2021 Biological Sciences
The pre-recorded talks and posters on this page showcase the work of students who received NC Space Grant research funding for the 2019-20 and 2020-21 academic years. The menu at right provides links to pre-recorded talks and posters by other funded students on additional topics.
Melika Osareh
2020-2021 NC Space Grant Undergraduate Research Scholar
The University of North Carolina at Greensboro
Undergraduate Student (Junior), Biology
Analysis of Plant Gravitropism via Clinorotation Studies
Growing plants in space, on the Moon, or Mars, would enable prolonged space exploration by providing astronauts with fresh food, oxygen, and psychological benefits. However, growing plants in altered gravity conditions can be challenging because plants may suffer from gravitational stress. Our research project aimed to find natural genotypes of the plant Arabidopsis thaliana resistant to gravitational stress. To simulate gravitational stress, we used a clinostat, a device designed to randomize the gravity vector. To test each of the 133 wild-type genotypes of Arabidopsis thaliana, seedlings were rotated on a 2D-clinostat at 1.25-rpm or kept vertically, as a control, for seven days. Morphological parameters measured include: shoot length, main root length, number of secondary roots, total root length, and number of root hairs per total root length. For each genotype, these parameters were compared by t-tests in clinorotated seedlings and vertically-grown controls.
From the 53 genotypes analyzed, most genotypes under clinorotation showed significantly reduced shoot and root growth in comparison to the vertically-grown controls. However, genotypes Col-0 and CIBC-5, showed no difference or increased growth across all morphological parameters. We expect these genotypes may be better adapted for growth in microgravity conditions. Five genotypes also showed an increase in total root length and may be of interest for further study. Under clinorotation, 16 genotypes had similar or fewer number of root hairs per root length than controls which may indicate lower stress levels. Future plans include Genome Wide Association Studies and identification of genes that are involved in developing gravitational stress-resistance in plants. Potentially, these genes could be engineered to produce plant varieties that will grow well in microgravity or in reduced gravity environments. We gratefully acknowledge support provided by the NC Space Grant fellowship for M. Osareh in 2019.
Faculty Advisor: John Z. Kiss
Nicholas Syracuse
NASA Internship Award at Kennedy Space Center – Spring 2021
North Carolina State University
Undergraduate Student (Junior), Biochemistry and Biological Sciences
Developing a Sustainable, User-Friendly Literature Database to Support the Microgravity Simulation Support Facility (MSSF) at NASA’s Kennedy Space Center (KSC)
Established in 2017, the Microgravity Simulation Support Facility (MSSF) at NASA’s Kennedy Space Center is the only centralized, dedicated facility supporting ground microgravity research in the United States. The MSSF offers the research community the ability to conduct simulated microgravity research with experimental conditions functionally resembling those aboard the International Space Station (ISS) and in other flight-based experimental environments. Since its inception, the MSSF has supported numerous studies and has since collected an extensive library of relevant and pertinent literature. The goal of our research was to develop and implement a sustainable, user-friendly literature database to better house this literature at the MSSF. To achieve this, our team focused on sorting, optimizing, and analyzing preexisting literature libraries to determine a best suitable and sustainable platform for the MSSF. After establishing initial database platforms, the team worked to develop descriptive and structural metadata categories to best sort the literature, which was followed by rigorous testing and optimization of the database as it was implemented. The MSSF has now been outfitted with a reliable, accessible database that effectively houses literature and provides diverse analysis to the user. Our team is continuing to test and update our platform and parameters as we aim for the formal implementation, expansion, and evolution of our database to better sustain future research ventures at the MSSF and beyond.
Advisor: Anna Maria J. Ruby and Dr. Ye Zhang (NASA Kennedy Space Center)
Joseph Tolsma
2020-2021 NC Space Grant Graduate Research Fellow
North Carolina State University
Graduate Student (Ph.D.), Genetics
Influence of the Circadian Clock on the Arabidopsis Gravitropic Response
Circadian rhythms are regular oscillations of an organism’s physiology with a period of approximately 24 hours. In Arabidopsis, circadian rhythms regulate a suite of physiological processes, including transcription, photosynthesis, growth, and flowering. To characterize the circadian clock’s effects on the gravitropic response, we performed a root-bending assay over a 24-hour time course in diel and constant light conditions. We identified differences in the response angle, dependent on the time of reorientation. While the total root growth rate after 24 hours was similar for all time points, the root growth rate did vary throughout the day. Two time points, ZT12 and ZT22, with the most significant difference in response, were selected for further study. Importantly, root bending angle differences were identified in both diel and constant light conditions. We also identified circadian clock mutants that exhibited different gravitropic responses than wild type (WT) plants. Using the random positioning machine (RPM) at Kennedy Space Center, we compared the response of WT plants and plants with constitutive, high-level expression of CCA1 (a core component of the circadian clock). We grew seedlings under staggered lighting conditions so that when the plants were moved to the RPM, it would be near dawn for one set and dusk for the other. The plants were kept in simulated microgravity on the RPM for 48h. This allowed for a direct comparison of the two phases identified in the root bending assay as affecting the response angles. The RPM experiments revealed similar trends consistent with a differential response at the two time points. Our results suggest that the time of day and its relation to periods of differential root growth influence the plant responses to gravity.
Faculty Advisor: Colleen Doherty
Jared Tuton
2020-2021 NC Space Grant Undergraduate Research Scholar
The University of North Carolina at Pembroke
Undergraduate Student (Junior), Biology (Biomedical emphasis)
Evidence β1 integrin responses are involved in Seizure Vulnerability that Compromises Hippocampal Synapses
Long-term aerospace travel presents several potential stressors and high-risk health consequences to the brain and to synaptic integrity. Some of these potential stressors include traumatic brain injury (TBI), turbulence-induced mild TBI, lack of sleep, isolation, and hypoxia, all of which have been linked to increased susceptibility to seizures. The organophosphate paraoxon (PXN), an acetylcholinesterase inhibitor, exhibits seizure events associated with synaptotoxicity profile via cholinergic crisis, and perhaps the abnormal induction of adhesion responses such as β1-integrin, a synaptic adhesion receptor that regulates synaptic maintenance (Farizatto et al. 2017 J Mol Neurosci 63:115–122; Farizatto et al. 2019 Sci Rep. 9(1):6532). Here, the aim was to identify the β1 integrin dynamics on synaptic integrity in mature hippocampal tissue. Rat hippocampal slice cultures, a model that maintains the hippocampal native organization and circuitry, were treated with 200 μM organophosphate PXN for 24 hours with or without Bio5192, a β1 integrin inhibitor. Following, synaptic proteins and an active form of β 1 integrin were assessed by immunoblot. The hippocampal explants exposed to PXN exhibited a progressive decline in the synaptic markers synaptophysin and synapsin IIa & IIb with correspondent increase in the active β1 integrin adhesion protein. Interestingly, the synaptic compromise in PXN exposed explants was reduced by the application of the inhibitor Bio5192, hence blocking β1 integrin signaling provided synaptic protection. The implication of this study is the therapeutic role of negative integrin modulation for preserving synaptic integrity. However, more data is needed to understand the specific relationship between synaptoxic events and induced adhesion responses.
Faculty Advisor: Ben Bahr