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The Pleiotropic Effects Of Beneficial Mutations Of Adapted Escherichia Coli Populations, Brian Scott Van Dam
The Pleiotropic Effects Of Beneficial Mutations Of Adapted Escherichia Coli Populations, Brian Scott Van Dam
Honors Theses and Capstones
Mutations that improve fitness in one environment can often be beneficial, deleterious, or neutral in alternative environments. When a single mutation effects fitness in multiple environments, it is said to be a pleiotropic, which can have important consequences for niche specialization, niche expansion, speciation, and even extinction in the face of environmental change. While previous studies have revealed that pleiotropy is nearly universal, the role of adaptive history in the spectrum of pleiotropic effects has yet to undergo detailed experimental observation. Using experimental evolution we gathered beneficial mutations in a previously adapted strain of Escherichia coli growing in the same …
The Distribution Of Fitness Effects Of Spontaneous Mutations In Vibrio Fischeri, Chelsea K. Jones
The Distribution Of Fitness Effects Of Spontaneous Mutations In Vibrio Fischeri, Chelsea K. Jones
Honors Theses and Capstones
Mutations are the ultimate source of the biological diversity on which natural selection acts, but the vast majority of these mutations are harmful. As such, mutations lead to disease states like cancer, extinction of small populations, and can drive pathogen evolution. Unfortunately, because mutations are rare and past studies have been subject to detection biases, very little is known about the distribution of fitness effects from naturally occurring mutations. In this study, we used mutation accumulation and full genome sequencing to capture naturally occurring mutations before they were exposed to the sieve of natural selection in Vibrio fischeri. We …
Investigating The Interactions Between Cyanobacteria And Vibrio Parahaemolyticus, Caroline E. Ward
Investigating The Interactions Between Cyanobacteria And Vibrio Parahaemolyticus, Caroline E. Ward
Honors Theses and Capstones
One well-known pathogen that has been the topic of many recent studies is Vibrio parahaemolyticus, which causes thousands of foodborne illnesses a year, mostly from the ingestion of raw or undercooked oysters. It has been shown cyanobacteria can act as a long-term reservoir of Vibrio cholerae, another pathogenic Vibrio, by encasing the cells within mucilaginous sheaths during which Vibrios enter a viable but non-culturable state. In this study we investigated the interaction of V. parahaemolyticus with cyanobacteria to determine whether cyanobacteria aid in the longevity and survival of V. parahaemolyticus. We found that non-pathogenic V. parahaemolyticus …
One Can’T Stand On Its Own: Are Non-Luminescence Traits Necessary For V. Fischeri Colonization Of E. Scolopes?, Feier Liu
Honors Theses and Capstones
Vibrio fischeri and Euprymna scolopes squid establish mutualistic symbiosis and select for each other in the natural environment. V. fischeri provides bioluminescent camouflage for E. scolopes while E. scolopes provides nutrients for V. fischeri. The most intriguing aspect of this relationship is that E. scolopes is highly selective and only allows sustained colonization by luminous, but not dark V. fischeri. Luminescence is the key symbiosis trait; however, other bacterial factors may also allow squid recognition. We hypothesized that there are luminescence linked traits that contribute to colonization. V. fischeri with luminescence variation was isolated and tested for oxidative resistance, …
The Effects Of Cytokinin On The Transcriptional Regulation Of Pin Expression In Arabidopsis Thaliana, Elizabeth Burgess
The Effects Of Cytokinin On The Transcriptional Regulation Of Pin Expression In Arabidopsis Thaliana, Elizabeth Burgess
Honors Theses and Capstones
The processes of cell division and differentiation are critical to the development of any multicellular organism. During the formation of plant roots these processes take place at a region of the root tip called the meristem. Cytokinin and auxin are two plant growth hormones that influence this process. Although these two growth hormones are both necessary they also appear in many ways to have an antagonistic relationship. As meristematic root cells undergo differentiation they cease dividing. It has been proposed that the size of the root meristem and thus the overall rate of root growth are determined by the balance …
Replication Protein A (Rpa70c) Negatively Regulates Ribonucleotide Reductase (Rnr) In The Model Plant Arabidopsis Thaliana, Stacy Wong
Honors Theses and Capstones
Replication protein A (RPA) is a heterotrimeric single-stranded DNA-binding protein that plays an important role in cellular responses to DNA damage. For example, RPA can activate the cell-cycle checkpoint protein ATR in the presence of persisting DNA damage. The model plant Arabidopsis thaliana has 5 functional homologous RPA70 genes which may play specific roles in response to DNA damaging agents. One chemical that causes DNA damage in Arabidopsis is Hydroxyurea (HU), which blocks DNA replication by inhibiting activity in Ribonucleotide Reductase (RNR), an enzyme responsible for the production of free deoxyribonucleotides (dNTPs). In studies of Arabidopsis mutants, atr plants, but …
Transformation Of Tobacco With The Ba5 Cement Protein Gene From Balanus Amphitrite, Matt Marquis
Transformation Of Tobacco With The Ba5 Cement Protein Gene From Balanus Amphitrite, Matt Marquis
Honors Theses and Capstones
Expressing barnacle cement proteins genes such as the BA5 gene in plants may enable individual study and analysis. This technique is effective since barnacle cement is difficult to work with as a whole in the lab setting. The BA5 gene extracted from Balanus amphitrite is transferred to tobacco leaf tissue using Agrobacterium tumefaciens.