BIOLOGY

Gene Expression of Par-1 in Cancer Cells in the Presence of Thrombin

Presenter: Kaitlyn Moss

Faculty Advisor: Marc Lockett

Proteinase-activated receptor-1 (PAR-1) not only regulates platelet function but has a role in the development of multiple cancers. PAR-1 is activated by thrombin, which is the key enzyme of blood coagulation and when overproduced, can promote tumor growth. This project explores the importance of the PAR-1 activation in response to varying concentrations of thrombin using the cancer cell line CCF- STTG1. To investigate this response, three different concentrations of thrombin were used: 2.5 units, 5 units, and 10 units. Results showed that the higher concentration of thrombin, the higher cell count of CCF-STTG1. A PAR-1 antagonist was then used to confirm if thrombin activity could be inhibited to decrease the activation of CCF-STTG1 cells. Finally, to determine downstream effects of PAR-1 activation, a RT-PCR was performed (results pending).

Observing the Differences in Mammal Species Across Suburban and Rural Wooded Areas Using Camera Traps

Presenter: Charisse Walker

Faculty Advisor: Andy Madison

My research objective was to observe mammal species’ differences across suburban and rural wooded areas using trail camera traps. I assumed that rural areas would have higher species richness and abundance. Camera traps were placed from 2 January - 30 July, 2022 and all mammals observed were documented. Two sites in Chattanooga, a site in Jackson, and a site in McKenzie, TN, were used for observations. Two different statistical analyses were used to compare data from the different sites. Tentative data for the Chattanooga sites show the suburban site has higher richness and abundance than the rural site, contrary to my hypothesis. This could be random chance (only one site was chosen) or because the mammals were concentrated into the only available habitat. Chattanooga is more industrialized and larger than Jackson, so that could also be a factor in the final results.

Myotis septentrionalis and Myotis sodalist Habitat Suitability Model Analysis Using ArcGIS on a Wetland Mitigation Site in West Tennessee

Presenter: Emma Straley

Faculty Advisor: Michael Schiebout

The Rossville Farm Mitigation Site, near Memphis, TN, was acoustically surveyed for 2 federally protected Myotis species, Myotis septentrionalis (northern long-ear bat) and Myotis sodalis (Indiana bat). Bat presence can be an indicator of habitat health. Because both Myotis species utilize the same feeding grounds and there is indication the Mitigation Site might harbor them, we used ArcGIS to create a habitat suitability model for the 2 bat species. Bat calls were recorded with Wildlife Acoustics Echo Meter Touch Pro. The recordings were analyzed using Wildlife Acoustics’ Kaleidoscope software and analyzed. Three bat species were detected, although not our target species. The presence of these other bats suggests the reclamation plan being implemented for the Rossville Farm Mitigation Bank is successfully establishing functional wildlife habitats.

Six in One: Cryptic Species and a New Host Record for Olixon testaceum (Vespoidea: Rhopalosomatidae) Revealed by DNA Barcoding

Presenter: Allaina Armstrong

Faculty Advisor: Jeremy Blaschke

New discoveries have increased our knowledge of the systematics and behavior of Olixon Cameron, an understudied genus of parasitoid cricket-assassin wasps (Vespoidea: Rhopalosomatidae). Little is known about the biology of these brachypterous wasps. Olixon testaceum is one of the most widespread of rhopalosomatid species, occurring in Central and South America. The widespread distribution and habitat variation of O. testaceum makes it an excellent candidate for genetic species delimitation study using data from the Barcode of Life Database (BOLD). Here we report Anaxipha cf. calusa as the first confirmed host of O. testaceum, as well as genetic evidence of 6 cryptic species within the nominal species O. testaceum

Comparison of Cold and Room Temperature Plastination

Presenter: Lauren Gaggley

Faculty Advisor: Micah Fern

The use of plastinated specimens for anatomical studies is a growing field. Plastination is a method of preservation that replaces water in living tissues with plastic polymers. The current standard for this method of preservation is cold temperature plastination, but specimen shrinkage, equipment cost, and long procedure duration have been problematic. Room temperature plastination is an alternative method to the standard cold temperature plastination. Cat (Felis catus) and pig (Sus scrofa domesticus) brains were plastinated using cold temperature (CT) and room temperature (RT) plastination methods effect on specimen shrinkage. Criteria used to measure all plastinates included mass, length, width, and height. Equipment dependance, length of processes and costs were also calculated for CT and RT plastination methods. Results of this study are pending.

Downstream Effects of Thrombin-Induced Par-1 Activation in Fibroblast Cells

Presenter: Sydney Sample

Faculty Advisor: Marc Lockett

Clotting factors regulate several processes during wound healing, with angiogenesis, new blood vessel formation, being crucial. In addition, fibroblasts and endothelial cells mediate physiological functions of angiogenesis. The clotting factor, thrombin, has been implicated in mediating angiogenesis in endothelial cells. However, the effect of thrombin on fibroblast function is less well characterized. This research is being conducted to examine if thrombin mediates angiogenesis in fibroblast cells through proteaseactivated receptor-1 (PAR-1) activation. It was hypothesized that thrombin will induce angiogenesis through PAR-1. This was determined by culturing 3T3-L1 fibroblast cells in varying conditions: control group, thrombin, PAR-1 agonist, and PAR-1 antagonist with thrombin. Cell cultures were performed for various time periods to examine the time frame in which thrombin and PAR-1 mediate gene expression. RT-qPCR was then used to analyze expression of angiogenesis genes, cathepsin-S and vascular endothelial growth factor (results pending).