Major
Biological Sciences
Date
5-2015
Abstract
Diplosoma listerianum is an invasive tunicate species that can reproduce asexually by pyloric budding. Tunicates, more commonly known as “sea squirts” or ascidians, are filter feeding marine invertebrates. Pyloric budding is a unique form of asexual reproduction among tunicate species in which the esophagus of a single animal will form two buds, each of which develops into parts of a new genetically identical animal. The overall goal of my research is to better understand the genes that are important for this organism’s asexual development. More specifically, this project examines the role of the SOX2 gene in Diplosoma, to find out whether this gene is expressed in the budding tissue of the organism using a method known as in situ hybridization, which uses a labeled complementary RNA strand to see where a specific gene sequence is being expressed in a fixed tissue sample. I know from my own past research that the SOX2 gene is expressed in Diplosoma, but the role it plays in this organism has not been previously studied. In humans, SOX2 is an important transcription factor in embryonic stem cells that is essential for stem cell pluripotency, which is the ability of stem cells to differentiate into specific tissue types. Our hypothesis is that the asexual buds develop from stem cells, and that Sox2 will be expressed in those cells. Thus, researching the role that SOX2 plays in Diplosoma could have implications for stem cell research and regenerative medicine in humans. From past research, I have extracted Diplosoma RNA and used this to make cDNA. I was then able to successfully make many copies of the SOX2 fragment through PCR, and determined the exact sequence of the gene in Diplosoma. For this project, I ligated the SOX2 gene into the puc18 plasmid vector, and sequenced it. This can be used to create the labeled RNA probe for the in situ, enabling future research to be done to conclusively determine where SOX2 gene expression occurs in Diplosoma.