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Does the Misregulation of Codon-Biased Genes in the Anterior Pituitary Contribute to Familial Dysautonomia?
Get PDFFamilial Dysautonomia (FD) is a devastating neurodevelopmental and neurodegenerative childhood disease characterized by a diminished number of autonomic neurons. FD children suffer from a multitude of autonomic symptoms including cardiovascular instability, gastrointestinal incoordination, and respiratory dysfunction. FD patients also exhibit an abnormal autonomic stress response, tend to be small in stature, and have difficulty gaining and maintaining weight. FD results from a mutation in the IKBKAP gene and diminished levels of the corresponding protein IKAP, a scaffold that assembles the multi-subunit complex, Elongator. Elongator functions in the modification of tRNAs that mediate translation of AA- and AG-ending codons. IKAP is expressed throughout the autonomic nervous system and historically FD symptoms have been attributed to autonomic dysfunction. Here we show that IKAP is also robustly expressed in the pituitary gland, both during development and in the adult. We hypothesize that many FD symptoms may actually result from aberrant pituitary regulation of the autonomic nervous system. To test this hypothesis we are currently generating a conditional knockout mouse where Ikbkap will be selectively ablated in the anterior pituitary. While waiting for our mouse model, we have been optimizing techniques for quantifying pituitary specific genes that are likely candidates for Elongator regulation based on their content of AA- and AG-ending codons
Endoplasmic Renticulum-Activated C/EBP Homologous Protein Mediates the Palmitate-Enriched Diet Induced Increase in the Lipogenic Expression in the Liver
Get PDFNon-alcoholic fatty liver disease (NAFLD) is a wide spectrum pathophysiological disorder characterized by insulin resistance, hepatic steatosis, and inflammation. Diets rich in saturated fat are known to evoke insulin resistance, ER stress, and de novo lipogenesis and thereby contribute to the pathogenic mechanisms involved in NAFLD. Palmitic acid (palmitate) is the most abundant saturated fatty acid in the diet and palmitate-enriched diets are known to cause NAFLD in a multitude of rodent models of NAFLD. Palmitate-enriched diets are known to induce steatosis by inducing the expression of genes involved in de novo lipogenesis. However, the signaling mechanisms and the downstream molecular mediators involved have not been elucidated. In this study, we explored the role of palmitate-induced ER stress and subsequent induction of C/EBP Homologous Protein (CHOP) expression in the modulation of expression and transcriptional activities of Liver X Receptor alpha (LXR?) and Sterol Response Element Binding Protein 1c (SREBP1c), two indispensable transcription factors and master regulators of genes involved in de novo lipogenesis. We demonstrate, in exogenous palmitate-treated HepG2 cells and in the livers of palmitate-enriched diet-fed mice, that palmitate evokes ER stress leading to the induction of CHOP expression. We further show that CHOP mediates the up-regulation in expression levels and transcriptional activities of LXR? and SREBP1c. Our study identifies a unique ER stress-CHOP-LXR?/SREBP1c signaling pathway that mediates palmitate-induced up-regulation of lipogenic gene expression in the liver that may play a critical role in the etiopathogenesis of NAFLD
Monitoring Hoary Marmots: Matching Objectives to Available Effort
Get PDFMonitoring provides information necessary for managers to make informed decisions related to the status of populations. However, collecting sufficient data to reliably detect trends in abundance over a large area is costly in time and resources. Instead, detecting changes in distribution may be a more feasible goal, while still providing useful information. Hoary marmots are alpine obligates, patchily distributed throughout the mountains of western North America. This species requires deep winter snowpack to survive during winter and populations at the edges of their distribution are most likely to be vulnerable to changes in climate. We sought to design a monitoring plan that could identify changes in distribution of hoary marmot populations. We used occupancy methods to create a predictive habitat map for hoary marmots in western Montana. We evaluated designs that could be implemented by existing staff or with 2 dedicated technicians and assessed tradeoffs in the number of sites and surveys needed to detect a change in distribution. We also evaluated the effort needed to sample throughout Montana or within selected mountain ranges. Based on our analyses, managers will need to complete surveys at ?65 sites at least twice a season and without dedicated technicians, the area sampled will be limited. Hoary marmots likely will be negatively impacted by climate change, especially in isolated mountain ranges at the southern extent of their distribution. Assessing the magnitude of these changes will be impossible without sufficient data, highlighting the importance of identifying monitoring objectives before data collection begins
Montana's IMBCR Program: Utility of Seven Years of Statewide Landbird Monitoring Data
Get PDFThe 2016 field season marks the 7th consecutive year of statewide implementation of the Integrated Monitoring in Bird Conservation Regions program (IMBCR) for monitoring bird populations in the state of Montana. Using a spatially-balanced, hierarchical study design, the IMBCR program provides density and occupancy estimates for bird species at various geographic extents (strata) across the western U.S. Based largely on agency investment, primary sampling occurs in all USFS R1 National Forests and extensive grassland/sagebrush habitats on Montana BLM lands statewide. Significant sampling also occurs in various habitats on private lands. Using these data, as well as tools available on the Rocky Mountain Avian Data Center web console, agencies and NGO partners can evaluate avian distribution and population dynamics statewide. As an effective monitoring program, the IMBCR program informs research questions, landscape-level management and conservation action. The design and current applications of the IMBCR program are summarized
Harvest and Non-Harvest Mortality Relationships for Lesser Scaup Breeding in Southwestern Montana
Get PDFSince the mid-to-late 1990s, lesser scaup (Aythya affinis) populations have remained more than 20% below the population goal set forth in the North American Waterfowl Management Plan. Accordingly, considerable attention has been directed towards understanding what factors may be limiting their population, including the role of harvest. Red Rock Lakes National Wildlife Refuge (RRL) in southwestern Montana is the site of a long-term study of lesser scaup ecology and demography with data from which survival and harvest rates can be estimated using capture-mark-recapture statistical techniques. The role of harvest in regulating duck population dynamics, including lesser scaup, is clouded with uncertainty. Decades of research into the additive or compensatory nature of harvest mortality has yielded little consensus as to which of these hypotheses prevail in North American duck populations. The most limiting factor to assessing these relationships stems from lacking estimates of population size during waterfowl hunting seasons. We assessed the relationship between survival rates and harvest rates for lesser scaup females breeding at RRL for an 11 years, beginning in 2005. Consistent with predictions of density dependence regulation of natural mortality rates during the non-breeding season, we found evidence suggesting adult female survival rates fluctuate in response to harvest regulations, an index of population size, and the total number of lesser scaup harvested in the Pacific and Central Flyways
Responses of Songbird Population to Cattle Grazing Regimes in Sagebrush-Steppe of Eastern Montana
Get PDFSagebrush-steppe ecosystems in western US are characterized as a landscape mix of sagebrush shrubs and grass vegetation. A large portion of sagebrush-steppe across the west is used for grazing of domestic livestock, primarily cattle. We compared songbird communities over four breeding seasons in eastern Montana between two grazing systems: rest-rotation and traditional grazing. Rest-rotation involves grazing areas (or pastures) at different annual seasons across years allowing pastures to be rested between the same consecutive seasons. Traditional grazing is defined as grazing a pasture repeatedly at the same annual season each year. Recently, rest-rotation has been used as a conservation management tool by the Natural Resource Conservation Service’s (NRCS) Sage Grouse Initiative (SGI) program. The goal is to improve habitat for greater sage grouse (Centrocercus urophasianus) through livestock grazing. We explore the effects of rest-rotation compared to traditional grazing on songbird population breeding demographics: adult abundance, nest densities and nest success. Abundance is a metric often used to assess conservation actions given the ease in collecting data to estimate this parameter. However, information on how the conservation actions influences the life histories, such as nest density and nest success, that determine abundance are lacking. Our goal is to understand the relationship between patterns in abundance, nest density, and nest success and how rest-rotation grazing influences those patterns. This knowledge will provide information on how to best manage for multiple songbird species in sagebrush-steppe by determining how conservation management tool affects individual songbird populations
Rabbit Creek: Geochemistry of an Alkaline Deeply Sourced Hot Spring with Abundant Microbial Mats
Get PDFThe Rabbit Creek hot springs in Yellowstone National Park are located along the edge of the Mallard Lake Dome in the Midway Geyser Basin. The principal source, Rabbit Creek hot spring, contains high concentrations of arsenic and antimony relative to hot springs throughout the area. This study investigates the water chemistry of the Rabbit Creek hot spring outflow, geologic explanations for the distinct differences in hot spring compositions of the area, and the implications for the abundant thermophilic microbial mats present in the outflow. The distribution of the microbial mats may be related to the concentrations of arsenic and antimony throughout the outflow. In addition, changes in the microbial mats related to temperature and sulfide concentrations are discussed. This study aids in our understanding of the hot springs in the Rabbit Creek area and of the potential effects of the Mallard Lake Dome on the Midway Geyser Basin
Amphibian Risk Assessment in Montana
Get PDFThe fungus, Batrachochytrium dendrobatidis, has been found to negatively impact amphibian populations around the world. This fungus can have multiple effects on frogs and salamander physiology, including changes in osmotic regulation that may lead to death. B. dendrobatidis has been shown to be the driving force for many amphibian population crashes and extinctions around the world. The purpose of this project was to build a predictive model of B. dendrobatidis infection, one that would be used to assess population susceptibility in order to identify populations of amphibians at risk of infection. This was accomplished by statistical analyses of several components that contribute to infection vulnerability, including amphibian antimicrobial peptide production, cutaneous bacterial colony structure, infection status for each frog and water nutrient composition. This project collected baseline data that will allow us to establish meaningful relationships between susceptibility factors and disease which will permit the identification of populations at risk. Although certifications may not provide a comprehensive solution to the challenges facing women in Costa Rica’s coffee industry, the majority of women feel empowered through involvement in local organizations and women’s groups. This research adds new perspectives to the growing body of literature regarding the efficacy of coffee certification schemes and has implications for certification agencies and local-level organizations in Costa Rica and other coffee producing countries
Rhetoric, Visual Rhetoric, and the 1950’S Betty Crocker Cookbooks
Get PDFThis study explores the importance of Betty Crocker to her cookbooks in the 1950’s. The Betty Crocker Cookbook was an instruction manual that fits within a particular genre of technical communication. These technical manuals included instruction for women on how to prepare and cook aesthetically pleasing and wholesome meals. The Betty Crocker Cookbook went beyond established norms of cookbook instruction by adding helpful hints on how to be a perfect housewife. Rhetorical and visual analysis of the 1950’s Betty Crocker Cookbooks shows the importance of these particular cookbooks was Betty Crocker herself. Because she was an authority on all things pertaining to the kitchen, women accepted this authority, in part because of the ethos of Betty Crocker, a trusted figure and someone they felt a relationship with. She was with them through the Great Depression and World War II, and she was the voice on the radio that brought a sense of normalcy in a turbulent time, the fact that Betty Crocker was a fictional construct did not matter
Wind Energy Development in Montana: Guidance for Effective Agency Involvement to Minimize Wildlife Impacts
Get PDFMontana is one of the top five states for wind energy potential but ranks 19th for installed wind energy, with 691 megawatts of capacity built. Nationwide, wind energy development is on track to provide 20% of the country’s electricity by 2030 and wind turbine technician is the fastest growing job in the nation. Wildlife managers in Montana will see more wind development projects come across their desks but may have limited experience with review. We present an overview of existing and potential wind farms in Montana and the typical process for project permitting and development. Wind has great potential as a source for green energy but improperly sited wind projects pose threats to wildlife including potential risk of bird and bat collisions; displacement of nesting raptors, songbirds, and prairie grouse at leks; and habitat fragmentation. In 2015, Montana Fish, Wildlife and Parks began wildlife monitoring at a wind farm near Geyser, giving the department direct experience designing and implementing fatality monitoring. The key to wildlife friendly wind development is early consultation with state and federal agencies and open discussion of survey results. To assist developers, USFWS has produced the Wind Energy Guidelines (WEG) and Eagle Conservation Plan Guidance (ECP). These are voluntary guidelines, but both aim to walk developers through the process of identifying, avoiding, and minimizing impacts to wildlife and key habitats. To assist biologists, we will summarize impacts to wildlife, give a short-course on the WEG and ECP, identify opportunities for agency involvement at each stage of development and offer a framework for effective consultations