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Full-Text Articles in Life Sciences
Thylakoid Protein Targeting/Insertion By A Signal Recognition Particle In Chloroplasts, Priyanka Sharma
Thylakoid Protein Targeting/Insertion By A Signal Recognition Particle In Chloroplasts, Priyanka Sharma
Graduate Theses and Dissertations
Protein targeting is a fundamental cellular process that directs proteins from their site of synthesis to the site where they function. The signal recognition particle (SRP) dependent targeting pathway is conserved in both eukaryotes and prokaryotes where it co-translationally targets polypeptide chains emerging from ribosomes to the endoplasmic reticulum (eukaryotes) or cytoplasmic membrane (prokaryotes). A structurally unique form of SRP is found in chloroplasts where it functions to post-translationally bind and target a subset of integral thylakoid membrane proteins, the light harvesting chlorophyll binding proteins (LHCPs). Mature LHCPs bind chlorophyll a/b and function in photosynthetic light capture. Like many other …
An Inventory Of Endemic Leaf Litter Arthropods Of Arkansas With Emphasis On Certain Insect Groups And Diplopoda, Derek Alan Hennen
An Inventory Of Endemic Leaf Litter Arthropods Of Arkansas With Emphasis On Certain Insect Groups And Diplopoda, Derek Alan Hennen
Graduate Theses and Dissertations
Endemic arthropods of Arkansas were sampled and their nomenclature and distributions were updated. The Arkansas endemic species list is updated to 121 species, including 16 species of millipedes. A study of the millipedes of Arkansas was undertaken, and resulted in the first checklist and key to all millipede species in the state. 68 species are known from Arkansas, including the genera Cylindroiulus and Polydesmus. The first state records for Ophyiulus pilosus, Cylindroiulus sp., and Ptyoiulus coveanus are reported, and new county records are reported for 16 species. This represents the first key to a state's species since 1980, and the …
Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan
Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan
Graduate Theses and Dissertations
The primordial Earth which hosted the first forms of life was an environment free of oxygen. Early organisms utilized metabolisms dependent upon anaerobic conditions and incorporated systems to which oxygen is deleterious. As the content of oxygen in Earth's atmosphere increased, anaerobic organisms had to acquire methods to sense and combat oxygen and reactive oxygen species. Several mechanisms were advantageous to such anaerobic organisms which correlated transcriptional processes with the redox state of the cell so that energy may be conserved and oxygen stress recovery genes activated during periods of oxidative stress. Iron sulfur (Fe-S) cluster cofactors incorporated within RNA …
Dlipin-A Link Between Lipid Metabolism, Glucose Homeostasis And Growth In Drosophila Melanogaster, Sandra Schmitt
Dlipin-A Link Between Lipid Metabolism, Glucose Homeostasis And Growth In Drosophila Melanogaster, Sandra Schmitt
Graduate Theses and Dissertations
Lipins are a family of highly conserved proteins found from yeasts to humans. Lipins have dual functions, serving as phosphatidate phosphatase enzymes (PAP) in the synthesis of neutral fats (triacylglycerols, TAG) and as transcriptional co-regulators that affect the expression of genes involved in lipid and fatty acid metabolism. Thus, they play central roles in metabolic control. Disruption of Lipin function has been implicated in lipodystrophy, obesity and insulin resistance. Using dLipin, the Drosophila homolog of Lipin, as a model, I aimed to elucidate the relationship between the two biochemical functions of Lipin and metabolic homeostasis. I discovered there is a …
Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green
Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green
Graduate Theses and Dissertations
Dramatic range-wide declines in Greater Sage-Grouse populations have prompted efforts to determine habitat characteristics that are selected by sage-grouse for foraging, nesting and brood-rearing areas in an effort to conserve this species. Managers at Heart Mountain and Y U Bench in northwestern Wyoming expressed the need to quantify various habitat characteristics and to determine key use areas at both study sites. Data were collected on a variety of habitat variables in spots selected by grouse for foraging, nesting, and brood-rearing activities. These variables were compared to the same variables measured at random points at both study sites. Significant differences existed …
Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga
Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga
Graduate Theses and Dissertations
Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …
Intraspecific Variation In Two Cosmopolitan Myxomycetes, Didymium Squamulosum And Didymium Difforme (Physarales: Didymiaceae), Katherine Elizabeth Winsett
Intraspecific Variation In Two Cosmopolitan Myxomycetes, Didymium Squamulosum And Didymium Difforme (Physarales: Didymiaceae), Katherine Elizabeth Winsett
Graduate Theses and Dissertations
The myxomycetes (plasmodial slime molds or myxogastrids) are one of three groups considered to be true slime molds (class Eumycetozoa sensu Olive 1975). Two vegetative states--amoebae and plasmodia--along with a spore-producing fruiting body characterize the life cycle of the myxomycetes. These organisms are associated with decaying plant material and are found in all terrestrial habitats worldwide. A number of species are considered cosmopolitan, being found worldwide, where they are associated with a diversity of microhabitats and substrates. A review of the literature, including molecular investigations in all three groups of slime molds, is presented, and this is followed by four …
Biogeography And Microhabitat Distribution Of Myxomycetes In High-Elevation Areas Of The Neotropics, Carlos Alonso Rojas-Alvarado
Biogeography And Microhabitat Distribution Of Myxomycetes In High-Elevation Areas Of The Neotropics, Carlos Alonso Rojas-Alvarado
Graduate Theses and Dissertations
Myxomycetes are a group of amoeboid organisms with the capacity of forming fruiting bodies that resemble some macrofungi. The ecology and global distribution of species within the group have been studied only during the last half century. For this reason, a number of questions regarding the nature of the interactions that exist between myxomycetes and their environment still lack the empirical evidence required to obtain complete answers. In the Neotropical region, species assemblages have been moderately well studied, but their biogeography and macroecology have received little attention. In high-elevation areas of this region, the situation is especially precarious, due the …