Impact Of The Extraembryonic Tissues On Early Embryonic Development: Genetic Basis Of Abnormal Body Plan
Funder
National Health and Medical Research Council
Funding Amount
$316,326.00
Summary
An important milestone of early development is the attachment (or implantation) of the embryo to the wall of the womb through the action of a specialized population of cells known as the trophoblasts. The early conceptus comprises not only cells that make up the embryo but also those (called extraembryonic cells) that later forms the placenta, and the membranes that wrap around the developing fetus. The placenta and the membranes are indispensable for the normal fetal growth by providing the eff ....An important milestone of early development is the attachment (or implantation) of the embryo to the wall of the womb through the action of a specialized population of cells known as the trophoblasts. The early conceptus comprises not only cells that make up the embryo but also those (called extraembryonic cells) that later forms the placenta, and the membranes that wrap around the developing fetus. The placenta and the membranes are indispensable for the normal fetal growth by providing the effective nourishment and protection for the developing fetus. Recent studies in the mouse have revealed that normal development of the recently implanted conceptus depends on the reciprocal interaction of the embryonic and extraembryonic cells. Abnormal embryo may form if the non-embryonic cells do not differentiate normally, as seen in the situation when an X-chromosome is lost from the female embryo (as in 45X0 Turner syndrome) and in early conceptus that carries a gene mutation that affects the production of growth factors by the extraembryonic cells. Functional deficiency of the extraembryonic cells might be a cause for early pregnancy loss where the conceptus has successfully implanted but the embryo fails to form. The remarkable conservation of the molecular mechanism that controls mammalian development allows us to use the mouse embryo as a genetic model for human development. The proposed project is designed to examine in a laboratory mouse model the molecular and cellular factors that regulate the activity of the extraembryonic cells. Specifically, we focus on a gene known as Sox17, which may be involved with the differentiation of the extraembryonic cells. We will study the impact of the mutation of this gene on the development of the early embryo to test the hypothesis that the extraembryonic cells may fulfill an important function in ensuring normal embryo formation, in addition to the other roles of nourishment and mechanical protection of the fetus.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
Multipotent Stem Cells Derived From Postimplantation Mouse Embryos: Evaluation Of Germ Layer Differentiation Potential
Funder
National Health and Medical Research Council
Funding Amount
$788,818.00
Summary
This study of the properties of cells that can differentiate into specific lineages provides useful insights into the cellular and molecular mechanisms for the specification of these progenitors from the pluripotent stem cells. The procurement of tissue-specific precursor cells that are capable of self-renewing and population expansion is a critical pre-requisite for achieving directed differentiation of stem cells into therapeutically useful cells for tissue replacement and regeneration.
Disorders of sexual development (DSDs) are surprisingly common, and often result in infertility, genital abnormalities, gender mis-assignment and long-term psychological trauma. In this Program we will pool our expertise in human molecular genetics, mouse developmental biology and protein chemistry to identify genes important for sex determination and development of the gonads, and discover how they contribute to DSD, in order to improve clinical care to patients with DSD.
Understanding And Preventing Adverse Developmental Effects Of Perinatal Infection/inflammation
Funder
National Health and Medical Research Council
Funding Amount
$621,458.00
Summary
Exposure of babies to infection or inflammation within the womb is common and is associated with preterm delivery and illness in newborns. The biggest problem for these babies is lung disease due to inflammation of the lungs before birth and/or in response to lung injury after birth. We are investigating how inflammation alters lung development, and working on developing a novel cell therapy to prevent life-threatening newborn lung disease.
Molecular Genetics Of Sex Determination And Gonad Development
Funder
National Health and Medical Research Council
Funding Amount
$4,580,898.00
Summary
Intersex disorders - ranging in severity from hypospadias (misplacement of the urethral opening) to complete sex reversal - are surprisingly common, with estimates as high as 4% of all live births. These disorders usually result in infertility, genital abnormalities, gender mis-assignment and long-term psychological trauma. 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 ....Intersex disorders - ranging in severity from hypospadias (misplacement of the urethral opening) to complete sex reversal - are surprisingly common, with estimates as high as 4% of all live births. These disorders usually result in infertility, genital abnormalities, gender mis-assignment and long-term psychological trauma. 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 program 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. Australia boasts three of the foremost international researchers in sex determination. Their contributions have been fundamental to the advancement of the field, including the identification and characterization of the master testis determining gene and other genes critical for sex determination. They now propose to pool their expertise in human molecular genetics, mouse developmental biology and protein chemistry to bring spectacular advances in our knowledge of human sexual development and its associated disorders. This information will be used to bring improved clinical care to patients withdisorders of sexual development.Read moreRead less
Modern Chemical Exposures In Utero And In Infancy, And Their Impact Upon Early Neurodevelopmental Outcomes In The Barwon Infant Study, An Unselected Birth Cohort Study
Funder
National Health and Medical Research Council
Funding Amount
$138,353.00
Summary
I am a paediatric doctor interested in the effects of modern industrial chemicals on children’s development. Even in the womb babies are exposed to industrial chemicals and we know some, like lead, are harmful to developing brains. I am interested in other chemicals that are now suspected to affect development, including the polybrominated diphenyl esters (PBDEs), and I intend to investigate this as part of the Barwon Infant Study, which follows 1250 children from before birth to 3 years.
Developing An In Vitro Model Of A Human Blastocyst
Funder
National Health and Medical Research Council
Funding Amount
$890,062.00
Summary
Using novel cellular and molecular technologies we propose to develop an artificial model of an early human blastocyst. This will allow us to study the first initial steps in human development without the use of real embryos. Such a model will not only help us decipher the first steps in human development, but we anticipate it will be essential to study how gene mutations and the environment affect this initial step in human development.
Characterisation Of Eurl, A Novel Gene Implicated In The Etiology Of Abnormal Brain Development And Intellectual Disability
Funder
National Health and Medical Research Council
Funding Amount
$597,541.00
Summary
Intellectual disability affects around one per cent of Australians, and can arise from genetic abnormalities during fetal life, such as through abnormal regulation of gene expression. We have identified a novel gene, known as eurl, which controls brain assembly as well as the ability of neurons to form functional connections within the brain. We will investigate how this novel gene controls brain development, and characterise eurl as a potential therapeutic target for learning and memory.
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