The Role Of Netrin-DCC In The Development Of The Corpus Callosum
Funder
National Health and Medical Research Council
Funding Amount
$512,065.00
Summary
During embryonic development neurons send out axons that connect to other target neurons within the brain. The proper connectivity of these axons is vital to brain function. The largest axon tract in the brain is called the corpus callosum and connects neurons in the left and right cerebral hemispheres. When the corpus callosum does not form, significant cognitive, motor and sensory deficits occur in patients. This condition, known as agenesis of the corpus callosum (ACC), is associated with ove ....During embryonic development neurons send out axons that connect to other target neurons within the brain. The proper connectivity of these axons is vital to brain function. The largest axon tract in the brain is called the corpus callosum and connects neurons in the left and right cerebral hemispheres. When the corpus callosum does not form, significant cognitive, motor and sensory deficits occur in patients. This condition, known as agenesis of the corpus callosum (ACC), is associated with over 50 different human congenital syndromes. Thus understanding how the genes and molecules involved in the formation of the corpus callosum function in normal development can provide the basis for our understanding of what goes wrong in ACC. In this proposal we will investigate the role of the axon guidance molecule Netrin1, and its receptor DCC, in development of the corpus callosum in both a mouse model and in humans with malformations of the corpus callosum. Although Netrin1-DCC signalling has traditionally been associated with mechanisms of axon guidance, we hypothesize that these molecules may play a different role, specifically in cellular adhesion and ultimately in the fusion of the two cerebral hemispheres, in a manner that allows the corpus callosum to form. A second role for Netrin1-DCC signalling may be in the guidance of these axons once the midline has fused correctly and we investigate this in Aim 2 of the proposal. Finally, we are collaborating with a paediatric neurologist at UCSF, who has identified several mutations in the DCC gene in patients with ACC. In Aim 3 we test whether these mutations disrupt the function of DCC in callosal axon pathfinding. Understanding how these genes function during development of the brain and how their function may be altered in ACC is crucial to providing a proper diagnosis and prognosis for these patients. Ultimately, understanding more about how these genes function could also lead to prevention of these disorders.Read moreRead less
Tuberous Sclerosis And Epilepsy: Using Resected Tissue To Understand Pathogenesis And Inform Management
Funder
National Health and Medical Research Council
Funding Amount
$339,261.00
Summary
Epilepsy is the commonest neurological disorder in childhood and seizures cannot be fully controlled by medications in 30%, often leading to developmental consequences. A major cause of drug-resistant epilepsy is a malformation of the brain’s surface. Surgery is sometimes used to remove these lesions to treat the epilepsy. We will study this tissue to understand its architecture, genetic basis and how it causes seizures. Our results will guide treatment including the best surgical approach.
Selective Isolation And In Vivo Properties Of Dopamine Neurons Generated From Embryonic Stem Cells.
Funder
National Health and Medical Research Council
Funding Amount
$505,389.00
Summary
This research aims to develop a procedure that allows for the safe and effective use of stem cells as a therapy for Parkinson’s disease. It is based on the concept that new dopamine neurons, generated from stem cells, can be implanted into the brain of the patients in order to replace those lost to the disease, thereby improving motor function.
Blood-brain Barrier And White Matter Damage In The Immature Rat Brain Following Systemic Inflammation
Funder
National Health and Medical Research Council
Funding Amount
$353,173.00
Summary
Clinical obstetric and paediatric studies have identified an association between intrauterine infection occurring around two thirds of the way through pregnancy, premature birth and a specific form of damage to the brain of the newborn. This damage mainly affects white matter tracts. These tracts are aggregations of nerve fibres that make the connections between different parts of the brain and may result in cerebral palsy or other neurological disorders. The association between maternal infecti ....Clinical obstetric and paediatric studies have identified an association between intrauterine infection occurring around two thirds of the way through pregnancy, premature birth and a specific form of damage to the brain of the newborn. This damage mainly affects white matter tracts. These tracts are aggregations of nerve fibres that make the connections between different parts of the brain and may result in cerebral palsy or other neurological disorders. The association between maternal infection and brain damage, one form of which is cerebral palsy, is well established from clinical epidemiological studies, but the biological mechanism of this link is unknown. The CIs' group has recently shown that the condition can be reproduced in neonatal rats at a stage of brain development in the rat that is equivalent to the critical time in human brain development when infection may be associated with brain damage. The CIs' group has shown that an induced inflammatory state similar to a bacterial infection, results in damage to blood vessels in the white matter and is associated with changes in white matter, as occurs in affected babies. The purpose of this study is to understand the nature of the damage to white matter blood vessels and the mechanisms by which materials in blood, which in the normal brain do not pass from the blood to the brain across the blood-brain barrier, are able to do so via the inflammation damaged blood vessels. The study also aims to show whether it is components of the blood entering the brain via the damaged blood vessels that are responsible for the damage to white matter in the immature brain. The outcome should lead to development of ways to improve clinical care of women who acquire infections during pregnancy.Read moreRead less
What shapes our brain? This project aims to improve our fundamental understanding of the biological mechanisms that drive folding of the cerebral cortex, which occurs during development of the brain. Cortical folding is unique to humans and higher mammals, and is thought to underpin the emergence of intelligence and contribute to higher-order brain functions. This project will enhance knowledge of how the cerebral cortex folds and develop novel tools for analysing brain development. The project ....What shapes our brain? This project aims to improve our fundamental understanding of the biological mechanisms that drive folding of the cerebral cortex, which occurs during development of the brain. Cortical folding is unique to humans and higher mammals, and is thought to underpin the emergence of intelligence and contribute to higher-order brain functions. This project will enhance knowledge of how the cerebral cortex folds and develop novel tools for analysing brain development. The project will provide significant benefits including the generation of fundamental knowledge with implications for future understanding of cortical folding abnormalities in babies born preterm, following fetal growth retardation in utero, or when exposed to maternal alcohol. In the longer term, the project will contribute to improvements to human neurodevelopment and brain health.Read moreRead less
Modelling human brain development with stem cells and biomaterials. With limited resources to directly study and advance our understanding of human neural development, this
proposal will establish models of 4 key stages. Employing innovative, interdisciplinary approaches, biomaterials will be fabricated to provide structural and chemical support for human stem cells during: (i) neural induction, (ii) specification into neuronal progenitor subpopulations, (iii) neuronal maturation and integration ....Modelling human brain development with stem cells and biomaterials. With limited resources to directly study and advance our understanding of human neural development, this
proposal will establish models of 4 key stages. Employing innovative, interdisciplinary approaches, biomaterials will be fabricated to provide structural and chemical support for human stem cells during: (i) neural induction, (ii) specification into neuronal progenitor subpopulations, (iii) neuronal maturation and integration into complex neural networks as well as, (iv) the organisation of neurons into larger 3-dimensional brain structures, namely folding of the human cortex. Further, biomaterials developed here have commercialisation potential, targeted at standardizing the culturing of human stem cells to defined neural populations.
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Subcellular recruitment of a RhoA ubiquitination complex by Rnd proteins. This study addresses a novel molecular mechanism through which members of the Rnd family of GTP-binding proteins regulate the morphology and migration of immature nerve cells of the developing nervous system. This study has broad implications for the understanding of cell migration during embryo development, as well as in health and disease.
Enhancing neurogenesis in the adult primate brain. New neurons are robustly generated in the subependymal zone (SEZ) during human development. Thus, the SEZ may represent an endogenous modifiable source of neurons to enhance plasticity and therapeutic potential in the brain. However, despite our preliminary data, SEZ neurogenesis beyond the first months of life is controversial. This project aims to understand changes in the capacity for human SEZ proliferation from birth through to ageing and w ....Enhancing neurogenesis in the adult primate brain. New neurons are robustly generated in the subependymal zone (SEZ) during human development. Thus, the SEZ may represent an endogenous modifiable source of neurons to enhance plasticity and therapeutic potential in the brain. However, despite our preliminary data, SEZ neurogenesis beyond the first months of life is controversial. This project aims to understand changes in the capacity for human SEZ proliferation from birth through to ageing and whether neurogenesis may be induced by inflammation in the adult. Using transcriptomics we will also determine how the neurogenic environment changes with age/inflammation. This project is an important step in proving that the brain's potential to generate new neurons extends beyond infancy.Read moreRead less
Targeting Central Inflammation To Combat Obesity And Obesity-related Cognitive Dysfunction
Funder
National Health and Medical Research Council
Funding Amount
$470,144.00
Summary
The current obesity epidemic means many of us will suffer from overweight or obesity for at least some of our lives. My findings show obesity can cause inflammation throughout the brain including in regions related to learning and memory. Here I hypothesize that obesity induces long-term changes in the brain’s immune cells, that this can explain why we see susceptibility to cognitive decline in obese individuals, and that we can reverse these negative effects by targeting these immune cells.