Cellular Mechanisms Underlying The Sense Of Balance
Funder
National Health and Medical Research Council
Funding Amount
$192,960.00
Summary
Dizziness, vertigo, and imbalance are major reasons for visits to the doctor, particularly by the elderly. For example, balance related falls account for an astonishing 50% of accidental deaths in people over 65. Inner ear disturbances account for 85% of these cases. Illness, infections, disease, head trauma or simply the natural aging process cause these disturbances and it is thought that they result in abnormal signals being sent from the inner ear to the brain. In spite of the health costs a ....Dizziness, vertigo, and imbalance are major reasons for visits to the doctor, particularly by the elderly. For example, balance related falls account for an astonishing 50% of accidental deaths in people over 65. Inner ear disturbances account for 85% of these cases. Illness, infections, disease, head trauma or simply the natural aging process cause these disturbances and it is thought that they result in abnormal signals being sent from the inner ear to the brain. In spite of the health costs associated with disorders of balance, very little is known about how signals are generated in our vestibular organs, let alone what abnormal changes may occur. Our attempts to understand balance in humans have been hampered by the lack of suitable experimental models. This proposal takes advantage of a newly developed mouse preparation to study key problems that could not be realistically addressed in whole animal or dissociated cells. We will investigate three critical components of balance organs. These components are: 1) hair cells that detect motion; 2) nerve endings that send information from hair cells to the brain; and 3) nerve endings that bring information from the brain. The aim of this proposal is to understand how these components interact with each other to provide us with a sense of balance. This knowledge will be the first of its kind and contribute significantly to our understanding of human vestibular function and pathology.Read moreRead less
Disorders of sexual development are among the most common form of birth defects in humans (1 in 4,000 births) because failure of the gonads to develop does not affect the viability of the individual. Such disorders can have profound psychological and medical consequences upon the individual, family, and society. Some intersexual conditions are the result of inappropriate exposure to hormones during fetal life, and others are due to spontaneous or inherited gene mutation. About 5-10% of ovarian c ....Disorders of sexual development are among the most common form of birth defects in humans (1 in 4,000 births) because failure of the gonads to develop does not affect the viability of the individual. Such disorders can have profound psychological and medical consequences upon the individual, family, and society. Some intersexual conditions are the result of inappropriate exposure to hormones during fetal life, and others are due to spontaneous or inherited gene mutation. About 5-10% of ovarian cancer cases, that affect 1 in 8000 Australian women, are due to the inheritance of a faulty gene. An understanding of the way gene expression and hence tissue differentiation is altered after sex reversal will inform us about the causes and consequences of normal and abnormal sexual development, gonadal malignancies and infertility. The gonad is unusual in that two completely different organs can arise from an essentially identical primordium, so that errors in development lead to intersexual phenotypes. We will use our new experimental animal model to clarify these processes.Read moreRead less
Dissecting The Role Of Hedgehog Signalling In Chondrogenesis And Skeletal Disease
Funder
National Health and Medical Research Council
Funding Amount
$408,739.00
Summary
There are close to 400 inherited disorders that affect how the skeleton develops, as well as a range of injury and age-related skeletal defects. There is much interest in treating such abnormalities with artificial bone grown outside the body. In order to achieve this aim we must understand all of the processes involved in producing and maintaining bone within the body. We are using both mouse and cell culture models of skeletal development to increase our understanding of these processes.
THE ROLE OF UBIQUITIN LIGASE ADAPTOR PROTEIN NDFIP1 IN NEURONAL DEVELOPMENT
Funder
National Health and Medical Research Council
Funding Amount
$581,813.00
Summary
Many brain diseases are characterized by faulty connections between nerve cells (neurons), in some cases caused by the inability to remove unwanted proteins from the neuron. This function is carried out by the ubiquitin-proteasome system (UPS). We have evidence that a UPS protein called Ndfip1 is important for forming functional brain circuits. We aim to discover whether neuron growth, branching and connectivity is promoted by Ndfip1 targeting of PTEN (phosphatase with tensin homology) to the UP ....Many brain diseases are characterized by faulty connections between nerve cells (neurons), in some cases caused by the inability to remove unwanted proteins from the neuron. This function is carried out by the ubiquitin-proteasome system (UPS). We have evidence that a UPS protein called Ndfip1 is important for forming functional brain circuits. We aim to discover whether neuron growth, branching and connectivity is promoted by Ndfip1 targeting of PTEN (phosphatase with tensin homology) to the UPS.Read moreRead less
Body Segment Identity Specification By The Transcription Regulator, Moz
Funder
National Health and Medical Research Council
Funding Amount
$366,301.00
Summary
One in 28 newborns have birth defects. Cleft palate and aortic arch defects are among the most common, always requiring surgery and often causing lethality. We propose to study a protein, Moz, which is essential for palate and aortic arch development. Moz (Monocytic leukaemia zinc finger protein) was first identified in human chromosomal abnormalities causing particularly aggressive forms of childhood and adult leukaemia. We have shown previously that Moz is essential for the formation of blood ....One in 28 newborns have birth defects. Cleft palate and aortic arch defects are among the most common, always requiring surgery and often causing lethality. We propose to study a protein, Moz, which is essential for palate and aortic arch development. Moz (Monocytic leukaemia zinc finger protein) was first identified in human chromosomal abnormalities causing particularly aggressive forms of childhood and adult leukaemia. We have shown previously that Moz is essential for the formation of blood stem cells. Moz can regulate the activity of genes, but which genes it regulates in vivo is unknown. In the absence of Moz, mice are born with a cleft palate, lack the thymus, where immune cells are instructed, and fail to form the lung blood circulation, so that they are unable to supply their blood with oxygen after birth. Moz deficiency also causes defects of the vertebrate column, such that individual vertebrae acquire the appearance of their neighbours. These symptoms are typical for a general defect in positional information of individual body segments with respect to their location along the body axis. We will investigate the molecular mechanisms that require Moz in patterning of the body axis. This project will characterize a genetic mechanism that is crucial for normal development of the palate, the aorta and the vertebrate column.Read moreRead less
Molecular Genetics Of Sex Determination And Gonad Development
Funder
National Health and Medical Research Council
Funding Amount
$539,000.00
Summary
Disorders of sexual development are among the most common forms of birth defects in humans (1 in 4,000 births). Many other childhood conditions with this incidence warrant prenatal diagnosis or neonatal screening. These disorders often result in infertility, genital abnormalities and gender mis-assignment. Uncertainty about a child s gender at birth can be very traumatic physically and psychologically for the individual and family concerned. There are profound consequences in later life for the ....Disorders of sexual development are among the most common forms of birth defects in humans (1 in 4,000 births). Many other childhood conditions with this incidence warrant prenatal diagnosis or neonatal screening. These disorders often result in infertility, genital abnormalities and gender mis-assignment. Uncertainty about a child s gender at birth can be very traumatic physically and psychologically for the individual and family concerned. There are profound consequences in later life for the affected individual. The cause of these problems is most often the failure of the delicate network of gene regulation that is responsible for proper development of testes or ovaries in the embryo. This research project will identify genes important for sex determination and development of the gonads, find out how these genes function and interact, and discover how they contribute to cases of aberrant sexual development in humans.Read moreRead less
The Role Of Scube Genes In Hedgehog Signal Transduction
Funder
National Health and Medical Research Council
Funding Amount
$496,446.00
Summary
Cancer often results form the miss-regulation and-or mutation of genes that control tissue formation in the developing embryo. Particular sets of genes combine to form a signal transduction pathway that coordinates the cell's response to its environment during the course of normal fetal growth. One such pathway is called the Hedgehog signal transduction pathway which has been shown to coordinated cell division and patterning within malignant and normal tissues. Genes encoding components of this ....Cancer often results form the miss-regulation and-or mutation of genes that control tissue formation in the developing embryo. Particular sets of genes combine to form a signal transduction pathway that coordinates the cell's response to its environment during the course of normal fetal growth. One such pathway is called the Hedgehog signal transduction pathway which has been shown to coordinated cell division and patterning within malignant and normal tissues. Genes encoding components of this pathway are mutated in the most common forms of human cancers. Understanding how this pathway is regulated is critical to designing strategies to treat the onset and progression of these cancers. The studies outlined in this grant plan to study a new component of this pathway that we have identified in our laboratory, in an easy to study vertebrate model, the zebrafish embryo. We plan to study how this class of proteins, termed scube proteins, acts to control activation of the pathway. We hope this will lead to a fuller understanding of this process, and at the same time help understand the nature of the end result of the patterning process within the muscle cells that we are studyingRead moreRead less
The Identification Of Genes Involved In Mammalian Craniofacial Development And Disease
Funder
National Health and Medical Research Council
Funding Amount
$408,055.00
Summary
Birth defects arising from abnormal development of the embryo are a major cause of infant mortality and childhood disabilities. On average 3-4% of liveborn babies have a major congenital abnormality, and of the 15-20% of pregnancies which spontaneously abort, many are due to chromosomal or other developmental anomalies. A common feature of many developmental disorders is dysmorphology of the face, suggesting that genes important in patterning the face are also important in the development of oth ....Birth defects arising from abnormal development of the embryo are a major cause of infant mortality and childhood disabilities. On average 3-4% of liveborn babies have a major congenital abnormality, and of the 15-20% of pregnancies which spontaneously abort, many are due to chromosomal or other developmental anomalies. A common feature of many developmental disorders is dysmorphology of the face, suggesting that genes important in patterning the face are also important in the development of other organ systems. During development of the embryo many of the features of the face derive from a series of swellings termed the pharyngeal arches. The complex processes which determine how the face develops are in a large part controlled by the co-ordinated expression of a large number of genes in the first two of the five pharyngeal arch pairs. While we know some of the genes involved in these processes, the precise mechanisms of craniofacial development are relatively poorly understood. In this project we propose a large scale approach to identifying genes involved in development of the mammalian face and to further delineating their role in development and human disease. This approach takes advantage of state of the art genomic technologies available at the IMB and through existing collaborations overseas. In collaboration with Dr Bento Soares (University of Iowa) we have constructed a library containing all of the genes which are expressed in the first two pairs of pharyngeal arches in the developing mouse embryo. Using an approach designed to eliminate all those genes which are expressed in all or most tissues of the body and play a general role in the body's metabolism, we will select for those genes which play a specific and important role in embryonic development. We will then isolate the human counterparts of these genes and more thoroughly investigate their role in embryonic development and disease.Read moreRead less