Our bodies generate a hormone called angiotensin II in response to a decrease in blood pressure (or salt in our bloodstream). This hormone increases blood pressure by causing blood vessels to constrict, by making us thirsty, and by inducing salt and fluid retention via an effect on the kidneys. In some cardiovascular diseases, the generation of angiotensin II or our sensitivity to this hormone is elevated. It is therefore crucial that we understand how angiotensin II works and how its actions in ....Our bodies generate a hormone called angiotensin II in response to a decrease in blood pressure (or salt in our bloodstream). This hormone increases blood pressure by causing blood vessels to constrict, by making us thirsty, and by inducing salt and fluid retention via an effect on the kidneys. In some cardiovascular diseases, the generation of angiotensin II or our sensitivity to this hormone is elevated. It is therefore crucial that we understand how angiotensin II works and how its actions in the body are mediated. For angiotensin II to act it must first bind to a receptor. Receptors are proteins and behave like locks that are opened by the hormone keys. Thus, cellular receptors for angiotensin II are engaged and activated by increases in angiotensin II in our blood. These receptors then produce signals which initiate a response (e.g. constriction of a blood vessel). Subsequently, the receptors are switched-off to prevent over-stimulation. The experiments proposed in this application continue our investigations into how angiotensin II receptors are regulated or switched-on and -off. A major way for receptors to be turned off is for them to be ear-marked by a modification known as phosphorylation. These modified receptors are then bound by proteins termed arrestins, which as indicated by their name play a role in preventing further receptor signalling. These arrestins also help remove activated receptors from the cell surface to the inside of the cell. How arrestins interact with receptors and regulate their function is poorly understood. This application proposes experiments to investigate the molecular mechanisms of arrestin action as it relates to the angiotensin II receptor. Results from these studies will further our understanding of angiotensin II receptors and their role in cardiovascular control.Read moreRead less
The hormone angiotensin II affect our heart and blood vessels by switching-on receptors that are then switched-off to prevent over-stimulation. This application continues our investigations into how angiotensin II receptors are switched-on and -off. We apply new technologies to identify and study receptor modulating proteins and the pairing receptors into dimers. Results will further our understanding of angiotensin receptors and cardiovascular control.
Molecular Regulation Of The Type 1 Angiotensin Receptor
Funder
National Health and Medical Research Council
Funding Amount
$695,440.00
Summary
Angiotensin II is a hormone made in our bodies in response to a decrease in blood pressure (or salt in our bloodstream). It causes our blood vessels to constrict, makes us thirsty, and induces salt and fluid retention via an effect on the kidneys, thereby increasing blood pressure. In some cardiovascular diseases, the generation of angiotensin II or our sensitivity to this hormone is elevated. It is therefore crucial that we understand how angiotensin II works and how its actions in the body are ....Angiotensin II is a hormone made in our bodies in response to a decrease in blood pressure (or salt in our bloodstream). It causes our blood vessels to constrict, makes us thirsty, and induces salt and fluid retention via an effect on the kidneys, thereby increasing blood pressure. In some cardiovascular diseases, the generation of angiotensin II or our sensitivity to this hormone is elevated. It is therefore crucial that we understand how angiotensin II works and how its actions in the body are mediated. For angiotensin II to act it must first bind to a receptor. Receptors are proteins and behave like locks that are opened by the hormone keys. Thus, cellular receptors for angiotensin II are engaged and activated by increases in angiotensin II in our blood. These receptors then produce signals which initiate a response (e.g. constriction of a blood vessel). Subsequently, the receptors are switched-off to prevent over-stimulation. The experiments proposed in this application continue our investigations into how angiotensin II receptors are switched-on and -off. A major way for receptors to be turned on is for them to interact with other cellular proteins, although we know only some of these interactions for the angiotensin receptor. Receptors are turned off by being ear-marked by a modification known as phosphorylation; these modified receptors are then bound by proteins termed arrestins, which as indicated by their name, play a role in preventing further receptor signalling. These arrestins also help to remove activated receptors from the cell surface to the inside of the cell. This application proposes new technologies to investigate the spectrum of proteins recruited to the angiotensin receptor and the role of arrestins in switching receptors on and off. Results from these studies will further our understanding of angiotensin II receptors and their role in cardiovascular control.Read moreRead less
Characterisation Of Anti-HBs Responses In Patients Undergoing Functional Hepatitis B Cure: Implication For Future Therapies
Funder
National Health and Medical Research Council
Funding Amount
$723,649.00
Summary
The hepatitis B virus causes liver cirrhosis and liver cancer. There is no cure for hepatitis B. However, a small number of patients can naturally rid themselves of the virus. We have identified 14 of these individuals and discovered that they have a unique immune response that is responsible for these “natural” cures. We plan to characterise this immune response and turn it into a therapeutic vaccine which can be used to cure patients who are still chronically infected.
A New Insight Into Hepatitis B Infection:the HBV Fusion Peptide
Funder
National Health and Medical Research Council
Funding Amount
$288,210.00
Summary
Three hundred and fifty million people worldwide and 250,000 in Australia are chronically infected with hepatitis B virus (HBV). Without intervention, one third will die as a direct result of this infection through cirrhosis, liver failure and liver cancer, but current therapies are inadequate. New antiviral treatments requiring the identification of new antiviral targets are needed to combat the disease but a major obstacle to the study of HBV is the lack of a cell culture system. As a result n ....Three hundred and fifty million people worldwide and 250,000 in Australia are chronically infected with hepatitis B virus (HBV). Without intervention, one third will die as a direct result of this infection through cirrhosis, liver failure and liver cancer, but current therapies are inadequate. New antiviral treatments requiring the identification of new antiviral targets are needed to combat the disease but a major obstacle to the study of HBV is the lack of a cell culture system. As a result nothing is known about how HBV enter and fuses with the host liver cell but we have made significant progress with the identification of the entry and fusion events of the related duck hepatitis B virus, using the duck infection model. This knowledge is now ready for application to the medically important HBV by use of primary human liver cells and the techniques developed in the duck hepatitis B virus model.Read moreRead less
Towards A Functional Cure For HBV: Exploiting Lessons From HBV-HIV Co-infection
Funder
National Health and Medical Research Council
Funding Amount
$913,551.00
Summary
Hepatitis B virus (HBV) infection can be treated, but therapy is usually lifelong and has side effects, so a cure for HBV is very important. We work closely with colleagues in Asia where both HBV and HIV are common so this provides a unique opportunity to study HBV. We will investigate how an effective immune response against the 2 main HBV proteins is developed. If we can understand how the immune response works against HBV, this could be used to develop new therapies to develop a cure for HBV