The Molecular Mechanism Of Sphingosine Kinase Activation
Funder
National Health and Medical Research Council
Funding Amount
$442,500.00
Summary
Many cell processes like growth, death and differentiation are controlled by hormones and other molecules that interact with receptors on the outside of the cell. When this type of molecule binds to a receptor, it often triggers the production of signaling molecules inside the cell that initiate a change in the cells behaviour. The lipid molecule, sphingosine phosphate has been identified as such a signaling molecule that appears to be involved in the regulation of a diverse array of important m ....Many cell processes like growth, death and differentiation are controlled by hormones and other molecules that interact with receptors on the outside of the cell. When this type of molecule binds to a receptor, it often triggers the production of signaling molecules inside the cell that initiate a change in the cells behaviour. The lipid molecule, sphingosine phosphate has been identified as such a signaling molecule that appears to be involved in the regulation of a diverse array of important mammalian cellular processes. Recent studies have found that sphingosine phosphate is involved in the inflammation of cells, and if its production can be blocked, inflammation is not seen. Therefore, this provides a potential target for therapeutic intervention in the inflammation process. However, the manner by which cells regulate sphingosine phosphate levels is not well known. It is known that sphingosine phosphate is produced by the enzyme sphingosine kinase, and strong evidence suggests that changes in this enzyme's activity in the cell regulate sphingosine phosphate levels. However, how the cell changes the levels of sphingosine kinase activity is completely unknown. This study will investigate this problem with the view that understanding this process will allow the development of new drugs to block increases in sphingosine kinase activity, preventing increases in sphingosine phosphate levels, and it turn, preventing cellular inflammation.Read moreRead less
Investigating The Pathogenic Mechanisms Of Mutations In The ARX Homeobox Transcription Factor
Funder
National Health and Medical Research Council
Funding Amount
$596,222.00
Summary
Intellectual disability is frequent in the population with as many as 1 in every 50 people in the world directly affected. The cost to Australia of intellectual disability is estimated at $14 billion annually. ARX is one of the most frequent genes mutated in X chromosome linked intellectual disability. Our study will specifically address the functional impact of these mutations using cell models relevant to the brain to better understand the pathways and networks required for normal cognition.
Regulation Of Nuclear Import Of Viral Oncoproteins And Transcription Factors By Protein-protein Interactions
Funder
National Health and Medical Research Council
Funding Amount
$650,383.00
Summary
The present application examines the controls that exerted over proteins that localize in the nucleus of eukaryotic cells. This relates relates integrally to cellular processes such as growth, development and oncogenesis. This research area is not represented elsewhere in Australia, and the particular experimental strategies to approach the problem, revolving around the use of special quantitative microscopic techniques are novel internationally. One part of the application seeks to examine tran ....The present application examines the controls that exerted over proteins that localize in the nucleus of eukaryotic cells. This relates relates integrally to cellular processes such as growth, development and oncogenesis. This research area is not represented elsewhere in Australia, and the particular experimental strategies to approach the problem, revolving around the use of special quantitative microscopic techniques are novel internationally. One part of the application seeks to examine transport within the cell of complexes of interacting proteins, rather than single proteins, under as close as possible to physiologically relevant conditions. This will be truly unique, and of great importance to our comprehension of eukaryotic cell function. This application examines particular types of negative control over protein nuclear localization. Since many proteins show such regulation, and in particular important proteins controlling cell growth and division, the results are fundamentally important to our understanding of how cells function in general. Further, this understanding may be applied in disease situations, such as viral-mediated oncogenesis. In the work we propose to do, viral proteins with functions relating to cancer will be examined in detail, as well as a cellular protein which is recognised by them - the tumor suppressor Rb. We intend to examine several viral oncoproteins which target Rb; one is a protein (E7) from the Human Papilloma Virus which has been frequently associated with cervical carcinomas and other cancers. Accordingly, the results may have direct application to viral-induced cancer, and our work may lead to understanding of the regulation of protein transport to the nucleus. This may thus afford a new approach at the pharmacological level to combat transformation.Read moreRead less
Lipid Metabolism In The Aromatase Knock-out Mouse (ArKO)
Funder
National Health and Medical Research Council
Funding Amount
$408,055.00
Summary
Studies of humans with natural mutations in aromatase, the enzyme responsible for oestrogen biosynthesis, have revealed a number of unexpected roles for oestrogens in both males and females. These discoveries even challenge the definitions of oestrogens and androgens as we now know them. We have created a mouse model of oestrogen insufficiency by targetted disruption of the aromatase gene. These mice display a number of age dependent phenotypes including both male and female infertility, undermi ....Studies of humans with natural mutations in aromatase, the enzyme responsible for oestrogen biosynthesis, have revealed a number of unexpected roles for oestrogens in both males and females. These discoveries even challenge the definitions of oestrogens and androgens as we now know them. We have created a mouse model of oestrogen insufficiency by targetted disruption of the aromatase gene. These mice display a number of age dependent phenotypes including both male and female infertility, undermineralisation of the bones, intra-abdominal obesity, hypercholesterolaemia and insulin resistance. We are addressing the mechanisms of all of those phenotypes but in the present application we focus on the abnormalities in lipid metabolism. Thus we will seek to understand the increase in adiposity by examining the role of oestrogen in lipid synthesis, oxidation and breakdown in adipose tissue from intra-abdominal sites. We will also examine the role that oestrogen plays in cholesterol uptake, synthesis and catabolism by the liver as well as fatty acid synthesis and oxidation by the liver. These studies will be correlated with whole body parameters such as feeding behaviour, physical activity, energy expenditure, glucose and fat oxidation rates. We will also examine the effect of feeding a high cholesterol or a high fat diet on lipid metabolism in the oestrogen deficient animals, and we will determine the effect of oestradiol and isoflavone replacement on the phenotype. In this way we aim to reach a better understanding of the multiplicity of roles that oestrogens play in the regulation of lipid and cholesterol metabolism in both males and females. The results of such studies will be the development of better strategies to deal with pathologies resulting from disturbances in cholesterol and lipid metabolism.Read moreRead less
Mechanisms Of Gender Differences In Genetic Aortopathy
Funder
National Health and Medical Research Council
Funding Amount
$122,686.00
Summary
This project will investigate the molecular mechanisms that underly the gender differences in phenotypic expression in young adults with genetic aortopathy.
Centrosome Overduplication Contributes To Tumorigenesis
Funder
National Health and Medical Research Council
Funding Amount
$495,010.00
Summary
Cancer can be simplistically thought of as a disease of cell growth and division. In order to improve current treatment regimes and identify new ones, the underlying mechanisms controlling cell proliferation need to be fully understood. By defining these regulatory mechanisms, targets for current chemotherapeutic agents can be further characterised and new ones identified. This will lead to the targeted developments of new classes of drugs which can be used in the fight against cancer.
Regulation And Function Of The Protein Tyrosine Phosphatase TCPTP In Mitosis
Funder
National Health and Medical Research Council
Funding Amount
$455,250.00
Summary
The cell cycle is a universal process by which cells reproduce and it underlies the growth and development of all living organisms. The most important events of the cell cycle concern the replication of chromosomal DNA during S phase and the separation of replicated DNA into progeny cells at mitosis. Mitosis is morphologically the most dynamic phase of the cell cycle and involves the precise coordination of many processes that are governed by reversible protein phosphorylation. Protein phosphata ....The cell cycle is a universal process by which cells reproduce and it underlies the growth and development of all living organisms. The most important events of the cell cycle concern the replication of chromosomal DNA during S phase and the separation of replicated DNA into progeny cells at mitosis. Mitosis is morphologically the most dynamic phase of the cell cycle and involves the precise coordination of many processes that are governed by reversible protein phosphorylation. Protein phosphatases play an important role in reversible protein phosphorylation and they are essential for mitosis. This grant proposal is focused on understanding the regulation and function of protein phosphatases in mitosis. Our studies will provide novel insight into processes mediating mitosis and may lead to the development of alternative strategies for treating cancer.Read moreRead less
Nuclear Functions Of Dengue NS5 Protein: Role In Disease
Funder
National Health and Medical Research Council
Funding Amount
$736,953.00
Summary
Our work indicates that the NS5 protein from Dengue virus (DV) has distinct sequences that enable it to traffic into and out of the host cell nucleus to exert pathogenic effects on transcription and thereby impair the host cell anti-viral and immune responses. We aim to characterise these properties in detail, and demonstrate their importance to DV pathogenicity using a novel animal model of the disease.