Down syndrome (DS) individuals have 3 copies of chromosome 21. I am proposing to do my PhD to investigate the role of a gene existing on chromosome 21 called Intersectin 1. This gene, when over-expressed might be responsible for manifestation of intellectual impairment in Down syndrome. I will be examining the consequence of altered/over-expression of this gene in receptor trafficking, cell signalling and histology of the brain to identify the differences between affected individuals and the nor ....Down syndrome (DS) individuals have 3 copies of chromosome 21. I am proposing to do my PhD to investigate the role of a gene existing on chromosome 21 called Intersectin 1. This gene, when over-expressed might be responsible for manifestation of intellectual impairment in Down syndrome. I will be examining the consequence of altered/over-expression of this gene in receptor trafficking, cell signalling and histology of the brain to identify the differences between affected individuals and the normal population.Read moreRead less
How The Dosage Of A Down Syndrome Candidate Gene Affects Neural Circuitry And Behaviour
Funder
National Health and Medical Research Council
Funding Amount
$414,961.00
Summary
In Down syndrome, an extra copy of chromosome 21 increases gene expression and leads to brain defects. We hypothesise that one candidate gene, Dscam2, changes its function with increased expression. This causes brain cells that normally stick to each other to repel each other, leading to inappropriate connections in the brain. We will test this model in the fruit fly and demonstrate for the first time a mechanism dependent on gene expression that can lead to brain abnormalities in Down syndrome.
The Role Of Down Syndrome Candidate Region 1 (DSCR1) In Neurotransmitter Release, Vesicle Recycling And Down Syndrome.
Funder
National Health and Medical Research Council
Funding Amount
$352,318.00
Summary
Individuals with Down syndrome (DS) have three copies of human chromosome 21 (HSA21), rather than the normal two. The symptoms observed in DS individuals are therefore due to the overexpression of HSA21 genes. Since all individuals with DS develop symptoms in the brain similar to those see in Alzheimer's disease (AD), there may be a common mechanism that can be traced to the extra gene dosage from HSA21. We are interested in one of these genes, Down syndrome candidate region 1 (Dscr1), which is ....Individuals with Down syndrome (DS) have three copies of human chromosome 21 (HSA21), rather than the normal two. The symptoms observed in DS individuals are therefore due to the overexpression of HSA21 genes. Since all individuals with DS develop symptoms in the brain similar to those see in Alzheimer's disease (AD), there may be a common mechanism that can be traced to the extra gene dosage from HSA21. We are interested in one of these genes, Down syndrome candidate region 1 (Dscr1), which is overexpressed in both DS and AD brains. We hypothesise that Dscr1 has a role in regulating exocytosis, a process in which chemical messengers are released from cells. Exocytosis is highly specialised in the brain where neurotransmitters are released from neuronal synapses in a process known as synaptic transmission. Reduced synaptic transmission is one of the earliest hallmark of DS and AD occurring long before the classical neurological traits of DS and AD such as plaque formation and dementia. We propose that alterations in Dscr1 expression are responsible for the reduced neuronal exocytosis observed in the early stages of DS and AD. We have generated mice in which Dscr1 expression is altered, as occurs in DS and AD brains, and our preliminary studies indicate that exocytosis is reduced in these mice. We now wish to find the intracellular changes responsible for regulating exocytosis when Dscr1 expression is altered. We also aim to compare this to exocytosis in classical DS mouse models which have an extra chromosome 21 and in similar DS mouse models which have normal levels of Dscr1. This project will uncover the currently unknown functions of Dscr1 in exocytosis in an animal model, allow us to gauge whether Dscr1 is solely responsible for altering exocytosis in DS amongst other HSA21 genes, enable us to better understand the mechanisms initiating DS and AD and possibly lead to new targets of early intervention in these diseases.Read moreRead less
Defining Reciprocal Neural Circuits That Regulate Appetite And Memory
Funder
National Health and Medical Research Council
Funding Amount
$341,935.00
Summary
How we remember meals influences how much we eat at later time points. This kind of memory likely comes from both the traditional brain areas associated with memory formation, and from areas associated with regulating appetite. How these two brain regions work together to help animals remember what they ate, where they found it, and whether they liked it is not known. This project investigates how these memories are formed and how they are used by animals to make decisions about future meals.
The brain regulates body temperature by a series of mechanisms, including the control of how much blood flows to the skin to lose or retain heat. The project aims to locate the brain temperature receptors and brain pathways that do this, using an animal model, the rat. At present they are not known.
I am a neuroscientist investigating the functional roles of neurotrophic factors in nervous diseases such as Alzheimer’s disease and spinal cord injury. I am also interested in the mechanisms of how these factors are involved in neural development.
Understanding How The Brain Senses And Encodes Hunger And Satiety
Funder
National Health and Medical Research Council
Funding Amount
$473,477.00
Summary
Obesity is the most important health concern in the world today. Despite all the epidemiology evidence and despite the intervention approaches, obesity and type-2 diabetes continues to rise in Australia and worldwide. Clearly, a greater biological understanding of the mechanisms driving increased calorie intake and decreased calorie expenditure. This fellowship explores the different neural circuits in the brain and how they regulate motivation for food and food consumption
Understanding The Molecular Basis Of Central Nervous System Myelination
Funder
National Health and Medical Research Council
Funding Amount
$408,388.00
Summary
Oligodendrocytes are the cell type in the central nervous system that produce myelin, the insulating layer around nerve cells. Loss of oligodendrocytes and myelin are key features of multiple sclerosis. This project aims to clarify the mechanisms that control the myelination of nerve cells during normal development, allowing the development of strategies to promote myelin repair in human diseases such as Multiple Sclerosis.
Understanding The Contribution Of Iron In Traumatic Brain Injury
Funder
National Health and Medical Research Council
Funding Amount
$601,263.00
Summary
Our group has discovered a novel role of amyloid precursor protein (APP) in cellular iron balance similar to another protein called ceruloplasmin (CP). Both, prevalently found in the brain, convert a damaging iron variety into the safer form. Disruption in either protein leads to cell death. We aim to establish how failure in APP and CP response may be detrimental to traumatic brain injury recovery. Understanding the iron role of APP and CP will lead to therapeutics to counter traumatic injury.
The Role Of Long Noncoding RNAs In Parkinson’s Disease
Funder
National Health and Medical Research Council
Funding Amount
$692,699.00
Summary
Parkinson's disease is a complex neurodegenerative disorder. For 90% of patients there is no known cause and for all patients there is no cure. The development of genome studies and transcriptome sequencing has revealed a class of noncoding RNAs whose regulation or dysregulation may lay at the heart of what goes wrong for PD sufferers. Our laboratory focuses on critical PD genes and their regulation by long noncoding RNAs.