STUDIES OF NF-E4, A NOVEL FETAL/ERYTHROID SPECIFIC FACTOR INVOLVED IN FETAL GLOBIN GENE REGULATION
Funder
National Health and Medical Research Council
Funding Amount
$753,810.00
Summary
Sickle cell anemia and thalassemia are the commonest genetic disorders worldwide. Those affected suffer devastating clinical sequelae and mortality in the first twenty years of life remains high. A cure for these diseases is dependent on the replacement of the affected or absent hemoglobin protein chains with normally functioning hemoglobins. This is evident in rare patients who co-inherit a natural mutation which elevates fetal hemoglobin (HbF), as these patients have a dramatically ameliorated ....Sickle cell anemia and thalassemia are the commonest genetic disorders worldwide. Those affected suffer devastating clinical sequelae and mortality in the first twenty years of life remains high. A cure for these diseases is dependent on the replacement of the affected or absent hemoglobin protein chains with normally functioning hemoglobins. This is evident in rare patients who co-inherit a natural mutation which elevates fetal hemoglobin (HbF), as these patients have a dramatically ameliorated clinical course. Therefore, treatment strategies which could reactivate fetal globin gene expression after birth should be explored for these diseases. To achieve this goal we must further our understanding of the normal mechanisms of developmental regulation of globin gene expression. To this end we have recently identified a novel gene which is critical for fetal globin expression. The studies we propose here will further define the function of this gene and assess its potential for gene therapy for sickle cell disease and thalassemia.Read moreRead less
A Structural And Functional Basis For The Regulation Of Gene Expression By Nuclear Retention Of RNA
Funder
National Health and Medical Research Council
Funding Amount
$504,097.00
Summary
The nuclear retention mechanism is a novel way used by cells to control which genes are made into proteins - a fundamental process for all diseases, particularly cancers. This project will employ cutting edge structural and proteomic techniques to determine the molecular details underpinning nuclear retention. These insights will be important for the development of new tissue-restricted gene therapy applications and drugs targeting the cancers that rely on this mechanism.
Identifying Target Molecules Regulated By Nuclear Retention In Cancer And Development
Funder
National Health and Medical Research Council
Funding Amount
$267,173.00
Summary
Human DNA contains approximately 30000 genes; only twice as many as worms and flies, ten times as many as bacteria, and fewer than rice. Humans, however have considerably more complexity than these lower organisms. What are the factors responsible for the additional complexity? In the simplest scenario, one gene is transcribed to produce one message (mRNA), which is the blueprint for producing one protein. We now know that there are numerous mechanisms that potentially allow many different prote ....Human DNA contains approximately 30000 genes; only twice as many as worms and flies, ten times as many as bacteria, and fewer than rice. Humans, however have considerably more complexity than these lower organisms. What are the factors responsible for the additional complexity? In the simplest scenario, one gene is transcribed to produce one message (mRNA), which is the blueprint for producing one protein. We now know that there are numerous mechanisms that potentially allow many different proteins to be made from one gene. Also, it is the decisions about which gene will be made ( expressed ) into protein where and when in development, that is critical for our complexity. The control of gene expression is thus fundamental to all cellular processes and many diseases such as cancer and metabolic disorders are associated with some aspect of aberrant gene expression. The production of mRNA from DNA occurs in the human cell nucleus. The nucleus is not simply a bag of DNA, in fact, many important nuclear factors are organised into sub-nuclear bodies . Recently we discovered a novel sub-nuclear body, the paraspeckle and have been identifying its components and their function. Paraspeckles are involved in a previously undiscovered mechanism of the control of gene expression. Here, certain mRNA molecules are trapped in the nucleus until a signal is received from elsewhere in the cell, which causes the mRNA to be released and protein to be made. This Rapid Release Nuclear Retention mechanism effectively allows the quick production of specific proteins to be made on demand. In this project we propose to use cutting edge molecular and cell biology techniques to identify the special mRNA molecules that are trapped in paraspeckles in cancer cells. This will increase our understanding about the molecular details of this process, ultimately leading to potential uses in gene therapy, and should result in the discovery of important targets for cancer treatment.Read moreRead less
Variable Expressivity And Epigenetic Inheritance At The Axin Fused Locus In The Mouse
Funder
National Health and Medical Research Council
Funding Amount
$242,545.00
Summary
Genes influence the way we look and variations in gene sequence can account for the differences between individuals. Family traits are often credited to gene variants that are passed down through generations of families. There is now intriguing evidence, some coming from our laboratory, that gene sequence is not the only thing we inherit from our parents. Modifications that alter the expression but not the sequence of a gene, known as epigenetic modifications can, it turns out, be inherited in m ....Genes influence the way we look and variations in gene sequence can account for the differences between individuals. Family traits are often credited to gene variants that are passed down through generations of families. There is now intriguing evidence, some coming from our laboratory, that gene sequence is not the only thing we inherit from our parents. Modifications that alter the expression but not the sequence of a gene, known as epigenetic modifications can, it turns out, be inherited in mammals. An epigenetic modification is a mark, present on some genes that determines whether the gene is expressed (switched on) or silent. Animals are thought to acquire this mark during development and it is retained throughout life except in germ cells where the mark is generally, but not always, erased. The establishment of the mark appears to be a stochastic event at the cellular level resulting in mosaic expression. The percentage of marked cells can differ from one individual to another . In theory, this could help to explain why individuals with identical genetic information, such as identical twins, can have different phenotypic characteristics. The fact that these modifications can be inherited implies that there is an alternative mode of inheritance of genetic traits which does not involve mutation but which can be carried from generation to generation in a semipermanent way. Understanding the mechanisms underlying these events is important if we wish to predict or modify the phenotype of an invidual or that of his or her offspring.Read moreRead less
Identification Of Variably Expressed Genes In Isogenic Mice And Humans
Funder
National Health and Medical Research Council
Funding Amount
$293,080.00
Summary
Monozygotic twins are known to have different phenotypic characteristics even though they contain identical genetic information. It is not uncommon for identical twins to have different coloured eyes and to show discordance for genetic diseases. While there is no definitive explanation for these differences they are generally thought to be caused by subtle changes in environmental conditions. We believe however, that these differences are set up during early embryonic development by the establis ....Monozygotic twins are known to have different phenotypic characteristics even though they contain identical genetic information. It is not uncommon for identical twins to have different coloured eyes and to show discordance for genetic diseases. While there is no definitive explanation for these differences they are generally thought to be caused by subtle changes in environmental conditions. We believe however, that these differences are set up during early embryonic development by the establishment of epigenetic modifications to the DNA. An epigenetic modification is a mark which determines whether a gene is expressed (switched on) or silent (switched off). The establishment of the mark appears to be a stochastic event which can result in different physical characteristics between genetically identical individuals. We would like to study this process in inbred mouse strains and in humans. Inbred mouse strains are maintained by inbreeding (brother-sister mating) to ensure that all individuals of the strain are isogenic (genetically identical) and in such a way that environmental variation is minimised. We will use established molecular techniques to find genes which are variably expressed among isogenic mice and humans. This work will enable us to discover genes which are sensitive to epigenetic modifications and whose epigenotype must be known if we are able to predict phenotype or disease state.Read moreRead less
Epigenomic Marks As Indicators Of The Kinetics Of Gene Activation In Immune Cells.
Funder
National Health and Medical Research Council
Funding Amount
$619,805.00
Summary
Switching on an immune response involves major changes in the gene expression program of the immune cells. These changes in gene expression take place in the context of DNA packaged into the nucleus in a structure known as chromatin. We will investigate the relationship between chromatin and gene expression changes and how this relationship plays a role in the timing of the immune response. This information will be useful in developing novel means of controlling aberrant immune responses.
Functional Validation Of FoxP3 Target Genes In Human Regulatory T Cells
Funder
National Health and Medical Research Council
Funding Amount
$545,341.00
Summary
Using DNA based technologies we have focused on rare white blood cells known as regulatory T cells. These cells are policeman of the immune system and are responsible for maintaining balanced immune reactions, and preventing attack against harmless substances. These cells prevent autoimmune disease in healthy individuals, and only by first understanding how they work normally can we investigate and correct the defects in autoimmune diseases such as type 1 diabetes.
Investigation Into The Alternative Splicing Of Steroid Hormone Regulated Genes In Breast Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$292,216.00
Summary
Steroid hormones have imortant roles in breast tissue growth and differentiation. We have identified several proteins called PRMT6 and CAPER's , that are involved in steroid hormone signaling and control the alternative splicing of RNA, the process in which several different proteins can be produced from a single gene. Our aim is to study these proteins in an effort to understand how they influence alternative splicing and to identify genes they control in relation to breast cancer.
Regulation Of Expression Of The MicroRNA-200 Family
Funder
National Health and Medical Research Council
Funding Amount
$573,557.00
Summary
The majority of deaths from cancer are due to tumour metastasis. To metastasize, tumour cells must convert to a migratory form that can allow tumor cells to migrate and disseminate in the body. This process requires a genetic reprogramming of the cell. We have discovered that this genetic reprogramming is under the control of small RNA molecules called microRNAs. In this project we investigate what controls the levels of the microRNAs, to allow metastasis to occur in colon tumours.
The Establishment Of Epigenetic Marks At Metastable Epialleles In The Mouse
Funder
National Health and Medical Research Council
Funding Amount
$372,750.00
Summary
Occasionally, identical twins are found to have distinctly different characteristics, such as eye colour or severity of genetic disease, that clearly cannot be explained by their genetic makeup, and are unlikely to be the result of environmental differences. In genetically identical mice, similar cases exist, where some mice have a yellow coat and others a brown coat. In instances such as these, a growing body of evidence suggests that certain modifications to genes are responsible. These modifi ....Occasionally, identical twins are found to have distinctly different characteristics, such as eye colour or severity of genetic disease, that clearly cannot be explained by their genetic makeup, and are unlikely to be the result of environmental differences. In genetically identical mice, similar cases exist, where some mice have a yellow coat and others a brown coat. In instances such as these, a growing body of evidence suggests that certain modifications to genes are responsible. These modifications are not traditional DNA mutations, but are chemical modifications of the basic sequence. Currently, we do not know when these DNA modifications are established during foetal development. We will use the mouse coat colour gene mentioned above to investigate when the different physical characteristics are established in embryonic development. Indeed, there is increasing evidence that critical periods exist in human foetal development where minor environmental or nutritional changes can affect long-term health of the adult. Perhaps the establishment of the DNA modifications are under an environmental or nutritional influence. Further study of when and how the DNA modifications are set-up during embryonic development is necessary in order to understand these events.Read moreRead less