Functional Screening Of Novel Genes In Craniofacial Development
Funder
National Health and Medical Research Council
Funding Amount
$540,075.00
Summary
Our faces are central to our ability to communicate, feed, breath and interact with each other. Birth defects that impact on the normal development of the face are common and affect not only the child but have a dramatic impact on the child's family as well. The genetic causes of most facial birth defects are unknown. This project will develop a method for determining how development of the face is controlled and will help identify genes that are responsible for facial birth defects.
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.
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
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
The Role Of Ryk/AF6/Eph Complexes In Neuronal Pathfinding/fasciculation
Funder
National Health and Medical Research Council
Funding Amount
$422,036.00
Summary
During embryonic development nerve cells in the central nervous system have to find the right connections to make with other nerve cells. The process by which nerve cells find the right partners to make connections with is called neuronal pathfinding. Once some nerve cells have made the right connections, other nerve cells attach to these cells and form bundles of nerve fibres. This process is called fasciculation or bundling. This whole process is vital to the normal development and function of ....During embryonic development nerve cells in the central nervous system have to find the right connections to make with other nerve cells. The process by which nerve cells find the right partners to make connections with is called neuronal pathfinding. Once some nerve cells have made the right connections, other nerve cells attach to these cells and form bundles of nerve fibres. This process is called fasciculation or bundling. This whole process is vital to the normal development and function of the central nervous system and the brain. Without the right connections between nerves, information could not be received, processed or sent to organs in the body. We are now starting to discover some of the molecules which control the process of nerve cell pathfinding during development. It has been known for some time that proteins called Eph receptors play an important role in neuronal pathfinding and development of the head region in mice. We have now discovered that two other proteins called Ryk and AF-6 are able to bind to Eph receptors. We have very recently created mice which lack the Ryk protein and these mice have defects in their head deveopment strikingly similarto the head defects seen in mice that lack Eph receptors. We now wish to see whether Ryk mice have defects in neuronal pathfinding and fasciculation as do mice lacking Eph receptors. We also think that Ryk, Af-6 and Eph receptors form a protein complex which can modify cell function. We now wish to explore how this protein complex can do this.Read moreRead less
Hedgehog Signalling In Limb And Craniofacial Development And Disease
Funder
National Health and Medical Research Council
Funding Amount
$494,544.00
Summary
Anomalies of the face and limbs are amongst the most common features of human birth defects, and their frequent association suggests that the same genes are involved in governing the development of the limbs and face during embryogenesis. We have used a genomics-based approach to identify genes involved in limb development based on their alteration in a mouse model which develops extra fingers and toes. Defects in this mouse result from changes in Gli3, a gene which is known to be important in b ....Anomalies of the face and limbs are amongst the most common features of human birth defects, and their frequent association suggests that the same genes are involved in governing the development of the limbs and face during embryogenesis. We have used a genomics-based approach to identify genes involved in limb development based on their alteration in a mouse model which develops extra fingers and toes. Defects in this mouse result from changes in Gli3, a gene which is known to be important in both limb and face development. Based on the organs in which our genes of interest are active, we believe that they will also play key roles in embryonic development of the limbs, face and other organs. We now plan to investigate the regulation of a subset of these genes based on analysis in mouse models of limb and face development. In addition, we have chosen to further analyse the function of a completely novel gene we have identified which our preliminary studies suggest may play a role in the normal development of the lip and palate. These studies have the potential to shed light on the processes governing how organs develop, as well as on the molecular basis of common birth defects such as polydactyly (extra fingers and toes) and cleft palate.Read moreRead less
Head Development: Genetic Determinants And Tissue Potency
Funder
National Health and Medical Research Council
Funding Amount
$947,116.00
Summary
Congenital malformations involving major defects of brain (anencephalus and related anomalies) and facial structures (ear, face and neck) are encountered in 3.4 and 1.4 per 10000 births respectively (Congenital Malformations Australia 1981-1996, National Perinatal Statistics Unit) and they constitute a substantial clinical burden. It is believed that these major structural defects usually result from abnormal development in the first trimester, which coincides with the time frame for the formati ....Congenital malformations involving major defects of brain (anencephalus and related anomalies) and facial structures (ear, face and neck) are encountered in 3.4 and 1.4 per 10000 births respectively (Congenital Malformations Australia 1981-1996, National Perinatal Statistics Unit) and they constitute a substantial clinical burden. It is believed that these major structural defects usually result from abnormal development in the first trimester, which coincides with the time frame for the formation of the basic components of the embryonic head in the mouse. Knowledge of the formation of the head in the mouse model is therefore relevant to the understanding of related developmental processes in early human development. This project which involves the application of sophisticated embryological and molecular analyses on mouse embryos generated by transgenesis and genetic manipulation provides a detailed studies of craniofacial morphogenesis in a mammalian model for early human development. The micro-manipulation procedures, embryo culture, fluorescence microscopy and the in situ hybridization are routinely performed in our laboratory, and most of the mouse lines are well established in my laboratory. Experiments proposed for this project that focus on the embryological and molecular analysis of normal and mutant embryos should discover new information on the cellular and molecular mechanisms that regulate head development. The knowledge will also offer insight into the pathogenesis of similar craniofacial malformations in other mutant embryos.Read moreRead less
Genetic Control Of Body Patterning: Intersection Of Transcriptional And Signalling Activity In Head Formation
Funder
National Health and Medical Research Council
Funding Amount
$579,932.00
Summary
A most critical step in embryonic development is the assembly of the different tissue components into a three-dimensional structure in order to build a major body part of the foetus. The objective of our research is to understand how the mechanisms that control genetic activity and cell-to-cell signalling may cooperate in the formation of the head and face of the embryo. The outcome will focus future clinical investigations to the most relevant genetic determinants of craniofacial defects.
Normal embryonic and foetal devlopment depends on the ability of cells to move from one place to another. This behaviour enables cells to be produced at one site and transported to one or a number of other sites. Although the face appears to us as a single seamless unit it originates as a number of blocks of tissue which begin development separately and must grow in a coordinated way that enables them to meet at precisely the correct time, in the correct place and in the correct order. The basis ....Normal embryonic and foetal devlopment depends on the ability of cells to move from one place to another. This behaviour enables cells to be produced at one site and transported to one or a number of other sites. Although the face appears to us as a single seamless unit it originates as a number of blocks of tissue which begin development separately and must grow in a coordinated way that enables them to meet at precisely the correct time, in the correct place and in the correct order. The basis of this growth and fusion is the ability of individual cells to move around the embryo to supply the raw materials for this construction process when and where they are needed. The combined activities of the cells in constructing the various parts of the embryo is known as morphogenesis which literally means creating shape. We are trying to gain insight into the basis of morphogenesis that produces the face. This is important because the face and other structures that are closely associated with it are particularly prone to errors. Despite this, surprisingly little is known about the mechansims that control development of the face. We know a great deal about which cells are involved in constructing the face but very little about what triggers the initial steps of development or maintains ordered growth. Our research is aimed at defining genes that are important in controlling development of the face through the study of normal development and birth defects. We are defining the function of genes that appear to be important in controlling the behaviour of cells during early development of the face. This knowledge will assist in understanding the control mechanism for facial devlopment and will eventually lead to improvements in the treatment and prevention of birth defects affecting these structures.Read moreRead less
THE ROLE OF NOVEL TUMOUR SUPPRESSORS DURING DEVELOPMENT
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
Cancer is a disease that is likely to affect 1-4 people at some point in their lifetime. Therefore, understanding what causes cancer is of major importance to medical science. Cancers arise through the accumulation of mutations that alter normal cell proliferation control, differentiation or apoptosis (programed cell death). Many genes involved in cancer have been identified, however, there are likely to be many more genes, that when disrupted or misexpressed can lead to cancer. We are intereste ....Cancer is a disease that is likely to affect 1-4 people at some point in their lifetime. Therefore, understanding what causes cancer is of major importance to medical science. Cancers arise through the accumulation of mutations that alter normal cell proliferation control, differentiation or apoptosis (programed cell death). Many genes involved in cancer have been identified, however, there are likely to be many more genes, that when disrupted or misexpressed can lead to cancer. We are interested in the regulation of cell proliferation, and have been studying this in the genetically amenable animal model system, Drosophila. Central to the control of cell proliferation in all organisms are the Cyclin dependent protein kinases. Cyclin E-dependent protein kinase is required to drive cells from the G1 (resting state) into S phase (where DNA replication occurs). Correct control of Cyclin E is important in limiting cell proliferation and many cancer causing mutations result in up-regulation of this critical cell cycle regulator and premature entry into the cell cycle. We have used a genetic approach using a weak mutation in Drosophila Cyclin E to isolate mutations in other important regulators of the G1 to S phase transition. We have identified a number of genes that act to negatively regulate the cell cycle, 2 of which have characteristics typical of tumour suppressors. We have identified candidate genes for 3 of these mutations, all of which encode novel proteins related to mammalian proteins involved in negative regulation of cell proliferation or tumour suppressors. In this proposal we seek to determine the way in which these proteins function to control cell proliferation in Drosophila. Due to the remarkable conservation of genes involved in cell proliferation control through evolution, this study is likely to be highly relevant to the control of cell proliferation and the development of cancer in humans.Read moreRead less