Changes in Gene Expression During Bovine Granulosa Cell Luteinization

Rajapaksha, Welhena Rajapaksha Appuhamilage Kosala Jagath Sanjaya (1998) Changes in Gene Expression During Bovine Granulosa Cell Luteinization. PhD thesis, University of Glasgow.

Abstract

The corpus luteum develops from the remnants of the ovulatory follicle and rapidly becomes, for a short time, the most active of the steroidogenic tissues. Both the granulosa and thecal cells of the follicle differentiate into luteal cells although it is likely that they show different activities within the corpus luteum. Studies described in this thesis were designed to examine some of the changes which take place in the luteinizing granulosa cells using both corpora lutea of known ages land by following changes in cell activity following luteinization in culture. In particular, changes in expression of two cell-surface receptors, the follicle-stimulating hormone (FSH) receptor and the putative high density lipoprotein (HDL) receptor SR-BI. The first studies were designed to characterise changes in granulosa cells during luteinization in culture and to compare to changes in vivo during normal luteal development. Investigation of culture conditions showed that it was necessary to serum-treat culture dishes to iobtain cell-attachment. Comparison of serum-containing and serum-free culture medium showed that granulosa cell number, progesterone production and cytochrome P450 side chain cleavage (P450scc) activity only increased markedly in the absence of serum. Levels of mRNA encoding P450scc increased in culture and in vivo during luteinization while levels of cytochrome P450 aromatase decreased markedly at the same time. There was little change in levels of the transcription factor SF-1. These studies showed that changes in vitro were similar to changes in ivo. It is uncertain whether bovine granulosa cells retain FSH-receptors after luteinization and whether there is a change in receptor splicing at this time. Using reverse-transcription and the polymerase chain reaction (RT-PCR) and Southern blotting expression of the FSH-receptor was measured in granulosa cells before and after luteinization in vivo and in vitro. Before luteinization full-length transcripts and two major alternate transcripts were observed. The alternate transcripts lacked exons 4 and 5 or exon 9. After luteinization in vitro or in vivo no full-length receptor transcripts were detected but shortened transcripts, lacking the transmembrane domain of the.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: P J O'Shaughnessy
• Keywords: Veterinary science, Animal sciences
• Date of Award: 1998
• Depositing User: Enlighten Team
• Unique ID: glathesis:1998-75944
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 17:14
• Last Modified: 19 Nov 2019 17:14
• URI: https://theses.gla.ac.uk/id/eprint/75944