Ciliopathies are a genetic disorder caused by defects in the structure and function of cilia. Cilia are hair-like structures that are found on the surface of almost all cells of a human and are important for the physiological processes. There are multiple genes associated with ciliopathies, including the bbs-5 gene. When this gene is mutated, it causes Bardet-Biedl Syndrome (BBS), a unique type of ciliopathy. This can be seen as retinal degeneration, cleft lip/palate, hepatic cysts, etc. There is still little known about how these phenotypes arise in individuals with BBS. The purpose of this research is to use Caenorhabditis elegans as a model organism to study BBS C. elegans with mutations in bbs-5 retain eggs instead of releasing them, but it is currently unknown why this occurs. Serotonin is a neurotransmitter in many organisms that plays a role in modulating behaviors, like the keeping and releasing of eggs. This experiment aims to identify the relationship between the bbs-5 gene and serotonin production and levels. To do this, we will use immunofluorescence to observe serotonin levels directly in bbs-5 mutant animals. We expect to see that bbs-5 mutant animals possess less serotonin than wild-type animals, leading to retention of eggs. This research will allow us to know more about the connection between serotonin and its effects on ciliopathy.

As microplastics continuously enter different water sources organisms have a hard time avoiding them and need strategies to protect themselves from their harmful effects. The main cellular-level concern of microplastics are their damaging effects on chromosomes and subsequent decreased cellular viability. Most organisms first react to microplastics by activating oxidative stress and antioxidant genes that are responsible for DNA repair and protection. The model organism Tetrahymena, a unicellular eukaryote, is a good model for studying cellular effects of microplastics because many of their genes are similar to those that are found in other eukaryotes like humans. Experimental methods included exposing cells to varying exposure times of polystyrene microplastic powder and assessing not only visual cellular changes and cell viability, but also the expression of ten genes hypothesized to be connected with stress responses. Five of these candidate genes are associated with oxidative stress responses, while the other five code for antioxidant proteins. Preliminary results suggest that Tetrahymena use antioxidant genes more than oxidative stress genes in response to microplastics. Applications of this research include hypothesizing ways that other organisms can protect themselves from microplastics, or identifying possible therapeutic enzymes that upkeep the protection of DNA for medical application.

Bacteriophages (phages) are viruses that infect bacteria. Phages are found anywhere bacteria can be found therefore they likely play important roles in diverse environments, including human health, biotechnology, and agriculture. Despite the vast number of phages, we know relatively little about them. In an effort to better understand phage genome organization and gene function, we are currently building a plasmid-based overexpression library of a complete set of genes for Mycobacteriophage Severus. Severus, a temperate cluster A10 siphovirus isolated on M. smegmatis mc2 155 (PhagesDB), encodes 80 genes. Fifty six percent of which have no known function. Each gene will be amplified using polymerase chain reaction and then cloned into the pExTra expression vector through isothermal assembly. To date, of the 80 Severus genes, twenty-eight have been successfully cloned into the expression vector. As we continue to build the complete genome overexpression library, we are working to characterize the function of each gene through phenotypic assays. Cytotoxicity assay will be used to identify phage genes that slow or inhibit hosts cell growth. We will also test whether expression of each severus gene functions to protect the bacterial host from infection by phages using a defense assay. We will present the design of our library construction and results of the phenotypic assays. This project is part of an ongoing collaboration with Howard Hughes Medical Institute through the Science Education Alliance’s Gene-function Elucidation by a Network of Emerging Scientist (SEA-GENES) program (SEA-PHAGES).