How Does Basal Chromatic Structure Predict Cytokine Gene Responses?
Funder
National Health and Medical Research Council
Funding Amount
$521,961.00
Summary
To recognise foreign pathogens and eradicate them from the body, immune cells need to quickly switch on genes encoding factors which communicate between cells and drive the immune response. Incorrect expression of these genes contributes to immune diseases such as asthma, arthritis and leukaemia. The aim of this project is to study how the DNA environment of immune genes controls their ability to be switched on and off, and how altering this environment leads to incorrect gene expression.
Epigenetic modifications to the genome do not involve DNA sequence changes but modify gene expression during normal development. In diseases, like cancer, epigenetic modifications modulate gene expression in favour of disease progression. We will study the SmcHD1 gene that is involved in X chromosome inactivation, an epigenetic mechanism operating to ensure equal dosage of X-linked genes between males and females. This project will aid our understanding of chromosome structure and function.
The Role Of The MYST Family Transcriptional Co-activator, Mof, In Embryonic Development
Funder
National Health and Medical Research Council
Funding Amount
$319,446.00
Summary
A major task in biology is to understand how the human genome directs the development of a single cell to form an entire individual. Clearly, a large part of this task is to understand how the expression of genes is regulated during embryonic development. Gene expression requires co-activator complexes. Co-activator complexes typically contain proteins which regulate the structure of chromatin (a complex of DNA and histones). However, the physiological function of most co-activators is entirely ....A major task in biology is to understand how the human genome directs the development of a single cell to form an entire individual. Clearly, a large part of this task is to understand how the expression of genes is regulated during embryonic development. Gene expression requires co-activator complexes. Co-activator complexes typically contain proteins which regulate the structure of chromatin (a complex of DNA and histones). However, the physiological function of most co-activators is entirely unclear. The aim of this project is to study the function of Mof during embryonic development. Mof is a co-activator that directly regulates chromatin structure by modifying histones. Mof is a member of the MYST family of co activators, which includes Moz and Qkf. We have recently shown that Moz and Qkf are essential for the haematopoietic stem cell population and the neural stem cell population, respectively. The purpose of this project is to produce a detailed analysis of the function of Mof in vivo and determine it's importance in regulating gene expression. All biological processes relay on accurate regulation of gene transcription and all diseases, whether they involve pathogens or cell intrinsic pathological changes, such as cancer, lead to changes in gene expression. Regulation of chromatin structure has been identified as a major mechanism of transcriptional regulation in health and disease. However, our understanding of the precise molecular mechanisms regulating chromatin structure in vivo are very limited. This work will fully investigate the role of an important co-activator in vivo including a mechanistic analysis. This will increase understanding of how gene expression is regulated and, ultimately, this knowledge will find wide application in the development of new treatment paradigms.Read moreRead less
The Role Of The MYST Family Lysine Acetyltransferase, Hbo1, In Development And In The Adult
Funder
National Health and Medical Research Council
Funding Amount
$403,368.00
Summary
This project will produce a detailed analysis of the function of Hbo1, a transcription factor, and determine its importance in regulating gene expression. All biological processes rely on accurate regulation of gene transcription and all diseases lead to changes in gene expression. This work will increase understanding of how gene expression is regulated and, ultimately, this knowledge will find wide application in the development of new treatment paradigms.
Mechanisms By Which Chromatin Modulates Gene Expression.
Funder
National Health and Medical Research Council
Funding Amount
$267,750.00
Summary
Gene expression in a cell occurs in the nucleus where genes are stored. In the nucleus, DNA is not in a free form but is covered with an equivalent weight of protein to form a structure known as chromatin. Chromatin is a periodic structure made up of repeating, regularly spaced subunits, the subunit being the nucleosome. A nucleosome consists of a group of proteins (histones) wrapped around with DNA. A nucleosome is both capable of blocking and activating gene expression. Therefore one important ....Gene expression in a cell occurs in the nucleus where genes are stored. In the nucleus, DNA is not in a free form but is covered with an equivalent weight of protein to form a structure known as chromatin. Chromatin is a periodic structure made up of repeating, regularly spaced subunits, the subunit being the nucleosome. A nucleosome consists of a group of proteins (histones) wrapped around with DNA. A nucleosome is both capable of blocking and activating gene expression. Therefore one important function of chromatin is to tightly regulate gene expression which is essential to allow an organism to develop properly. When gene expression is not accurately controlled by chromatin developmental defects or cancer can result from the production of incorrect proteins. To control correct gene expression, highly specific mechanisms must operate in the cell to remove, or modify, nucleosomes at certain genes at a precise time during development. One mechanism that we believe to be important is changing the make-up of a nucleosome. This can be achieved in the cell by the replacement of histones with different specialized forms of these histones (variants). We believe that these histone variants can specifically generate chromosomal domains which could in some cases expose or in other cases hide certain genes and thereby turn them on or off. Employing a new approach, we will study one of these histone variants to discover the role it plays in determining the type of chromosomal domain made and the role of this domain has in turning genes on or off at precise times in early development during the formation of different specialized cell types. This new information may define targets for the prevention of incorrect gene expression during cancer progression or abnormal development.Read moreRead less
The Organisation Of The Chromosome Into Distinct Epigenetic Domains And Its Link With Development And Disease
Funder
National Health and Medical Research Council
Funding Amount
$521,591.00
Summary
This investigation will show that a key cellular mechanism that determines how the chromosome is organised into stable domains is by changing the make-up of chromosomal domains through the replacement of histone proteins with specialised forms of histones called variants . This fundamental research will provide important new information on how chromosomes become unstable in cancer.
The Role Of The Transcriptional Co-activator, Qkf, In Adult Neural Stem Cell Self-renewal And Multi-potency.
Funder
National Health and Medical Research Council
Funding Amount
$403,709.00
Summary
In recent years there has been considerable interest in stem cells because they have the potential to provide new therapeutic approaches to disease. Indeed, haematopoietic stem cells are already used in treatments for leukaemia. Many organs in adult humans contain stem cells, including the brain. In order to develop safe, and effective, stem cell-based treatments for human diseases it is necessary to determine how proliferation and differentiation are regulated in adult stem cells.
One of the most amazing engineering achievements in nature is how over 2 meters of genetic material (DNA) can be compacted and squeezed nearly a million times to fit into a human cell. The remarkable structure that achieves this is the chromosome. Fundamental to the survival of a multicellular organism is that the chromosome is stably maintained throughout out the life of an organism. For example, defects in maintaining chromosome stability can lead to aneuploidy (cells with an abnormal number o ....One of the most amazing engineering achievements in nature is how over 2 meters of genetic material (DNA) can be compacted and squeezed nearly a million times to fit into a human cell. The remarkable structure that achieves this is the chromosome. Fundamental to the survival of a multicellular organism is that the chromosome is stably maintained throughout out the life of an organism. For example, defects in maintaining chromosome stability can lead to aneuploidy (cells with an abnormal number of chromosomes), a feature exhibited by many forms of cancer. This packaging of genomic DNA that produces a chromosome is achieved by a complex scheme of folding. At the first level, DNA is first wrapped around a mixture of proteins (called histones) to form a complete unit known as a nucleosome. About 30 million of these building blocks are required in every human cell to compact our DNA. Higher, more complicated levels of organization exist in which a linear array of nucleosomes fold to various extents to form distinct functional and structural domains. Importantly, specialised chromosomal domains, like the telomere and centromere, are assembled that keep the ends of the chromosomes stable and enable a chromosome to copy itself every time our cells divide and grow, respectively. How a chromosome is divided into these different compartments remains a mystery. This investigation will show that a key cellular mechanism that determines how the chromosome is organised into stable domains is by changing the make-up of chromosomal domains through the replacement of histone proteins with specialised forms of histones called variants . These histone variants control the way a linear array of nucleosomes fold into complex three-dimensional structures to perform a specialised function. This fundamental research will provide important new information on how chromosomes become unstable in cancer. It will also enable new strategies, which stabilise the chromosome, to be explored.Read moreRead less
Transcription At The Centromere: Roles In Formation, Maintenance And Function
Funder
National Health and Medical Research Council
Funding Amount
$549,092.00
Summary
Every human has 46 chromosomes. Chromosomes are structures that carry genes in all our cells. The centromere is an essential component of a chromosome which governs the process of cell division and separation of replicated chromosomes. Defects in centromere function cause abnormalities in cell division that in turn cause a variety of genetic diseases including cancer. We propose to investigate the role that transcription at the centromere plays in determining correct centromere function.