Role Of Conformational Change In Activation Of The Growth Hormone Receptor
Funder
National Health and Medical Research Council
Funding Amount
$242,545.00
Summary
Growth hormone is an important hormone therapeutic for treating dwarfism. Recently, many new therapeutic applications for growth hormone have been discovered, particularly in relation to its role as an anabolic agent. These include post surgery recovery, enhanced bone fracture healing, Crohns disease, dilated cardiomyopathy, infertility and of course, ageing. This project seeks to find out how growth hormone sends its signal into the target cell through its surface receptor. It is believed that ....Growth hormone is an important hormone therapeutic for treating dwarfism. Recently, many new therapeutic applications for growth hormone have been discovered, particularly in relation to its role as an anabolic agent. These include post surgery recovery, enhanced bone fracture healing, Crohns disease, dilated cardiomyopathy, infertility and of course, ageing. This project seeks to find out how growth hormone sends its signal into the target cell through its surface receptor. It is believed that the primary event in signalling is the ability of the hormone to bring two receptors together (receptor dimerization). However, it may be that the receptor already is dimerized, and the role of the hormone is to induce a specific change in shape of the receptor, which transfers the signal of hormone binding into the cell to initiate signalling to the genome. We have good evidence that a specific shape change is required for activation of an important signalling pathway by growth hormone, and the closely structurally related receptor for erythropoietin is already dimerized before hormone binds. We want to find out exactly how the shape change acts, and whether the receptor is predimerized. This information is vital for designing small orally active mimics of growth hormone which could be of great value as an anabolic supplement for the frail elderly.Read moreRead less
Novel G-protein Coupled Receptor Interactions And Complexes With Distinct Function And Pharmacology
Funder
National Health and Medical Research Council
Funding Amount
$246,760.00
Summary
G protein coupled receptors (GPCRs) are the target in the human body for most of today's medicines. Almost all pharmaceutical companies market drugs that are GPCR agonists or antagonists aimed at diverse disease states. Our research is focused on the molecular basis of drug recognition and signalling by GPCRs. We use genetic engineering techniques to create new receptors and mutant receptors in order to identify the functional domains of these signalling molecules. We have recently established a ....G protein coupled receptors (GPCRs) are the target in the human body for most of today's medicines. Almost all pharmaceutical companies market drugs that are GPCR agonists or antagonists aimed at diverse disease states. Our research is focused on the molecular basis of drug recognition and signalling by GPCRs. We use genetic engineering techniques to create new receptors and mutant receptors in order to identify the functional domains of these signalling molecules. We have recently established a novel approach based on proximity-dependent fluorescent technologies to explore receptor interactions and have described the formation of functional G-protein coupled complexes in living cells. This project is to discover new receptor combinations which could potentially affect signalling pathways and redirect cellular responses. Investigation of the mechanisms involved in turning on and off the body s response to stimuli would provide valuable information for drug design and treatment of GPCR-related conditions. We have chosen to use two GPCRs as models for our study of the mechanisms controlling receptor driven cellular responses and the interactions between cellular components-proteins behind this control. Firstly, the gonadotropin releasing hormone receptor (GnRHR), a protein located in the pituitary which is pivotal in the control of reproduction and secondly, the thyrotropin releasing hormone receptor (TRHR), similarly located and involved in modulating thyroid and metabolic function. We will investigate the way these receptors interact with other cellular proteins in order for them to function. Ultimately this will provide a better understanding of how these clinically important proteins function and pave the way for the development of clinical applications that target these receptor systems, resulting in the effective treatment of a wide range of conditions and diseases, including pain, migraine, certain forms of cancer, neurological and reproductive disorders.Read moreRead less
Characterisation Of A New Family Of Proteins Involved In Cell Signalling, RNA Metabolism And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of th ....We have discovered a novel RNA-binding protein (G3BP-2) that is involved in responding to external signals, such as growth factors, at the level of gene expression. Other RNA-binding proteins belonging to the same broad group of proteins are responsible for a host of disease states in mammals including mental retardation, myotonic dystrophy, Huntington?s disease and cancers. Considering the wealth of knowledge accumulated that implicates these proteins to human dysfunction surprisingly few of these RNA-binding proteins have been identified. We have shown that the novel protein discovered in our laboratory is perturbed in cancer and we are interested in characterising its putative role in cancer. The results established in our laboratory so far would indicate that generally, G3BP-2 is expressed in normal tissue and it expression changes in some cancers studied so far. Considering that G3BP-2 lies in a pathway known to be involved in cancer progression it is important to understand what effects the inappropriate expression of G3BP-2 may have on cancer progression and survival. This project is designed to characterise what signals the cell uses to control these proteins and in turn which genes these may effect. In this way we may be able to determine how external signals may effect tumour progression and on what genes this influence is expressed. It would be hoped that this project would increase our understanding of cancer and potentially lead to new diagnostic reagents and therapies in the treatment of cancer.Read moreRead less
Approaches to combat AIDS and its causative agent, the human immunodeficiency virus HIV-1, have thus far proved ineffective. The proposed research program intends to investigate the nuclear import of two HIV-1 proteins which have central roles in HIV infection. We will apply our expertise in the area of the regulation of nuclear import of viral proteins, and build on our observations with respect to these proteins to attempt to establish the mechanistic basis of their nuclear import, and how thi ....Approaches to combat AIDS and its causative agent, the human immunodeficiency virus HIV-1, have thus far proved ineffective. The proposed research program intends to investigate the nuclear import of two HIV-1 proteins which have central roles in HIV infection. We will apply our expertise in the area of the regulation of nuclear import of viral proteins, and build on our observations with respect to these proteins to attempt to establish the mechanistic basis of their nuclear import, and how this differs from the conventional nuclear import pathways used by normal cellular proteins. We already have evidence that nuclear import of HIV-Tat is regulated in novel fashion by cellular factors, and intend, through determining its mechanistic basis, to be able to form the basis of a strategy to block this import pathway specifically, and thereby inhibit HIV replication. This may form the basis in the future of a new pharmaceutical approach to combat HIV-AIDS.Read moreRead less