Honours Project Book - Faculty of Health Sciences - University of ...

PROJECT: (Basic) Stem Cells of Ovarian Follicles.
R. O&G.
Supervisors
Professor Ray Rodgers
Project Background
Our laboratory has shown that a proportion of
granulosa cells isolated directly from antral follicles
have a number of stem cell properties. These include
the ability to divide under anchorage independent
conditions [2], divide without contact inhibition [1]
and express telomerase [3]. On this basis we
proposed the model shown in the above figure [1].
It assumes plutipotentiality into at least cumulus cells
(specialized cells surrounding the oocyte) and mural
granulosa cells. The pluripotency of granulosa stem
cells has yet to be demonstrated, however in mice
expressing a dominant-stable mutant of betacatenin,
clonally derived granulosa cell tumours
develop. These can be of granulosa, bone or neural
phenotype [4], suggesting that tumours of granulosa
cells are pluripoten. The goals of this project are to
investigate the pluripotential of granulosa cells.
PROJECT: (Basic) Thecal stem cells – Real or not?
R. O&G.
Supervisors
Professor Ray Rodgers
Project Background
In a recent Proceedings of the National Academy of
Sciences article, ‘thecal stem cells’ [5] were reported
in new born mice. However in this species follicles
are still developing at birth.
Whole ovaries were treated with collagenase and
from this a heterogeneous mixture of cells was
cultured and colonies of stem cells were identified in
anchorage-independent culture. The authors
identified expression of markers found in thecal cells,
which in vivo are only expressed in the presence of
granulosa cells. However they did not examine the
colonies to see if all cells expressed the markers.
Therefore it is possible that the colonies were of mixed
cell type, containing granulosa stem cells and some
thecal cells. Certainly the colonies bore a sticking
resemblance to granulosa stem cells [2].
References
Rodgers RJ, Lavranos TC, van Wezel IL, Irving-Rodgers
HF. Development of the ovarian follicular epithelium.
Mol Cell Endocrinol 1999; 151: 171-179.
Lavranos TC, Rodgers HF, Bertoncello I, Rodgers RJ.
Anchorage-independent culture of bovine granulosa
cells: the effects of basic fibroblast growth factor and
dibutyryl cAMP on cell division and differentiation.
Exp Cell Res 1994; 211: 245-251.
Lavranos TC, Mathis JM, Latham SE, Kalionis B, Shay
JW, Rodgers RJ. Evidence for ovarian granulosa stem
cells: telomerase activity and localization of the
telomerase ribonucleic acid component in bovine
ovarian follicles. Biol Reprod 1999; 61: 358-366.
Boerboom D, White LD, Dalle S, Courty J, Richards JS.
Dominant-stable beta-catenin expression causes cell
fate alterations and Wnt signaling antagonist
expression in a murine granulosa cell tumor model.
Cancer Res 2006; 66: 1964-1973.
Honda A, Hirose M, Hara K, Matoba S, Inoue K, Miki H,
Hiura H, Kanatsu-Shinohara M, Kanai Y, Kono T,
Shinohara T, Ogura A. Isolation, characterization, and
in vitro and in vivo differentiation of putative thecal
stem cells. Proc Natl Acad Sci U S A 2007; 104: 12389-
12394.
PROJECT: (Basic) Bioinformatics of Ovarian Follicle
Development.
R. O&G.
Supervisor
Professor Ray Rodgers
Bioinformatics is a newly emerging area of increasing
importance in all areas of biology. Currently there
are insufficient numbers of bioinformaticians to satisfy
the need to fully exploit the explosion of data
currently available, much less that to be produced in
the future.
Microarrays produce a wealth of data. We have
conducted over 70 Affymetrix gene expression arrays
each with over 20,000 probe sets which equates over
1.5 million pieces of data from our experiments alone.
We have arrays performed on RNA isolated different
ovarian compartments (theca layers, granulosa cells,
cumulus-oocyte complexes) from follicles at different
stages of health and development, and from cells
(theca and granulosa) in culture. There are
numerous computer programs for basic analyses and
we routinely use Partek and Ingenuity Pathway
Analysis (IPA) and are currently conducting basic
analysis of these arrays. We have made novel
discoveries of follicle development, not hitherto
apparent by previous hypothesis-driven research.
Heat Map of gene expression comparing 14 follicles.
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