archives@tulane.edu / In this dissertation, I characterize the origins, phylogenetic distribution, and function of Follicle Cell Processes (FCP) in Class Chondrichthyes. FCP are actin associated tubes that have been detected in the intercellular space between a developing oocyte and the surrounding follicle cells in chondrichthyan fishes. Using light microscopy, I describe the presence FCP in Hydrolagus colliei, a species of Subclass Holocephali, a divergent lineage at the base of the chondrichthyan phylogeny. FCP were also detected in species representing six of nine studied orders of Subclass Elasmobranchii, the sister group of holocephalans, but absent in three examined batoid orders. To establish the role FCP play in vitellogenesis - the process of providing yolk to developing oocytes - I performed fluorescent microscopy, staining specifically for myosin, an actin-associated transport protein previously identified in vitellogenic oocytes. The detection of myosin in oocytes during vitellogenesis and its association with actin in FCP are inconclusive. I performed RNA sequencing on follicles and ovarian tissues from Mustelus sinusmexicanis, using Illumina Hi-Seq 4000 profiling with the specific aim of identifying the types of myosins and actins involved in yolk transport. Three (MYH9, MYH10, and MYO5A) of particular interest and one actin (ACTG1L) were differentially expressed in the tissues. MYO5A is a class V myosin that has been associated with cytoplasmic vesicle transport, though it is most abundant in melanocytes and nerve cells. MYH9 and MYH10 are membrane associated non-muscle class II myosin paralogs, and MYH9 was upregulated in the ovarian tissues; MYH10 was upregulated in the corresponding follicle tissues. ACTG1L, the only actin transcript differentially expressed codes for a gamma actin isoform involved in internal cell mobility. / 1 / Lydia Crawford
| Identifer | oai:union.ndltd.org:TULANE/oai:http://digitallibrary.tulane.edu/:tulane_120438 |
| Date | January 2020 |
| Contributors | Crawford, Lydia (author), Bart, Henry Jr. (Thesis advisor), School of Science & Engineering Ecology and Evolutionary Biology (Degree granting institution), NULL (Degree granting institution) |
| Publisher | Tulane University |
| Source Sets | Tulane University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | electronic, pages: 100 |
| Rights | No embargo, Copyright is in accordance with U.S. Copyright law. |
Page generated in 0.0022 seconds