09
  Source: NSF

This supplement to a current NSF award supports summer research for a Wake Forest undergraduate, with the option of continuing in later semesters toward an honors thesis. The project is wide open to innovation, an appealing introduction to research in biology. In addition to making beer, wine, and bread, budding yeast is one of the most important model organisms in cell and molecular biology, genetics, and genomics, yet almost nothing is known about the size of natural yeast populations, their genetic diversity, how they move from one population to another, and the frequency of sexual compared to asexual reproduction among them. This project will introduce genetically marked strains to a structured environment of grapes or figs isolated in fruit fly culture tubes along with fruit flies, which are thought to be a major vector for yeast in nature. The culture tubes will be connected by plastic tubing in a variety of arrangements corresponding to classic models of population structure. In the initial experiments, yeast will be introduced on a single grape or fig, and the other fruits, initially sterile, will be tested for colonization. Subsequent experiments will test for colonization from multiple sources and for mating between strains introduced on separate fruit.

• Evolutionary Advantage, Recombination, and Adaptation in Experimental Yeast Populations
  Awarded $100,000 for the period 11/22/08 to 1/31/10
  Source: NSF

Few of the many conflicting theories advanced to explain the success of sexual reproduction have been tested experimentally. A sexual population’s advantage may be faster adaptation. If so, large populations in a new environment should have an advantage over small or well-adapted populations because more individuals will contain adaptive mutations at the same time. Alternatively, adaptation may require different lineages for different ecological niches, and recombination would produce genotypes not well adapted to any niche. These hypotheses will be tested using one large and one small yeast population, with and without a 2,000-generation history of adaptation to the laboratory environment. Each will start with equal numbers of otherwise identical sexual and asexual strains. A third set of experiments will test populations adapted to the same laboratory environment with the opportunity but not the requirement for sex and recombination. After 50 sexual cycles and 1,000 mitotic generations, recombination rates will be compared to those of ancestral populations. Undergraduate and graduate students will gain education and training in the methods of both classical yeast genetics and molecular genetics and genomics.

• REU Supplement to Population Dynamics and Effect of Sex on Natural Yeast Populations
  Awarded $6,000 for the period 6/12/06 to 1/31/07
  Source: NSF

  The adaptive value of sex has not been well established empirically, despite a great deal of theoretical study. While most yeast evolution is conducted in the lab, where conditions can be standardized and readily controlled, several prominent theories of sex propose that environmental variation, either in space or time, is what favors the genetic diversity of sexual offspring. This project compares the fitness of sexual and asexual yeast populations in their natural environment?on and surrounding oak trees. Genes required for mating and recombination are deleted to produce yeast strains that are incapable of sex but otherwise identical to those found naturally at the experimental location, and their fate is then compared to that of their sexual competitors. It also studies the size and genetic diversity of the natural populations, since very little is known about their ecology, population genetics, and population dynamics. Research Experiences for Undergraduates (REU) supplements support student participation