6% of Australian men are infertile. Of these cases 50% are thought to be genetic in origin. Within this project we will replicate high-confidence genetic variants associated with human male infertility in the mouse. Doing so will allow the assignment of definitive genotype-phenotype correlations and the formulation of high confidence advice for clinicians and patients. It will also provide a means to define the mechanism of action and the tools for future pro-fertility treatments.
Role Of Snail Family Proteins In Male Fertility And Testicular Cancer
Funder
National Health and Medical Research Council
Funding Amount
$586,076.00
Summary
Male fertility requires production of healthy sperm in the testis. This project builds on our discoveries that testicular cells regulate gene activity via the Snail family of proteins during sperm development, and that interruption of their activities reduces fertility in mice and fruitflies. Snail proteins are also active in cancer cells. We propose to study the precise steps in sperm production affected by Snail proteins and how they affect the progression of testicular cancer.
An inability to control human fertility is an issue of global significance. Frequently both unwanted pregnancies and infertility result from the same origin, a lack of understanding of how germ cells are produced. Within this fellowship I will define key processes involved in the manifestation of male fertility. Further I will extend these insights into both the fertility clinic but also into human health more broadly.
This project aims to study the hormonal control of Sertoli cell development and function. In the testis, these highly specialised cells provide essential nutritional and structural support for sperm production. In current NHMRC-supported research we created a unique mouse model to study the individual roles of two key reproductive hormones FSH and testosterone in spermatogenesis. This novel approach involved the selective expression of transgenic FSH on the hormone-deficient background of hpg mi ....This project aims to study the hormonal control of Sertoli cell development and function. In the testis, these highly specialised cells provide essential nutritional and structural support for sperm production. In current NHMRC-supported research we created a unique mouse model to study the individual roles of two key reproductive hormones FSH and testosterone in spermatogenesis. This novel approach involved the selective expression of transgenic FSH on the hormone-deficient background of hpg mice, which normally lack both androgens and FSH. Our analysis revealed that FSH provided the main stimulation for Sertoli cell and early germ cell proliferation, whereas FSH required testosterone for later stages of sperm formation. In this proposal we now plan to investigate FSH and the changing steroidal contributions during the critical postnatal stage of Sertoli cell development. We will study individual of combined actions of FSH and steroids, including the controversial role of estradiol in Sertoli and germ cell function, which may all have profound consequences on sperm production and male fertility. We will also establish unique mouse models to address fundamental questions about the mechanisms of androgen actions in the testis, and the requirement for androgen receptor expression in Sertoli and neighbouring peritubular cells for the overall testosterone response. Furthermore, we will use new microarray gene screening technology to identify the FSH- and androgen-regulated gene pathways during Sertoli cell proliferation. This research has relevance to the controversial view of environmental steroids affecting human testicular development and reducing sperm counts, and offers the potential to uncover new causes of previously unexplained male infertility or testicular cancers, and to help develop better strategies for hormonal male contraceptives, and treatments for male infertitliy or cancer.Read moreRead less
Hormonal Control Of Serotli Cell Maturation And Function
Funder
National Health and Medical Research Council
Funding Amount
$512,898.00
Summary
This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR ac ....This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR activity within Sertoli cells is essential for 'induction' of complete sperm development. Ongoing work will develop unique 'inducible' transgenic models that will allow, for the first time, selective analysis of Sertoli AR in both 'developing' and 'adult' testes. Our innovative models will allow AR function to be switched on or off at any stage of development, providing unique opportunity to determine the key AR-regulated factors and pathways controlling induction, maintenance or restoration of sperm production. In past NHMRC research we created a novel transgenic model to study another major reproductive hormone, FSH. Using the hormone-deficient background of 'hpg' mice, we found that androgen and FSH act synergistically in the developing 'meiotic' germ cells that form sperm. Using the latest microarray gene technology we generated datasets of androgen-regulated genes with or without FSH activity, which combined with our unique transgenic AR and FSH models, will be used to identify key pathways, including those enhanced by androgen-FSH synergism, in the early testicular response. Our research will provide new knowledge of the precise roles and pathways of testicular AR actions, to ultimately identify key genetic and regulatory factors as targets for significantly improved therapy for male infertility, gonadal tumours, or contraception.Read moreRead less
The Sertoli Cell: Master Regulator Of Hormone-induced Spermatogenic Development
Funder
National Health and Medical Research Council
Funding Amount
$563,536.00
Summary
This project will determine the key roles of major hormones (testosterone, follicle-stimulating hormone, Vitamin A) in Sertoli cells, unique highly specialised cells found in the testis that provide essential nutritional and structural support for sperm production. This research will provide new understanding of the biological pathways controlling sperm development, leading to new molecular targets for infertility or cancer treatment or diagnosis, or new contraceptive strategies for men.
Interstitially Invasive Trophoblast Of The Murine Placenta: Developmental Origins, Functions And Gene Expression.
Funder
National Health and Medical Research Council
Funding Amount
$369,717.00
Summary
Due to the obvious limitations to studying human pregnancy, the mouse has become a valuable model. However, invasion of the placenta into the uterine wall and vasculature, critical for successful pregnancy, is poorly understood in the mouse. The aims of the proposal are designed to gain a better understanding of these processes in mice and will provide a more accurate model system to study serious pregnancy complications resulting from abnormal placental invasion, such as preeclampsia.
The Identification Of Male Meiosis Genes Using A New Mouse Line And Human Genome Scans For Gene Copy Number Variations
Funder
National Health and Medical Research Council
Funding Amount
$604,793.00
Summary
Infertility affects 1 in 25 Australian men and meiosis is a key process in male fertility, yet we know very little about the mechanisms that control it. We will use a new point mutant mouse model of meisois failure to identify a novel regulator of male fertility. Further, we hypothesize that changes in gene copy number will lead to meiosis arrest and infertility in some men. Such variations will be assessed through a whole genome scan of a unique set of infertile men.