Active Transport Of Calcium Across Dental Enamel Cells - Testing A New Paradigm
Funder
National Health and Medical Research Council
Funding Amount
$258,000.00
Summary
Dental enamel defects and tooth loss affect over half our population, resulting in substantial suffering and economic costs. It is likely that many enamel defects could be prevented, and replacement teeth made more lifelike, if more was known about the cells responsible for producing enamel. A particular problem is our lack of understanding about how enamel-forming cells avoid overdosing on calcium, which can lead to cellular toxicity. The overall aim of this research is to use the latest cell b ....Dental enamel defects and tooth loss affect over half our population, resulting in substantial suffering and economic costs. It is likely that many enamel defects could be prevented, and replacement teeth made more lifelike, if more was known about the cells responsible for producing enamel. A particular problem is our lack of understanding about how enamel-forming cells avoid overdosing on calcium, which can lead to cellular toxicity. The overall aim of this research is to use the latest cell biology and biochemical techniques to elucidate the mechanisms of calcium handling in enamel cells, with developing teeth from rat as the experimental model. Our focus is on calcium transport mechanisms, a field where past theories were overturned by our recent findings with gene-knockout animals. We will test a new theory that has arisen from our investigations, using drugs and gene-silencing techniques to interfere with the cellular machinery now thought to be crucial for transporting calcium. By providing strong physiological evidence for this new mechanism, our expected results will define specific proteins that might be targeted by drugs and nutrition, and provide important information about how dietary fluoride and caffeine affect enamel quality. These findings would change thinking about how enamel defects can be prevented and provide a solid foundation to the exciting new field of dental bioengineering, whose goal is to coax stem cells to make natural replacement teeth.Read moreRead less
Regulation Of Pre-mRNA And MRNA Processing By The Neuron-specific Hu RNA-binding Proteins
Funder
National Health and Medical Research Council
Funding Amount
$477,750.00
Summary
The precise control of protein expression is absolutely critical in biology, and the key decisions about which genes are turned on or off at any one moment control the proper growth and maturation of an organism during development, and are responsible for the organism's homeostasis and proper response to environmental changes as an adult. Many gene expression programs are highly complex and controlled by regulating the activation of individual genes as they are copied from DNA to RNA. However, t ....The precise control of protein expression is absolutely critical in biology, and the key decisions about which genes are turned on or off at any one moment control the proper growth and maturation of an organism during development, and are responsible for the organism's homeostasis and proper response to environmental changes as an adult. Many gene expression programs are highly complex and controlled by regulating the activation of individual genes as they are copied from DNA to RNA. However, this activation is just the start of the process to produce an active protein. In higher organisms, these RNA copies almost always contain interruptions called introns, which must be excised from the RNA. Also, protein factors bound to specific RNAs can dictate whether the RNA is used to make protein or not, and these factors can also affect the localisation of the RNA to a specific sub-cellular destination, giving rise to highly localised protein expression. Evidence suggests that neurons are a cell type that rely heavily on mechanisms of RNA regulation. During development neurons become highly polarised, acquiring an axon which can elongate and find distant synaptic targets. While much is known about how axon growth cones respond to various guidance cues, the mechanisms by which the axon is able to translate this guidance cue information into structural changes which allow the growth cone to expand or collapse is largely unexplored. Recent evidence suggests that accurate growth cone guidance is absolutely dependent upon local protein synthesis. The functional corollary of this finding is that axon guidance requires RNA localisation and control of protein synthesis of RNAs in the growth cone. This phenomenon of spatial gene regulation within an individual cell is a central research interest for understanding how the brain functions.Read moreRead less
MRNA Surveillance In Human Disease: Molecular Determinants Of Nonsense-mediated MRNA Decay
Funder
National Health and Medical Research Council
Funding Amount
$474,517.00
Summary
Inherited diseases are a common cause of human disability, illness and suffering. It has been estimated that 5-10% of the population will be affected by disorders with a genetic component. Thus studies on mechanisms of inherited diseases, especially those relating to genetic mechanisms with relevance across a wide range of individual disorders and gene mutations, are of great significance in diagnosis, molecular pathology and the eventual development of therapeutics. While there are many types o ....Inherited diseases are a common cause of human disability, illness and suffering. It has been estimated that 5-10% of the population will be affected by disorders with a genetic component. Thus studies on mechanisms of inherited diseases, especially those relating to genetic mechanisms with relevance across a wide range of individual disorders and gene mutations, are of great significance in diagnosis, molecular pathology and the eventual development of therapeutics. While there are many types of mutations, one relatively common type is called a premature termination mutation. Premature termination mutations introduce an inappropriate genetic signal that tells the cells to stop the formation of proteins before they are complete. This would result in the production of a protein that is shorter than normal, and these short proteins could be quite abnormal and drastically affect the normal function of cells. To overcome this, cells have developed elegant strategies that involve the deployment of quality control, or surveillance, mechanisms to remove the mutant gene product before it can be converted into an abnormal protein. This process is called nonsense mediated decay. Nonsense mediated decay is a complex process and some of the key components have been identified by studies on a small number of genes. However, our studies have identified several previously unknown aspects of the process that suggest that the currently held view of how nonsense mediated decay works is only the beginning of the story and further important complexity exists. The proposed research will explore the basic mechanisms of the surveillance process and determine the signals that initiate nonsense mediated decay. Since premature termination mutations cause one-third of all inherited genetic disorders, our studies will provide new insights into the surveillance mechanisms and will have wide applicability to our understanding of the basis of inherited disease.Read moreRead less