Show simple item record

dc.contributor.advisorNunez, B. Scotten
dc.creatorNoel, Megan L.en
dc.date.accessioned2016-01-08T22:34:31Zen
dc.date.available2016-01-08T22:34:31Zen
dc.date.issued2006-12en
dc.identifierdoi:10.15781/T2S922en
dc.identifier.urihttp://hdl.handle.net/2152/32789en
dc.descriptiontexten
dc.description.abstractThis study investigated the steroidogenic capacity of the Atlantic stingray (Dasyatis sabina) brain by examining the expression of steroidogenic genes in four sections of the brain (corpus cerebellum, telencephalon, tectum and medulla). Primer sequences specific for D. sabina steroidogenic factor-1 (SF-1), side chain cleavage (SCC), steroidogenic acute regulatory protein (StAR), 3[Greek letter Beta]-hydroxysteroid dehydrogenase (3[Greek letter Beta]-HSD) and 11[Greek letter Beta]-hydroxylase were used in RT-PCR to determine if their corresponding mRNAs are present in D. sabina medulla, corpus cerebellum, tectum and telencephalon, from unstressed and stressed adult stingrays (disc width [less than or equal to] 30 cm). Between both sexes and stress states, each of the genes investigated was present in at least one area of the brain, with usually more than one gene being present in a specific brain region. SCC, StAR and SF-1 were not as abundant as 11[Greek letter Beta]-hydroxylase, aromatase and 3[Greek letter Beta]-HSD, suggesting that rather than being capable of de novo synthesis, the D. sabina brain might be more involved in the activation of circulating steroids. Digital, semi-quantitative analysis of gene expression did not show statistically significant changes in gene expression with stress, or between the brain regions or sex. However, an interesting trend is seen in the males: males tended to produce less aromatase and more 11[Greek letter Beta]-hydroxylase when stressed, suggesting a switch from the production of estrogens to androgens under stress. This study suggests that the D. sabina brain is capable of steroidogenesis, and that stress may play an important role in regulating steroidogenic gene expression, though further work is needed to determine the types of neurosteroids produced.en
dc.format.mediumelectronicen
dc.language.isoengen
dc.relation.ispartofUT Electronic Theses and Dissertationsen
dc.rightsCopyright © is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en
dc.subjectAtlantic stingray(Dasyatis sabina)en
dc.subjectSteroidgenic genesen
dc.subjectNeurosteroidsen
dc.titleThe effect of stress on steroidogenic gene transcription in the Atlantic stingray (Dasyatis sabina) brainen
dc.typeThesisen
dc.description.departmentMarine Scienceen
dc.type.genreThesisen
thesis.degree.departmentMarine Scienceen
thesis.degree.disciplineMarine Scienceen
thesis.degree.grantorThe University of Texas at Austinen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Scienceen
dc.rights.restrictionRestricteden


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record