A Novel Patch-fluorimetry Technique For Investigating Structural Changes During Gating Of Mechanosensitive Ion Channnels
Funder
National Health and Medical Research Council
Funding Amount
$387,018.00
Summary
Membrane proteins, especially membrane channels play an important role in regulating the flow of substances across the cell. Dysfunction in these channels can lead to a variety of diseases. Thus approximately 60% of drug development is targeted against such proteins. In our research, we are looking at membrane channels found in bacteria. Understanding the function of these channels will help us develop novel anti-bacterial agents. It will also aid to understand a role of ion channels in disease.
Trafficking Of The Major Virulence Protein To The Host Cell Surface In Malaria Parasite-infected Erythrocytes
Funder
National Health and Medical Research Council
Funding Amount
$658,164.00
Summary
The malaria parasite infects human red blood cells and causes them to stick to blood vessels in the brain, inducing coma. This causes the deaths of ~2 million children each year. We will use cell biology techniques to manipulate malaria parasites to unravel the details of the molecular ticketing system that the parasite uses to get its adhesive proteins onto the red blood cell surface. The ability to interfere with this process would greatly decrease the impact of this major human pathogen.
Trafficking Of The Cytoadherence-mediating Protein To The Host Cell Surface In Malaria Parasite-infected Erythrocytes
Funder
National Health and Medical Research Council
Funding Amount
$547,315.00
Summary
Malaria kills between 1 and 3 million children each year. In addition, the disease debilitates the adult population in malaria-endemic areas, thereby contributing to the cycle of poverty in many third world countries. As resistance to existing antimalarial drugs increases, there is an urgent need to understand the workings of the parasite at a molecular level to enable the development of alternative antimalarial strategies. During part of its life cycle, the malaria parasite infects the red bloo ....Malaria kills between 1 and 3 million children each year. In addition, the disease debilitates the adult population in malaria-endemic areas, thereby contributing to the cycle of poverty in many third world countries. As resistance to existing antimalarial drugs increases, there is an urgent need to understand the workings of the parasite at a molecular level to enable the development of alternative antimalarial strategies. During part of its life cycle, the malaria parasite infects the red blood cells of its human host. The parasite transports proteins to the red blood cell membrane so as to modify the properties of its adopted cellular residence. The parasite proteins that are deposited at or in the red blood cell membrane increase the leakiness and the stickiness of the parasitised red blood cells. This allows more efficient uptake of nutrients and allows the parasitised red blood cells to adhere to blood vessel walls, thereby avoiding passage through the spleen. Adherence of parasitised red blood cells to capillaries in the brain and the placenta is thought to lead to the development of the complications known as 'cerebral' and 'placental' malaria. These complications are responsible for the deaths of many children and pregnant women. We propose to use cell biology techniques to introduce foreign genes into malaria parasite-infected red blood cells to unravel the details of the molecular machinery and the ticketing system that the parasite uses to traffic its virulence proteins to their correct destinations. These studies could potentially lead to the development of novel intervention strategies. For example, if it were possible to decrease the levels of surface expression of a protein known as PfEMP1, adhesion of infected red blood cells would be inhibited. This would greatly decrease the impact of this important human pathogen.Read moreRead less
Dissecting The Molecular Basis Of The Malaria Parasite-Erythrocyte Tight Junction Complex
Funder
National Health and Medical Research Council
Funding Amount
$547,356.00
Summary
The parasites that cause malaria disease must invade the human red blood cell to complete their lifecycle. Invasion requires the formation of a complex interface between parasite and red cell called the Tight Junction. However, this structure's molecular makeup is entirely unknown. Our research will use a combination of state-of-the-art microscopy and genetics to define, for the first time, the junction's organization, providing a critical platform for the development of a malaria vaccine.
The glomerulus is the filtering component of the kidney. In many diseases, it can be the target of an inappropriate inflammatory response. As part of this response, white blood cells accumulate in the glomerulus where they cause damage. The aim of the project is to determine how these white blood cells accumulate in the glomerulus, specifically asking the question, what molecules present on the white blood cells and the glomerular blood vessels are required for this accumulation?
Nuclear Import Of The HIV-1 Pre-integration Complex: Mechanism And Therapeutic Implications
Funder
National Health and Medical Research Council
Funding Amount
$425,250.00
Summary
The human immunodeficiency virus (HIV) has a unique feature distinguishing it from other retroviruses the ability to replicate in non-dividing cells such as in macrophage-microglia cells which are among the prime target cells for virus infection. The viral genome needs to be integrated into the host cell chromosome in order to infect cells productively. The host cell s genome is not normally accessible because it is located inside the nucleus, separated from the rest of the cell by the barrier o ....The human immunodeficiency virus (HIV) has a unique feature distinguishing it from other retroviruses the ability to replicate in non-dividing cells such as in macrophage-microglia cells which are among the prime target cells for virus infection. The viral genome needs to be integrated into the host cell chromosome in order to infect cells productively. The host cell s genome is not normally accessible because it is located inside the nucleus, separated from the rest of the cell by the barrier of the nuclear envelope (NE). However, HIV has found a way to transport its genome to the nucleus in a complex together with other viral-cellular proteins, the pre-integration complex (PIC), through the intact NE of non-dividing cells. This is a crucial step of viral infection and if blocked could prevent the establishment and spread of HIV infection. Thus far it is unclear how the large HIV PIC accesses the nucleus and which viral and cellular proteins are essential for the navigation of the PIC through the NE and into the nucleus. Using fluorescent labels on the key components of the HIV PIC including the DNA in combination with confocal laser scanning microscopy and a novel optical single-transporter recording technique, we will be able to visualize the PIC on its way through the NE for the first time. Mutational analyses will further identify the key residues of viral proteins and the cellular nuclear transport machinery utilized during the transport. The results of this study will literally provide a clear picture of nuclear import of the HIV PIC. The future aim of elucidating this essential step in HIV replication is to identify new targets for anti-retroviral drug interventions that may be less prone to side effects and development of resistance than the currently available drug regimens.Read moreRead less
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