The Molecular Basis For Target Selection In The Central Nervous System By Sensory Axons
Funder
National Health and Medical Research Council
Funding Amount
$251,325.00
Summary
The normal function of the brain depends upon the specific connections that nerve cells make with each other. These connections are set up in the developing embryo when nerve cells send out long processes - axons - which grow towards their synaptic targets. How axons select their correct targets from amongst the millions of alternatives in the developing brain is unknown. A better understanding of this problem will help us develop therapies to assist regenerating axons re-establish correct conne ....The normal function of the brain depends upon the specific connections that nerve cells make with each other. These connections are set up in the developing embryo when nerve cells send out long processes - axons - which grow towards their synaptic targets. How axons select their correct targets from amongst the millions of alternatives in the developing brain is unknown. A better understanding of this problem will help us develop therapies to assist regenerating axons re-establish correct connections following injury to the brain or spinal cord. We propose to use a simple model system, the embryo of the fruitfly Drosophila, to find molecules that are involved in this process of neuron target recognition - ' axon targeting' molecules - and to study how they work. Drosophila can be genetically manipulated in ways not possible in higher animals. Furthermore the simplicity of its nervous system means that we can determine the connections of individual nerve cells with a high degree of precision. In the first part of our project, we will examine Drosophila embryos that carry mutations in genes suspected to code for targeting molecules. We will stain individual sensory nerve cells in these embryos with dyes to reveal the anatomy of their axons in the brain. If sensory axons terminate abnormally in the brain of a given mutant, the affected gene is likely to code for an axon targeting molecule. In the second part of the study, we will investigate the functions of candidate axon targeting molecules using two approaches. Firstly, we will seek to determine whether the molecule acts in the sensory axons or in their target cells. Secondly, we will use time-lapse microscopy to study how the homing behaviour of the sensory axons is affected in mutant embryos. The results of these studies will lead us closer to an answer to the question: How do axons recognise their specific target cells in the brain?Read moreRead less
The Role Of Cell Adhesion Molecules In Regulation Of Axon Advance
Funder
National Health and Medical Research Council
Funding Amount
$426,006.00
Summary
All cells contain on their surface a class of molecules, cell adhesion molecules, that enable them to adhere to other cells in tissues. Cell adhesion molecules have long been known to be involved in the guidance of axons to their targets during development. However the molecular mechanisms by which these molecules act are largely unknown. We propose to use the powerful genetic tools available in the fruitfly to dissect the mechanisms by which two cell adhesion molecules promote axon growth.
Understanding The Origins Of Neurogenic Hypertension
Funder
National Health and Medical Research Council
Funding Amount
$668,914.00
Summary
Brain cells that control the cardiovascular system are thought to have stopped dividing by adulthood. We recently discovered that this is not the case. Our initial findings suggest that these nascent cells might be important for maintaining normal blood pressure. This work will allow us to elucidate the function of these nascent cells and how they integrate into the circuit that controls the cardiovascular system. Our findings will be fundamental for understanding diseases such as hypertension.
Molecular Targets Of Amino Acid/neurotransmitter Conjugates Of Fatty Acids
Funder
National Health and Medical Research Council
Funding Amount
$846,390.00
Summary
This project investigates endogenous chemicals that affect cells important for detecting and responding to pain. We aim to discover how these compounds affect proteins important for nerve cell function, particularly proteins that have a prominent role in detecting and transmitting painful events. The compounds we examine are not themselves likely to be drugs, but future therapies may involve manipulating the levels of these chemicals in the body, or using drugs that mimic the activity of these c ....This project investigates endogenous chemicals that affect cells important for detecting and responding to pain. We aim to discover how these compounds affect proteins important for nerve cell function, particularly proteins that have a prominent role in detecting and transmitting painful events. The compounds we examine are not themselves likely to be drugs, but future therapies may involve manipulating the levels of these chemicals in the body, or using drugs that mimic the activity of these compounds.Read moreRead less
Centre-surround interactions in ageing human vision. Australia has a rapidly ageing population. This project will study how ageing affects the visual perception of objects presented on non-uniform backgrounds. Our ability to discriminate objects from their backgrounds is key to most natural visual tasks. The visual processes involved are known as centre-surround interactions, and are considered fundamental building blocks to human perception. This project will significantly advance our knowledge ....Centre-surround interactions in ageing human vision. Australia has a rapidly ageing population. This project will study how ageing affects the visual perception of objects presented on non-uniform backgrounds. Our ability to discriminate objects from their backgrounds is key to most natural visual tasks. The visual processes involved are known as centre-surround interactions, and are considered fundamental building blocks to human perception. This project will significantly advance our knowledge of which spatial visual mechanisms are altered due to age, supplying key information for understanding and improving visual environments for the elderly, as well as increasing knowledge of the brain mechanisms susceptible to the ageing process.Read moreRead less
Chromatic Inputs to Cortical Receptive Fields in Primates. The human eye contains three kinds of receptors for daytime vision, named blue, green and red cones for their sensitivity to different regions of the visible spectrum. It is known that blue cones contribute to brain pathways for colour vision, but recent data suggest there is also 'cross-talk' of blue cone signals to pathways for motion and high-acuity vision. This project comprises precise measurement of blue cone signals, and anatomica ....Chromatic Inputs to Cortical Receptive Fields in Primates. The human eye contains three kinds of receptors for daytime vision, named blue, green and red cones for their sensitivity to different regions of the visible spectrum. It is known that blue cones contribute to brain pathways for colour vision, but recent data suggest there is also 'cross-talk' of blue cone signals to pathways for motion and high-acuity vision. This project comprises precise measurement of blue cone signals, and anatomical tracing of blue cone pathways, in a primate model for human vision. The data will improve our basic knowledge of how the brain processes sensory signals.Read moreRead less
The Claustrum Enigma: Unlocking The Role Of The Last Unknown Area Of The Primate Brain
Funder
National Health and Medical Research Council
Funding Amount
$558,364.00
Summary
Despite nearly 200 years of study, the function of the claustrum remains unclear. Interest in this brain structure has recently been revived by findings showing damage to the claustrum in several major diseases, and by the suggestion that the claustrum may have a role in consciousness. Here we propose a series of experiments to test the novel hypothesis that the claustrum is part of the default mode network, a group of brain areas that act together when we aren't thinking about anything in parti ....Despite nearly 200 years of study, the function of the claustrum remains unclear. Interest in this brain structure has recently been revived by findings showing damage to the claustrum in several major diseases, and by the suggestion that the claustrum may have a role in consciousness. Here we propose a series of experiments to test the novel hypothesis that the claustrum is part of the default mode network, a group of brain areas that act together when we aren't thinking about anything in particular, that is- most of the time.Read moreRead less
Neural plasticity in older adult human vision. This project aims to expand our understanding of age related changes in brain function, specifically plasticity. The project will increase knowledge of the role of an inhibitory neurotransmitter GABA in visual plasticity. Expected outcomes include new knowledge regarding the regulation of brain function in adulthood, enabling future research and planning for societal benefit to older Australia.
The brain in real-time: predicting the present, reconstructing the past. This proposal aims to understand how the brain compensates for its own internal delays to function in real-time. Because it takes time for information from the senses to reach the brain, it takes time for us to become aware of an event that occurs in the outside world. This project will use an innovative combination of techniques to study how prediction and reconstruction mechanisms work together in the brain. Expected outc ....The brain in real-time: predicting the present, reconstructing the past. This proposal aims to understand how the brain compensates for its own internal delays to function in real-time. Because it takes time for information from the senses to reach the brain, it takes time for us to become aware of an event that occurs in the outside world. This project will use an innovative combination of techniques to study how prediction and reconstruction mechanisms work together in the brain. Expected outcomes of this project include a fundamental understanding of how we function in the present. This should provide significant benefits, such as an important theoretical advance in our understanding of how conscious awareness is realised in the brain, placing Australia at the cutting edge.Read moreRead less
The brain in real time: a neural model of rhythmic action and perception. This project aims to study a fundamental function of the human brain: its temporal architecture. It will provide an innovative perspective on the neural mechanisms underlying and relating perception, intention, and voluntary action in real time, though a combination of eye-tracking, behaviour, and neural recordings. By providing a common language with which to relate perception, cognition, volition and action, this will ....The brain in real time: a neural model of rhythmic action and perception. This project aims to study a fundamental function of the human brain: its temporal architecture. It will provide an innovative perspective on the neural mechanisms underlying and relating perception, intention, and voluntary action in real time, though a combination of eye-tracking, behaviour, and neural recordings. By providing a common language with which to relate perception, cognition, volition and action, this will provide significant benefits that will transform the way we think about brain function.Read moreRead less