A Novel Gene Family Implicated In Neural Crest And Craniofacial Malformation
Funder
National Health and Medical Research Council
Funding Amount
$695,016.00
Summary
We have identified a new type of receptor that when defective causes facial clefting in animal models. We are using our unique laboratory and clinical resources to understand how these birth defects occur and to investigate the molecular signalling events that are controlled by this olfactory receptor. These studies will pave the way to designing pharmaceuticals that may eventually ameliorate or even stop this major group of birth defects.
Neogenin: A Molecular Determinant Of Neural Progenitor Polarity And Function
Funder
National Health and Medical Research Council
Funding Amount
$569,296.00
Summary
The neuroepithelium (NEP) contains the embryonic neural stem cells essential for the production of all neurons in the adult brain. Failure in NEP function leads to devastating neural tube defects and syndromes such as epilepsy, schizophrenia, and mental retardation. This project will identify the molecular mechanisms regulating NEP stem cell activity and the birth of new neurons in the embryonic neocortex.
The Role Of The Mammalian Grainyhead-like Gene Family In Neural Tube Closure
Funder
National Health and Medical Research Council
Funding Amount
$635,547.00
Summary
Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Our laboratories have identified a family of genes essential for the closure of the neural tube in mammals. The aim of this proposal is to understand the mechanisms of action of these genes with a v ....Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Our laboratories have identified a family of genes essential for the closure of the neural tube in mammals. The aim of this proposal is to understand the mechanisms of action of these genes with a view to developing new preventative therapeutics.Read moreRead less
Defects In Epidermal Morphogenesis In Mammalian Grainyhead-like Gene Deficient Mice
Funder
National Health and Medical Research Council
Funding Amount
$623,065.00
Summary
The cells of the skin play an essential role in development of the mammalian embryo. They are critical for closure of the brain and spinal cord, for forming a protective barrier against infection and noxious stimuli, for preventing excess fluid loss, for repair of defects and wounds, and for the generation of hair. Our laboratory has identified a family of genes that are critical for all these processes. Loss of individual members of the family has different consequences and the aim of this stud ....The cells of the skin play an essential role in development of the mammalian embryo. They are critical for closure of the brain and spinal cord, for forming a protective barrier against infection and noxious stimuli, for preventing excess fluid loss, for repair of defects and wounds, and for the generation of hair. Our laboratory has identified a family of genes that are critical for all these processes. Loss of individual members of the family has different consequences and the aim of this study is to determine the relationship between the genes to further our understanding of the skin and its functions. These studies have direct and important relevance to human conditions such as the congenital birth defects spina bifida and anencephaly, and infant prematurity where the skin is underdeveloped and lacks barrier function. They also have relevance to wound healing and to conditions in which hair growth is affected, such as alopecia. We believe that therapeutic interventions and prenatal diagnostic tests could evolve from these studies.Read moreRead less
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
Dissecting The Molecular Mechanisms Driving Cell Migration During Neurulation Triggered By The Netrin Receptor, Neogenin
Funder
National Health and Medical Research Council
Funding Amount
$432,750.00
Summary
In humans, abnormalities in brain and spinal cord formation during early embryogenesis result in congenital syndromes such as spina bifida and anencephaly. These defects occur at a rate of 1-1000 pregnancies and are therefore a major contributor to pre- and perinatal deaths. In the early embryo, the brain and spinal cord begin as a hollow tube of cells (the neural tube) that subsequently expands into the complex structures seen at birth. It is known that the neural tube is formed by a complex pr ....In humans, abnormalities in brain and spinal cord formation during early embryogenesis result in congenital syndromes such as spina bifida and anencephaly. These defects occur at a rate of 1-1000 pregnancies and are therefore a major contributor to pre- and perinatal deaths. In the early embryo, the brain and spinal cord begin as a hollow tube of cells (the neural tube) that subsequently expands into the complex structures seen at birth. It is known that the neural tube is formed by a complex process in which early neural cells migrate toward the midline of the embryo and subsequently coalesce. This project seeks to determine the function of one molecular signaling pathway (the neogenin pathway) that has been implicated in driving these cell migration events. We will initially use the frog, Xenopus laevis, as our embryonic model since the developmental processes that form the Xenopus neural tube closely parallel those ocurring in the human embryo. This model will allow us to identify the molecules in the neogenin signaling pathway. We will also create mice that carry a mutation in the neogenin gene so that we can study neogenin function in the mammal. We anticipate that these studies will provide important insights into the development of the central nervous system and also into the aberrant molecular processes underlying neural tube defects in man.Read moreRead less
Role Of Chromatin Structure In The Regulation Of Stem Cell Function
Funder
National Health and Medical Research Council
Funding Amount
$272,036.00
Summary
The aim of this project is to understand more about the nature of stem cells. Stem cells are cells which have the capacity to proliferate indefinitely but, at the same time, retain the capacity to differentiate into one or more cell types. Lower animals, such as amphibians, have a much greater capacity than humans to regenerate body parts. For example, axolotls can regenerate an entire limb if one limb is injured. This is because they retain undifferentiated stem cells in their limbs which can b ....The aim of this project is to understand more about the nature of stem cells. Stem cells are cells which have the capacity to proliferate indefinitely but, at the same time, retain the capacity to differentiate into one or more cell types. Lower animals, such as amphibians, have a much greater capacity than humans to regenerate body parts. For example, axolotls can regenerate an entire limb if one limb is injured. This is because they retain undifferentiated stem cells in their limbs which can be reactivated in the event of injury. Interestingly the adult human brain contains a small population of stem cells. The aim of this project is to find out more about how these cells remain undifferentiated and what is it about them which allows them to form different cell types. If more is known about these cells maybe in the future it will be possible to stimulate them to repair damaged parts of the nervous system. It may also be possible to treat people suffering from diseases like Alzheimer's disease, Parkinson's disease or spinal injuries.Read moreRead less
The Role Of The Mammalian Grainyhead-like Gene Family In Neural Tube Closure
Funder
National Health and Medical Research Council
Funding Amount
$569,541.00
Summary
Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Anencephaly is not compatible with life and affected babies die at birth. In contrast children with spina bifida survive, but suffer from limb paralysis, bowel and bladder dysfunction, learning diff ....Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Anencephaly is not compatible with life and affected babies die at birth. In contrast children with spina bifida survive, but suffer from limb paralysis, bowel and bladder dysfunction, learning difficulties and psycho-social disturbances. Our laboratories have identified a family of genes essential for the colsure of the neural tube in mammals. The aim of this proposal is to understand the mechanisms of action with a view to developing new therapeutics that mey be used preventatively in these conditions. We also hope that these studies may facilitate the development of a genetic test to screen couples at risk.Read moreRead less
We have identified a novel gene, Inpp5e, that when mutated causes a disease similar to Joubert syndrome and MORMS disease which leads to abnormal movements, developmental delays, mental retardation, abnormal breathing and eye movement. We have identified a candidate gene for these diseases and have shown that deletion of this gene in mice results in similar pathology. We aim to determine the mechanism by which Inpp5e regulates human development and disease.