The Role Of GRHL-3, A Mammalian Homologue Of Drosophila Grainyhead, In Neural Tube Development
Funder
National Health and Medical Research Council
Funding Amount
$496,500.00
Summary
Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first ....Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first few hours of life. These abnormalities occur frequently (1-1000 live births) and are a direct result of failure of the neural tube to close during embryogenesis. NTDs are influenced by both environmental and genetic factors. The best characterised environmental factor is the dietary supplement folate, which when administered before conception results in a reduction in the incidence of spina bifida. The genetic complexity is evidenced by the array of mouse genetic mutations that give rise to NTDs. One of these mouse mutations, known as Curly tail (ct), has served as the major animal model of human NTDs. This is because the ct mice are resistant to folate administration (like most of the cases of spina bifida currently seen in patients) and because the mice seem to have normal development in virtually all other organ systems. Ironically, the genetic mutation that causes the curly tail phenotype has remained undiscovered for over 50 years. We have now identified the gene mutated in the curly tail mice. This gene is highly conserved in humans suggesting that it will play a similar role in neural tube development in man. The gene, known as GRHL-3, is a descendant of a fly gene critical for development of the nervous system in that organism. The studies we propose here will examine the developmental pathways involved in normal neural tube closure in mice and humans and will impact on our understanding of these devastating congenital malformations.Read moreRead less
LIM KINASE 1 (LIMK1) AND METASTASIS, THE SEARCH FOR LIMK1 INHIBITORS
Funder
National Health and Medical Research Council
Funding Amount
$461,250.00
Summary
Disseminated cancer, unlike the localized disease, can rarely be cured by drug therapy. We have found that LIM kinase (LIMK1), a protein that was discovered in our laboratory, plays an important role in controlling the ability of tumour cells to spread, a process called metastasis. Thus, this protein becomes an important target for the development of new drug therapies to prevent the spread of cancer. Importantly, we have demonstrated that (1) inhibiting LIMK1 blocks the formation of metastatic ....Disseminated cancer, unlike the localized disease, can rarely be cured by drug therapy. We have found that LIM kinase (LIMK1), a protein that was discovered in our laboratory, plays an important role in controlling the ability of tumour cells to spread, a process called metastasis. Thus, this protein becomes an important target for the development of new drug therapies to prevent the spread of cancer. Importantly, we have demonstrated that (1) inhibiting LIMK1 blocks the formation of metastatic tumours in mice, and (2) introduction of this protein into tumour cells makes them more invasive. In addition, we find that the level of LIMK1 is much higher in human tumour cell lines that have the propensity to easily form tumours in mice. Also, measuring the level of this protein in cancer cells that spread to other organs shows that it is at significantly elevated levels when compared to normal tissue. The goals of this research are to: (1) understand whether the ability of LIMK1 to regulate tumour spreading and invasiveness correlates with its ability to control metastasis; (2) examine in human tumour samples whether the levels of LIMK1 correlate with the development of metastatic tumours; and (3) search for drugs that can inhibit the activity of this protein. The results from this research will be highly significant because LIMK1 levels are likely to be an important marker for which tumours will become metastatic. It is possible that, at the time of tumour diagnosis, LIMK1 measurements will enable the clinician to predict whether an individual tumour will become metastatic. Secondly, this protein is a novel drug development target. Drugs that inhibit this protein may block the ability of tumours to invade and metastasise.Read moreRead less
Relaxin-3 Systems In Brain: Validation Of Neural Targets And Functional Roles
Funder
National Health and Medical Research Council
Funding Amount
$537,579.00
Summary
Our laboratory recently discovered the brain 'transmitter' called 'relaxin-3', and are researching how it affects brain activity and animal physiology and behaviour. Findings suggest that relaxin-3 can modulate memory, responses to stress and other complex behaviours. Identifying the various actions of relaxin-3 in the brain could provide potential new treatments for conditions such as anxiety-depression, cognitive deficits (dementia) and schizophrenia.