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Postconflict And Conflict Behavior In All-Male Groups Of Captive Western Lowland Gorillas (Gorilla Gorilla Gorilla), Jackie Elizabeth Davenport Jan 2008

Postconflict And Conflict Behavior In All-Male Groups Of Captive Western Lowland Gorillas (Gorilla Gorilla Gorilla), Jackie Elizabeth Davenport

Retrospective Theses and Dissertations

I studied male western lowland gorillas (Gorilla gorilla gorilla) in a captive setting in order to determine if post-conflict reconciliation exists in male-male dyads of this species. I also examined conflict itself in order to determine the consequences of housing these males together in all-male groups in captivity. This was accomplished by examining the behaviors of nine male gorillas at the Henry-Doorly Zoo in Omaha, Nebraska. Data that I recorded included post-conflict observations, social interactions, and activity budgets. I analyzed the data in order to determine levels of reconciliation, welfare of the population, and comparisons with wild conspecifics. I hypothesized ...


Post-Orbital Color Pattern Variation And The Evolution Of A Radiation Of Turtles (Graptemys), Erin M. Myers Jan 2008

Post-Orbital Color Pattern Variation And The Evolution Of A Radiation Of Turtles (Graptemys), Erin M. Myers

Retrospective Theses and Dissertations

One of the most studied areas in the field of evolutionary biology is the formation and maintenance of new species, as well as variation in the rate and extent to which taxa radiate. A range of evolutionary processes, from ecological adaptation to sexual selection and reinforcement, can lead species formation. However, the generation of new species likely results from several isolating mechanisms acting in concert. The map turtle complex (genus: Graptemys) is an excellent model system for exploring the nature of speciation given its exceptional species richness and morphological diversity, particularly in facial coloration patterns. This research utilizes an integrative ...


Ecology Of Elk Parturition Across Winter Feeding Opportunities In The Brucellosis Endemic Area Of Wyoming, Andrea Ellen Barbknecht Jan 2008

Ecology Of Elk Parturition Across Winter Feeding Opportunities In The Brucellosis Endemic Area Of Wyoming, Andrea Ellen Barbknecht

Retrospective Theses and Dissertations

This study was initiated to examine parturition related behavior both from an ecological perspective and to investigate implications for brucellosis transmission risk among elk and between elk and cattle. These aspects were investigated for elk fed during the winter, elk using improved winter feedlines, and free-ranging elk. Brucellosis is a disease causing abortion in elk ( Cervus elaphus nelsoni), bison (Bos bison), and cattle (Bos spp.). The most common transmission route is through oral contact with aborted fetuses or parturition tissues/fluids and transmission risk is dependent on contact rates. Vaginal implant transmitters were deployed on winter free-ranging elk and elk ...


Small And Large-Scale Landscape Approaches For Conservation Of The Imperiled Blanding's Turtle, Emys Blandingii, Lindsay Marie Carroll Kasuga Jan 2007

Small And Large-Scale Landscape Approaches For Conservation Of The Imperiled Blanding's Turtle, Emys Blandingii, Lindsay Marie Carroll Kasuga

Retrospective Theses and Dissertations

Habitat fragmentation as a result of anthropogenic activities is one of the leading causes of species decline. The wetland habitat specialist, the Blanding's turtle (Emys blandingii), is one chelonian species impacted by habitat fragmentation. This project investigated the impacts of human activities on this species at two levels by first investigating home range and habitat composition, using radio telemetry, for a population of Blanding's turtles in the human-impacted area. The second project was larger in scope, investigating how landscape composition may be influencing the reproductive success of Blanding's turtle populations across the heavily human-impacted state of Iowa ...


Regulation Of Prolactin Secretion In A Nonphotoperiodic Breeder, The Zebra Finch, Debora Ellen Christensen Jan 2007

Regulation Of Prolactin Secretion In A Nonphotoperiodic Breeder, The Zebra Finch, Debora Ellen Christensen

Retrospective Theses and Dissertations

In avian species, high levels of prolactin (PRL) released from the anterior pituitary are associated with reproductive behaviors such as incubation and rearing of young. We studied reproduction-associated PRL levels in breeding and nonbreeding zebra finches. The general hypothesis of this dissertation was: The general pattern of PRL release in zebra finches is similar to other avian species, but differences in regulation of release can be expected due to the unique breeding environment in which these animals live.;The research was divided into four parts: (1) Determining the pattern of PRL release and secretion in response to vasoactive intestinal peptide ...


Taxonomic Review, Phylogeny, And Geographical Population Structure Of The Sawfishes (Chondrichthyes, Pristiformes), Vicente Vieira Faria Jan 2007

Taxonomic Review, Phylogeny, And Geographical Population Structure Of The Sawfishes (Chondrichthyes, Pristiformes), Vicente Vieira Faria

Retrospective Theses and Dissertations

Sawfishes (Pristidae) are considered endangered species worldwide, but their conservation and management have been undermined due to poor understanding of the group's natural taxonomy. The main purpose of this work was to review the taxonomy of sawfishes based on historical taxonomic literature supplemented with empirical observations on morphology, genetics, and geographic distribution. A molecular phylogenetics study based on both mitochondrial and nuclear genes was carried out to estimate the evolutionary interrelationships among the different species of sawfishes. Seven distinct living species are recognized based on external morphology and DNA sequence comparisons. Four are distributed in the Indo-West Pacific, two ...


Behaviorally-Induced Periodic Cooling Of Avian Embryos , Christopher Robin Olson Jan 2006

Behaviorally-Induced Periodic Cooling Of Avian Embryos , Christopher Robin Olson

Retrospective Theses and Dissertations

For many bird embryos, periodic cooling occurs when the incubating adult leaves the nest to forage, but the effects of periodic cooling on embryo growth, yolk use and metabolism are poorly known. To address this question I conducted incubation experiments on eggs of zebra finches (Taeniopygia guttata ) that were frequently cooled and then rewarmed or were allowed to develop at a constant temperature. After 12 days of incubation, embryo mass and yolk reserves were less in eggs that experienced periodic cooling, compared to controls incubated constantly at 37.5°C. Embryos that regularly cooled to 20°C had higher mass-specific ...


Anuran Community Structure And Wetland Occupancy Along An Urban-Rural Gradient In Central Iowa, Usa , Finn Cooper Pillsbury Jan 2006

Anuran Community Structure And Wetland Occupancy Along An Urban-Rural Gradient In Central Iowa, Usa , Finn Cooper Pillsbury

Retrospective Theses and Dissertations

Urbanization has been cited as an important factor in worldwide amphibian declines. Although recent work has illustrated the influence of broad-scale ecological patterns and processes on amphibian populations, little is known about the relative importance of wetland habitat and landscape context on the distribution, abundance, and diversity of anurans in urban landscapes. We therefore examined patterns of anuran community structure and wetland occupancy along an urban-rural gradient in central Iowa, USA. Landscape fragmentation had the strongest influence on anuran community structure, influencing most the abundance of species that use upland habitats outside the breeding season. Urban habitat loss and fragmentation ...


The Importance Of Host Fish In Long Range Transport Of Unionids In Large Rivers , Daelyn Adele Woolnough Jan 2006

The Importance Of Host Fish In Long Range Transport Of Unionids In Large Rivers , Daelyn Adele Woolnough

Retrospective Theses and Dissertations

Freshwater mussels (Family: Unionidae) are the most imperiled faunal group in North America, yet little is known about factors that influence their distribution in rivers and lakes---especially over large geographic areas. They have a unique life cycle that includes an obligate parasite stage on fish. Throughout their life spans, long range or upstream transport is principally accomplished during the parasitic stage. This brief parasitic phase has lasting effects on adult mussel ecology---particularly in influencing their distribution. The movement of host fish occurs on large scales (e.g., >100m) and both their distribution and abundance likely contribute to the spatial patterns ...


Posttranslational Processing And Functional Analysis Of Tractin, An L1 Family Member In Leech , Yingzhi Xu Jan 2003

Posttranslational Processing And Functional Analysis Of Tractin, An L1 Family Member In Leech , Yingzhi Xu

Retrospective Theses and Dissertations

During neurogenesis, glycosylated cell adhesion molecules (CAMs) mediate the growth cone navigation and synapse formation. The structure of neuronal CAMs of Ig superfamily is characterized by the variability and complexity of their extracellular region which contain multiple tandemly arranged domains. The diversity in the structure of the neuronal CAMs is generated by alternative splicing and posttranslational modification, such as differential glycosylation and proteolytic processing.;Tractin is a member of the L1-family of neuronal CAMs in leech. It contains six Ig domains, 4 FNIII-like domains, an acidic domain, 12 repeats of a novel proline- and glycine-rich motif (PG/YG) with sequence ...


Spatial And Temporal Scales Of Distribution And Demography In Breeding Songbirds: Implications Of Habitat Fragmentation And Restoration , Robert J. Fletcher Jr. Jan 2003

Spatial And Temporal Scales Of Distribution And Demography In Breeding Songbirds: Implications Of Habitat Fragmentation And Restoration , Robert J. Fletcher Jr.

Retrospective Theses and Dissertations

Tallgrass prairie has declined throughout the midwestern United States during the past two centuries, and migratory birds breeding in these habitats have also experienced precipitous population declines. One conservation strategy used to mitigate the effects of habitat loss and fragmentation is habitat restoration. I studied how both habitat fragmentation and restoration affect songbird populations breeding in grassland and wetland habitats in northern Iowa, 1999--2002. Most grassland birds tended to be less abundant near edges, yet birds avoided woodland edges more so than other types of edges. Edge avoidance could not be explained by changes in habitat structure. For Bobolinks (Dolichonyx ...


Molecular Phylogenetics And Evolution In Sharks And Fishes , Juan Andrés López Jan 2003

Molecular Phylogenetics And Evolution In Sharks And Fishes , Juan Andrés López

Retrospective Theses and Dissertations

The field of phylogenetic systematics has benefited greatly from advances in the theory that links the variation among organisms to the evolutionary relationships among the biological lineages to which those organisms belong, and from advances in molecular techniques that allow the rapid and easy access to potentially informative data. Despite the clear benefits (e.g. more exacting methodology, increased participation) that these advances have brought to the field, there is widespread disagreement on the confidence that results produced by different methods of phylogenetic inference should be afforded. The disagreement stems in part from the proliferation of ever more sophisticated methods ...


Protein Structure, Distribution Of Homoplasy And Phylogenetic Inference , Olivier Fedrigo Jan 2003

Protein Structure, Distribution Of Homoplasy And Phylogenetic Inference , Olivier Fedrigo

Retrospective Theses and Dissertations

All molecular phylogenetic methods are based on two assumptions: independence of characters and constant selective pressure. It is well known that these assumptions are often violated, but it is assumed that the methods are robust to such violations. However, the increase of unorthodox phylogenies makes us wonder about their reliability. None of the currently used phylogenetic methods and models account for a change of functional/structural constraint at the protein level. In order to understand the consequences on the phylogenetic inference, I studied the distribution of the structural/functional misleading phylogenetic signal in the tree and described the effect of ...


Temperature-Dependent Sex Determination And The Evolutionary Potential For Sex Ratio In The Painted Turtle, Chrysemys Picta , Carrie Lynne Morjan Jan 2002

Temperature-Dependent Sex Determination And The Evolutionary Potential For Sex Ratio In The Painted Turtle, Chrysemys Picta , Carrie Lynne Morjan

Retrospective Theses and Dissertations

Many reptiles exhibit temperature-dependent sex determination (TSD), a sex-determining mechanism in which the incubation environment permanently determines offspring sex. This research had two main objectives: (1) to evaluate the roles of two traits (nesting behavior by females and offspring sex ratios in response to thermal incubation conditions) thought to be important for maintaining sex ratios in this system, using the painted turtle ( Chrysemys picta), and (2) evaluate the adaptive significance of TSD in a genotypic sex determining system (GSD).;Observations on the nesting behavior of painted turtles suggest that either females in this population do not use soil surface temperature ...


Effects Of Environmental Estrogens On Reproductive Biology Of The Fathead Minnow , Robert Bruce Bringolf Jan 2002

Effects Of Environmental Estrogens On Reproductive Biology Of The Fathead Minnow , Robert Bruce Bringolf

Retrospective Theses and Dissertations

Since the early 1990s, environmental estrogens have been recognized as an important environmental threat. Wastewater of 10 aerated lagoon treatment facilities in Iowa was evaluated for estrogenic activity using a short-term caged fathead minnow exposure and a plasma vitellogenin (Vtg) assay. Plasma Vtg results indicated that wastewater entering the three-lagoon systems was estrogenic to male fish, but with serial passage through the lagoons, the estrogenic activity decreased to a level that was not sufficient to induce vitellogenesis. Wastewater retention time in the lagoons may have been a key treatment factor.;Feral fathead minnows captured at aerated lagoon wastewater treatment facilities ...


Physiological And Developmental Gradients In Lumbriculus Variegatus , Nalena Lesiuk Jan 2000

Physiological And Developmental Gradients In Lumbriculus Variegatus , Nalena Lesiuk

Retrospective Theses and Dissertations

Lumbriculus variegatus is known to have external morphological, microanatomical, physiological and behavioral gradients along its body axis. The advantages of using this worm include the possibility of performing behavioral assessment of unique responses, swimming and body reversal, and non-invasive electrophysiological recordings of the nerve conduction. The autotomy reflex in Lumbriculus is an active stereotyped, all-or-none response in which the body is clearly and quickly separated into two fragments. The response consists of formation of lateral fissure in the body just anterior to the compression site and became circumferential. After the autotomy, the exposed terminal surfaces of both anterior and posterior ...


The Influence Of Habitat Features On Grassland Birds Nesting In The Prairie Pothole Region Of North Dakota , David Joseph Horn Jan 2000

The Influence Of Habitat Features On Grassland Birds Nesting In The Prairie Pothole Region Of North Dakota , David Joseph Horn

Retrospective Theses and Dissertations

Results of habitat fragmentation studies on grassland and wetland birds are not consistent. Some studies have found positive relationships among abundance, nest success, field size, and distance to edges, whereas others have found no relationship. One reason for differing results may be the landscape composition in which the study took place. I examined how landscape composition influenced relations among: (1) occurrence and abundance of grassland songbirds and field size, and (2) nest success of ducks, field size, and edges. I also investigated the effects of mowing on grassland songbirds, and how landscape features, such as amount of perennial grassland, and ...


The Influence Of Vegetation And Landscape On The Forest Bird Community Of Northeast Iowa , William Russell Norris Jan 1999

The Influence Of Vegetation And Landscape On The Forest Bird Community Of Northeast Iowa , William Russell Norris

Retrospective Theses and Dissertations

I studied bird community dynamics and habitat associations of forest birds in northeast Iowa in 1995 and 1996. During this study, 107 different bird species were detected in northeast Iowa forests, including many neotropical migrant songbirds. However, a nest parasite, the brown-headed cowbird ( Molothrus ater), was the most frequently detected bird during this study. The abundance and species richness of birds (both expressed as mean numbers per bird census point at each site) were both higher in 1995 but the rank orders of bird species in 1995 and 1996 were highly correlated, suggesting stable bird community structure over time;Most ...


The Use Of Anuran Larvae To Determine Chronic And Acute Toxicological Effects From Exposure To Atrazine And Metolachlor , Linda Suzanne Gucciardo Jan 1999

The Use Of Anuran Larvae To Determine Chronic And Acute Toxicological Effects From Exposure To Atrazine And Metolachlor , Linda Suzanne Gucciardo

Retrospective Theses and Dissertations

This research investigated the effects of chronic exposure of amphibian tadpoles and acute exposure of embryos to the agricultural chemical atrazine;Tadpoles were chronically exposed from the first feeding stage through metamorphosis to three levels of atrazine. Concentrations of 30, 300 and 600 mug/L reflect exposures likely to occur in streams, wetlands and temporary waters near croplands. Cricket frogs (Acris crepitans), wood frogs (Rana sylvatica) and northern leopard frogs (R. pipiens ) were evaluated on rate of growth, days to metamorphosis, metamorphic success, and juvenile weight and length. A repeated measures ANOVA evaluated the rate of growth (increase in SVL ...


Egg Water Exchange And Temperature Dependent Sex Determination In The Common Snapping Turtle Chelydra Serpentina , David Bryan Lott Jan 1998

Egg Water Exchange And Temperature Dependent Sex Determination In The Common Snapping Turtle Chelydra Serpentina , David Bryan Lott

Retrospective Theses and Dissertations

The effect of varying substrate moisture contents and incubation temperatures on developing snapping turtle embryos was addressed. Mass change was measured for several clutches of snapping turtle eggs within field nests. Throughout the incubation period, a subset of the total number of nests was measured on either a weekly or a bi-monthly interval. Mass of each egg within a particular nest was separately weighed and inspected. Nest microclimate measurements, such as soil water potential and volumetric water content, were also measured on a regular basis. The patterns of egg mass change, which have previously been determined to be due to ...


Gene Flow At A Snail's Pace: Phylogeography And Conservation Genetics Of Relict Populations Of The Iowa Pleistocene Snail , Tamara Kay Ross Jan 1998

Gene Flow At A Snail's Pace: Phylogeography And Conservation Genetics Of Relict Populations Of The Iowa Pleistocene Snail , Tamara Kay Ross

Retrospective Theses and Dissertations

The Iowa Pleistocene snail, Discus macclintocki, is a federally endangered land snail found only in northeast Iowa and northwestern Illinois. This species is believed to be a glacial relict with populations isolated for the last 16,000 years. In this study, I investigated the amount of genetic variation within, and the gene flow among, ten isolated populations of the Iowa Pleistocene snail, Discus macclintocki (Baker). I sequenced part of the 16s region of the mitochondrial DNA from 175 snails. Populations clustered clearly by watershed, suggesting that flooding events may have been the historical avenue of gene flow rather than overland ...


Pou Domain Genes And The Immunoglobulin Octamer Motif In Chickens , Lynn Marie Heltemes Jan 1997

Pou Domain Genes And The Immunoglobulin Octamer Motif In Chickens , Lynn Marie Heltemes

Retrospective Theses and Dissertations

This research was undertaken to test the hypothesis that multiple POU genes exist and that POU proteins are involved in transcriptional regulation in the chicken. The POU protein Oct-2 has been hypothesized to partially regulate immunoglobulin gene expression through its interaction with the octamer motif found in the promoter of immunoglobulin genes. Transcriptional regulation of immunoglobulin genes provides a model for tissue-specific gene expression in the immune system. In searching for a chicken Oct-2 homologue, two partial chicken POU domain genes were identified. A cDNA clone encoding the POU domain of Brn-3a was isolated and showed near identity to the ...


Characterization Of The Developing Facial And Hypoglossal Motor Systems In The Neonatal Brazilian Opossum , Jack Jeffrey Swanson Jan 1997

Characterization Of The Developing Facial And Hypoglossal Motor Systems In The Neonatal Brazilian Opossum , Jack Jeffrey Swanson

Retrospective Theses and Dissertations

Aspects of development of the facial and hypoglossal motor systems were investigated in the neonatal Brazilian opossum, Monodelphis domestica. Monodelphis is a small pouchless marsupial whose young are born after 14 days of gestation in an extremely immature state while neurogenesis is still ongoing;1. The developmental time course for synaptogenesis in the facial motor nucleus (FMN) and the hypoglossal motor nucleus (HMN) was examined using immunohistochemistry against: synaptic vesicle-associated proteins, synaptophysin and synaptotagmin; a synaptic membrane protein, SNAP-25; a growth cone protein, GAP-43; and microtubule-associated proteins, Tau-1 and MAP-2. We found that appearance of synapse-associated proteins is delayed in ...


The Foraging Behavior Of Anax Junius (Odonata: Aeschnidae) And Its Potential As A Behavioral Endpoint In Pesticide Testing , Sandra Kaye Brewer Jan 1997

The Foraging Behavior Of Anax Junius (Odonata: Aeschnidae) And Its Potential As A Behavioral Endpoint In Pesticide Testing , Sandra Kaye Brewer

Retrospective Theses and Dissertations

I examined the foraging behavior of the green darner dragonfly nymph, Anax junius, to assess the suitability of odonate foraging behavior as a sensitive endpoint for monitoring contaminant exposure. Odonates are potentially excellent organisms for work in biomonitoring programs because: (1) they have complex foraging strategies that tightly couple sensory cues and mechanical responses: (2) their ecology is well-studied: and (3) they are often the dominant invertebrate predator in fishless systems. Thus they have the potential to structure communities through predation;I tested (1) the possibility that nymphs may regulate populations through frequency-dependent foraging and (2) the relationship between head ...


Regulation Of Intracellular Calcium Release During Fertilization In Sea Urchin Eggs , Shyh-Jye Lee Jan 1997

Regulation Of Intracellular Calcium Release During Fertilization In Sea Urchin Eggs , Shyh-Jye Lee

Retrospective Theses and Dissertations

The requirement for both inositol-1,4,5 trisphosphate (InsP3) and ryanodine-sensitive intracellular Ca2+ release mechanisms during fertilization was studied in sea urchin eggs. The postulated pathway of cGMP-dependent protein kinase (PKG) activation of ADP-ribosyl cyclase for production of cADPR to activate the ryanodine receptor Ca2+ channel was tested with a variety of activators and inhibitors. Our observations are consistent with Ca2+ release by cGMP in the egg being dependent on an isoform of PKG that is distinct from the mammalian enzyme. PKG activity in the sea urchin egg was activated by cIMP and was insensitive to cGMP analogs, which are ...


Astrocyte Volume Regulation , Trent Allan Basarsky Jan 1996

Astrocyte Volume Regulation , Trent Allan Basarsky

Retrospective Theses and Dissertations

This dissertation deals with the regulation of synapse formation between cultured hippocampal neurons, and the volume dynamics of astrocytes during hyposmotic-induced swelling;The developmental time course of synapse formation in cultured hippocampal neurons was examined. After 12 days in culture (DIC) inhibitory and excitatory synapses formed which were sensitive to the N-type calcium channel antagonist [omega]-conotoxin GVIA ([omega]-CgTx) while, at 4 DIC, immature connections were present in which spontaneous, but rarely evoked, synaptic currents were detected. A comparison of 4 and 12 DIC neurons revealed the presence of the synaptic proteins rab3a, synapsin I, and synaptotagmin, but the ...


The Role Of Rat Brain Ptp-1 Surface Basic Residues In Substrate Reactivity , Deborah Sue Baedke Jan 1996

The Role Of Rat Brain Ptp-1 Surface Basic Residues In Substrate Reactivity , Deborah Sue Baedke

Retrospective Theses and Dissertations

Previous work by others has demonstrated that rat brain protein tyrosine phosphatase (rbPTP-1) exhibited increased reactivity toward substrates containing acidic residues N-terminal to phosphotyrosine. We show that substrates containing a single acidic residue C-terminal to the phosphotyrosine also enhanced reactivity with rbPTP-1. A substrate aspartate residue at the P+2 position exhibited the greatest enhancement of reactivity;Surface basic residues of rbPTP-1 were investigated for their role in the increased reactivity due to substrate acidic residues. Mutation of R47 or K120 to alanine decreased the enhancement of reactivity due to acidic residues N-terminal to phosphotyrosine by 78% and 73% respectively ...


Water Exchange In Reptile Eggs: Mechanism For Transportation, Driving Forces Behind Movement, And The Effects On Hatchling Size , Todd Alan Rimkus Jan 1996

Water Exchange In Reptile Eggs: Mechanism For Transportation, Driving Forces Behind Movement, And The Effects On Hatchling Size , Todd Alan Rimkus

Retrospective Theses and Dissertations

The mechanism for water transport in reptile eggs is examined with particular interest in the phase water is in while being exchanged. Eggs were examined at various times during the incubation. A non-volatile dye was used as an indicator of liquid water movement. Presence of the dye after 48 hours of exposure may be indicative of liquid water movement. If the egg changes mass and no dye is present the water was considered to be exchanged in the vapor phase. Eggs exposed to the dye early during incubation took up the dye, while eggs exposed after day ten have dye ...


Territorial Behavior Of The Red Admiral Butterfly, Vanessa Atalanta (L.) (Lepidoptera: Nymphalidae) , Royce Justin Bitzer Jan 1995

Territorial Behavior Of The Red Admiral Butterfly, Vanessa Atalanta (L.) (Lepidoptera: Nymphalidae) , Royce Justin Bitzer

Retrospective Theses and Dissertations

This study of territorial behavior in the nymphalid butterfly Vanessa atalanta examines a number of behavioral and climatic factors shaping how, when, and for how long males maintain territories during the late afternoons of late spring and summer. Territorial V. atalanta males were observed on the Iowa State University campus from early April/early May to late August/early September from 1987 to 1992 on a total of 224 days. Microclimatic conditions were simultaneously recorded with automatic datalogging equipment. Males started territorial activity later on warmer days and when the ground was cooler, under all types of cloud cover. Although ...


The Role Of D-Raf In The Terminal Class Signal Transduction Pathway In Drosophila Melanogaster , Kwang-Hyun Baek Jan 1995

The Role Of D-Raf In The Terminal Class Signal Transduction Pathway In Drosophila Melanogaster , Kwang-Hyun Baek

Retrospective Theses and Dissertations

This dissertation describes the characterization of D-raf-mediated signal transduction in the establishment and elaboration of pattern in Drosophila melanogaster. D- raf is the Drosophila homologue of the human Raf-1 proto-oncogene. As a member of the Drosophila Torso (Tor) signal transduction cascade, D-raf acts to define cellular fates at the embryonic poles. Here we show that the serine/threonine kinase activity of D-raf is required for propagation of the Tor signal and that human Raf-1 can substitute for D-raf in this pathway. We identified two serine phosphorylation sites (S388 and S743) and found that serine or its phosphorylation at site 743 ...