Life Sciences Commons^™

Trimethylated Lysine 4 At Histone 3 Shows The Same Circadian Rhythm At Promoters Of Diversely-Expressed Genes In Chlamydomonas Reinhardtii, Robyn M. Wilson

Masters Theses & Specialist Projects

Circadian clocks are biochemical mechanisms that allow eukaryotic and some prokaryotic organisms to coordinate their physiology with daily environmental changes. It enables organisms to increase their fitness by taking advantage of beneficial environmental conditions while also avoiding or restricting certain sensitive processes during harsh conditions. Similarly, post-translational histone modifications allow eukaryotic organisms to regulate gene expression in response to environmental or developmental factors. Some post-translational modifications of histones are associated with active transcription while others are associated with repressed transcription depending upon the location, type and degree of modification. Trimethylation of lysine 4 on the N-terminal tail of histone H3 …

Heterologous Expression Of Arabidopsis Thaliana Purple Acid Phosphatase Gene (Atpap15) In Crops For Phytoremediation Of Sites Contaminated With Excess Phosphorus, Jane Jeruto Bartonjo

Masters Theses & Specialist Projects

AtPAP15 is one of the purple acid phosphatases expressed by Arabidopsis thaliana that has been extensively studied. Purified AtPAP15 has been shown to exhibit both phytase and phosphomonoesterase activities in acidic pH with maximal activity at pH 4.5. AtPAP15 is a phosphorus starvation inducible (PSI) gene that is expressed highly during phosphorus deficient conditions. In the current study, AtPAP15 was overexpressed in Nicotiana tabaccum under cauliflower mosaic virus (CaMV35S) constitutive promoter. After PCR confirmation of the gene, plants were transferred to the greenhouse and allowed to grow in pots. The pots contained Sta-Green potting mix (Lowe’s Inc., Mooresville, North Carolina,U.S.). …

Relationships Among Rubus (Rosaceae) Species Used In Traditional Chinese Medicine, Yinu Wang

Masters Theses & Specialist Projects

Traditional Chinese medicine has a long history of using plants therapeutically including multiple species of the genus Rubus (Rosaceae). Fruits and other parts of Rubus plants have had a significant effect on human health and nutrition in both ancient and modern times. The pharmacological effects of Rubus include anti-inflammatory, antibacterial, anti-stress, anti-cancer and anti-aging properties. One of the current challenges limiting further development of Rubus resources in traditional Chinese medicine is a poor understanding of phylogenetic relationships among Rubus species in general and especially among Asian species, and also the need for additional studies of phytochemicals. Several confounding factors are …

Generation Of Transgenic Medicago Sativa Overexpressing "Osmotin-Chitinase" Gene Chimera, Jahnavi Reddy Kancharla

Masters Theses & Specialist Projects

Medicago is widely used as a forage crop. It is often susceptible to various pathogenic infections and exhibits low growth in drought and extreme climatic conditions. In the current study, a strategy was developed for over-expressing an “Osmotin-Chitinase” gene chimera in transgenic Medicago that could potentially confer resistance to different biotic and abiotic stresses. Seed germination of several cultivars of Medicago (M. sativa ssp. sativa, M. sativa ssp. falcata, M. sativa ssp. caerulea, M. truncatula, and M. Rugosa) was tested to determine the cultivars with good germination rates. Among these, M. sativa ssp. sativa showed an …

Reestablishing Diversity In Our Hardwood Forests: A Transplant Study Of Five Spring-Flowering Herbs, Danielle Racke

Masters Theses & Specialist Projects

Herbaceous communities are critical to the functioning of forest ecosystems. They recycle nutrients, help prevent erosion, provide critical microhabitats and maintain biodiversity. In the eastern United States, most hardwood forests are growing on land once entirely cleared or used for some form of agriculture. Although some of these forests are nearly 150 years old, they still have depauperate native herbaceous communities when compared to remaining old-growth forests. This long-term depletion may result from dispersal limitation or environmental limitation.

I tested the hypothesis that dispersal was the primary factor contributing to the absence of five spring-flowering herbaceous species in four secondary …

Genetic Diversity In Native And Invasive Rubus (Rosaceae), Ashley A. Wint

Masters Theses & Specialist Projects

Invasive species are an increasing threat to biological diversity as well as a leading cause of recent species’ extinctions. Invasives spread quickly and efficiently, and the U.S spends millions of dollars annually in the control and eradication of these species. More information is necessary in order to predict which species may become invasive. Rubus (Rosaceae) was chosen for study because this genus includes various ploidy levels, reproductive modes, and species that are invasive as well as native.

Three Rubus species were chosen to represent apomictic and tetraploid invasives (Rubus armeniacus), a sexual and diploid native species (R. occidentalis), and a …

The Short-Term Effects Of Manganese Toxicity On Ribulose 1,5 Biophosphate Carboxylase In Tobacco Chloroplasts, Kerrie Elliott

Masters Theses & Specialist Projects

The short-term effects of manganese toxicity on ribulose 1,5 bisphosphate carboxylase (Rubisco) activity and concentration in tobacco chloroplasts were examined. The activity of the enzyme from both manganese-treated and control plants was determined 6, 12, 18, 24 , and 48 h after introduction of manganese (80 mg/Li. Enzyme activity was determined by monitoring rates of radioactive CO₂ fixation into acid stable products. A slight stimulation of the enzyme's activity was noted in experimental plants after 18 h of exposure to manganese as compared with control plants. A decrease in the enzyme's activity in experimental plants was noted after 48 …

Phenotypic Differences In Populations Of Euonymus Americanus L. From The Central United States & Autecological Studies Of This Species In A Deciduous Forest Of Kentucky, Paul Bayer

Masters Theses & Specialist Projects

The concentrations of sodium and potassium in the leaves of Euonymus americanus collected from a relict hardwood forest during a four month period showed a possible winter conditioning pattern. Seeds collected from this same relict stand would not germinate, even though they were subjected to a wide variety of germination experiments. Phenotypic differentiation in fully developed leaves was not found; however, differences related to the length of the growing season were noted. Autecological studies of Euonymus americanus should be continued to investigate the role of this plant in relict hardwood stands.

Ecotypic Differentiation Of Andropogon Virginicus L. In Relation To Strip Mine Spoil Banks, Valina Kay Hurt

Masters Theses & Specialist Projects

Reciprocal plantings of populations of broomsedge, taken from an abandoned strip mine and from an abandoned farm plot in south central Kentucky, on strip mine spoil and abandoned field soil resulted in patterns of populations differentiation. Clonal plantings of populations from strip mine habitats and old field development appeared equal in height and biomass when grown on old field soils in both field trials and growth chamber studies. Populations when planted in strip mine soils in field trials and controlled growth experiments. Later flowering in strip mine populations may be a key to survival strategy in the harsh microclimates of …

A Taxonomic & Physiographic Survey Of Scirpus In Kentucky With Problem Species Complex Analysis, Sally Arnold

Masters Theses & Specialist Projects

The genus Scirpus was analyzed according to species occurrence and physiographic distribution in the State of Kentucky. The morphology of three taxonomic problem complexes, Scirpus atrovirens-georgianus, Scirpus validus-acutus, and Scirpus cyperinus-eriophorum-pelius-pedicellatus was evaluated to determine whether or not their components are distinct among the Kentucky specimens. Remaining taxa were likewise evaluated and identified. A key to Scirpus in Kentucky and a taxonomic treatment are presented.

Cause And Control Of A Common Market Disease Of Lettuce, William Palmore

Masters Theses & Specialist Projects

Head lettuce, Lactuta sativa var. capitata, is susceptible to a number of economically important diseases, the most frequent being russet spot, rib discoloration, and vascular browning (28), which have been shown by Ceponis and Friedman (7) to be caused by Pseudomonas marginalis. Pseudomonads are common plant pathogens and cause such diseases as halo blight in beans (20), bacterial blight in soybeans (20), and bacterial wilt of the bird-of-paradise (27) and tobacco (24).

Plants that develop symptoms similar to russet of lettuce are oats, infected by Pseudomonas cichorii, and tobacco infected with Pseudomonas tobaci (34). In general, russet symptoms …

The Effect Of Two Growth Retardant Chemicals, Cycocel And B-Nine, On Certain Nitrogeneous Components In Barley Seedlings, Linda Kinser

Masters Theses & Specialist Projects

Certain chemicals are known to inhibit growth in many plant species. These chemicals possess a common trait, the ability to inhibit stem elongation by suppressing the activity of the subapical meristematic region (11). These growth retardants have been extensively studied during the past several years in an effort to determine the biochemical mechanism responsible for reduction in plant height. The characteristic effect of these chemical retardants on the growth pattern has been described as producing plants with shorter, thicker stems and broader, darker green leaves. Tolbert, however, noted that although plants treated with the plant growth retardant, Cycocel, (2-chloroethyltrimethlammoniumchloride) and …